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Butorphanol: Drug information

Butorphanol: Drug information
(For additional information see "Butorphanol: Patient drug information")

For abbreviations, symbols, and age group definitions used in Lexicomp (show table)
ALERT: US Boxed Warning
Addiction, abuse, and misuse:

Butorphanol exposes patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death. Assess each patient’s risk prior to prescribing butorphanol, and monitor all patients regularly for the development of these behaviors or conditions.

Opioid analgesic risk evaluation and mitigation strategy (REMS):

To ensure that the benefits of opioid analgesics outweigh the risks of addiction, abuse, and misuse, the Food and Drug Administration (FDA) has required a REMS for these products. Under the requirements of the REMS, drug companies with approved opioid analgesic products must make REMS-compliant education programs available to health care providers. Health care providers are strongly encouraged to complete a REMS-compliant education program; counsel patients and/or their caregivers, with every prescription, on safe use, serious risks, storage, and disposal of these products; emphasize to patients and their caregivers the importance of reading the Medication Guide every time it is provided by their pharmacist; and consider other tools to improve patient, household, and community safety.

Life-threatening respiratory depression:

Serious, life-threatening, or fatal respiratory depression may occur with use of butorphanol. Monitor for respiratory depression, especially during initiation of butorphanol or following a dose increase.

Accidental exposure (intranasal):

Accidental exposure of even one dose of butorphanol, especially by children, can result in a fatal overdose of butorphanol.

Neonatal opioid withdrawal syndrome:

Prolonged use of butorphanol during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated, and requires management according to protocols developed by neonatology experts. If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available.

Cytochrome P450 3A4 interaction (intranasal):

The concomitant use of butorphanol with all cytochrome P450 3A4 inhibitors may result in an increase in butorphanol plasma concentrations, which could increase or prolong adverse reactions and may cause potentially fatal respiratory depression. In addition, discontinuation of a concomitantly used cytochrome P450 3A4 inducer may result in an increase in butorphanol plasma concentration. Monitor patients receiving butorphanol and any CYP3A4 inhibitor or inducer.

Risk from concomitant use with benzodiazepines or other CNS depressants (intranasal):

Concomitant use of opioids with benzodiazepines or other CNS depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of butorphanol and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required. Follow patients for signs and symptoms of respiratory depression and sedation.

Pharmacologic Category
  • Analgesic, Opioid;
  • Analgesic, Opioid Partial Agonist
Dosing: Adult

Note : When used for managing moderate to severe pain, opioids may be part of a comprehensive, multimodal, patient-specific treatment plan for pain. Maximize nonopioid analgesia, if appropriate, prior to initiation of opioid analgesia. Reserve butorphanol for patients for whom alternative treatment options (eg, nonopioid analgesics, opioid combination products) are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain. Butorphanol has an analgesic ceiling (CDC [Dowell 2016]; Hill 2018; Hoskin 1991; manufacturer's labeling). Dose selection: Dosing provided is based on typical doses and some patients may require higher or lower doses. Individualize dosing and dosing intervals based on patient-specific factors (eg, comorbidities, severity of pain, concomitant medications, cachexia, general condition, degree of opioid experience/tolerance) and titrate to patient-specific treatment goals (eg, improvement in function and quality of life, decrease in pain using a validated pain rating scale). Use the lowest effective dose for the shortest period of time. Safety: Consider prescribing naloxone for patients with factors associated with an increased risk for overdose, such as history of overdose or substance use disorder, higher opioid dosages, and/or concomitant benzodiazepine use (APS [Chou 2016]; CDC [Dowell 2016]; manufacturer's labeling).

Acute pain

Acute pain (alternative agent):

IM: Initial: 2 mg in patients who will be able to remain recumbent (in the event drowsiness or dizziness occurs); may repeat every 3 to 4 hours as needed; usual range: 1 to 4 mg every 3 to 4 hours as needed.

IV: Initial: 1 mg; may repeat every 3 to 4 hours as needed; usual range: 0.5 to 2 mg every 3 to 4 hours as needed.

Intranasal (spray): Initial: One spray (1 mg per spray) in 1 nostril; if adequate pain relief is not achieved within 60 to 90 minutes, an additional 1 spray in 1 nostril may be given; may repeat initial dose sequence in 3 to 4 hours after the last dose as needed.

Alternatively (depending on severity of pain), an initial dose of 2 mg (1 spray in each nostril) may be used in patients who will be able to remain recumbent (in the event drowsiness or dizziness occurs); additional doses should not be repeated for at least 3 to 4 hours after the initial dose.

Discontinuation of therapy: When discontinuing or tapering long-term opioid therapy, the dose should be gradually tapered. An optimal universal tapering schedule for all patients has not been established (CDC [Dowell 2016]). Proposed schedules range from slow (eg, 10% reductions per week) to rapid (eg, 25% to 50% reduction every few days) (CDC 2015). Individualize dosing based on discussions with patient to minimize opioid withdrawal while considering patient-specific goals and concerns as well as the opioid's pharmacokinetics. Slower tapers may be appropriate after long-term use (eg, years), particularly in the final stage of tapering, whereas more rapid tapers may be appropriate in patients experiencing severe adverse events (CDC [Dowell 2016]). During tapering, patients may be at an increased risk of overdose if they return to their original (or higher) opioid dose or use illicit opioids, due to rapid loss of tolerance; consider prescribing naloxone (HHS 2019). Monitor carefully for signs/symptoms of withdrawal. If the patient displays withdrawal symptoms, consider slowing the taper schedule; alterations may include increasing the interval between dose reductions, decreasing amount of daily dose reduction, pausing the taper and restarting when the patient is ready, and/or coadministration of an alpha-2 agonist (eg, clonidine) to blunt withdrawal symptoms (Berna 2015; CDC [Dowell 2016]). Continue to offer nonopioid analgesics as needed for pain management during the taper; consider nonopioid adjunctive treatments for withdrawal symptoms (eg, GI complaints, muscle spasm) as needed (Berna 2015; Sevarino 2022).

Pain during labor

Pain during labor (fetus ≥37 weeks' gestation and no signs of fetal distress):

Note: Alternative analgesia should be used for pain associated with delivery or if delivery is anticipated within 4 hours.

IM, IV: 1 to 2 mg; may repeat in 4 hours.

Preoperative sedation

Preoperative sedation:

IV: 2 mg once; administer shortly before induction.

IM: 2 mg once; administer 60 to 90 minutes before surgery.

Supplement to balanced anesthesia

Supplement to balanced anesthesia: IV: 2 mg shortly before induction; may be followed by incremental doses of 0.5 to 1 mg as needed during anesthesia (incremental dose dependent on previously administered sedative, analgesic, and hypnotic medications); usual total dose: 4 to 12.5 mg.

Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.

Dosing: Kidney Impairment: Adult

Acute pain (including pain during labor [fetus ≥37 weeks' gestation and no signs of fetal distress]) (alternative agent) :

IM: Initial: 1 mg; repeated dosing must be based on initial response rather than fixed intervals, but generally at least 6 hours from previous dose.

IV: Initial: 0.5 mg; repeated dosing must be based on initial response rather than fixed intervals, but generally at least 6 hours from previous dose.

Intranasal (spray): Initial: One spray (1 mg per spray) in 1 nostril; if adequate pain relief is not achieved within 90 to 120 minutes, an additional 1 spray in 1 nostril may be given. May repeat initial dose sequence as needed at intervals determined by patient response; usual interval: ≥6 hours between dosing sequences.

Preoperative sedation and supplement to balanced anesthesia: There are no dosage adjustments provided in the manufacturer's labeling.

Dosing: Hepatic Impairment: Adult

Acute pain (including pain during labor [fetus ≥37 weeks' gestation and no signs of fetal distress]) (alternative agent) :

IM: Initial: 1 mg; repeated dosing must be based on initial response rather than fixed intervals, but generally at least 6 hours from previous dose.

IV: Initial: 0.5 mg; repeated dosing must be based on initial response rather than fixed intervals, but generally at least 6 hours from previous dose.

Intranasal (spray): Initial: One spray (1 mg per spray) in 1 nostril; if adequate pain relief is not achieved within 90 to 120 minutes, an additional 1 spray in 1 nostril may be given. May repeat initial dose sequence as needed at intervals determined by patient response; usual interval: ≥6 hours between dosing sequences.

Preoperative sedation and supplement to balanced anesthesia: There are no dosage adjustments provided in the manufacturer's labeling.

Dosing: Older Adult

Acute pain (alternative agent):

IM: Initial: 1 mg; repeated dosing must be based on initial response rather than fixed intervals, but generally at least 6 hours from previous dose.

IV: Initial: 0.5 mg; repeated dosing must be based on initial response rather than fixed intervals, but generally at least 6 hours from previous dose.

Intranasal (spray): Initial: One spray (1 mg per spray) in 1 nostril; if adequate pain relief is not achieved within 90 to 120 minutes, an additional 1 spray in 1 nostril may be given. May repeat initial dose sequence as needed at intervals determined by patient response; usual interval: ≥6 hours between dosing sequences.

Refer to adult dosing for additional uses.

Dosage Forms: US

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution, Injection, as tartrate:

Generic: 2 mg/mL (1 mL, 2 mL)

Solution, Injection, as tartrate [preservative free]:

Generic: 1 mg/mL (1 mL)

Solution, Nasal, as tartrate:

Generic: 10 mg/mL (2.5 mL)

Generic Equivalent Available: US

Yes

Dosage Forms: Canada

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution, Nasal, as tartrate:

Generic: 10 mg/mL (2.5 mL)

Controlled Substance

C-IV

Administration: Adult

IV: Administer IV.

IM: Administer IM.

Intranasal: Fully prime pump prior to initial use; if not used for ≥48 hours, re-prime with one or two strokes. Aim spray away from self and others when priming.

Use: Labeled Indications

Acute pain: Management of pain severe enough to require an opioid analgesic and for which alternative treatments are inadequate.

Limitations of use: Reserve for use in patients for whom alternative treatment options (eg, nonopioid analgesics, opioid combination products) are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain.

Pain during labor (fetus ≥37 weeks' gestation and no signs of fetal distress) (injection only): Management of pain during labor.

Preoperative sedation (injection only): Preoperative or preanesthetic medication.

Supplement to balanced anesthesia (injection only): Supplement to balanced anesthesia.

Medication Safety Issues
Sound-alike/look-alike issues:

Stadol may be confused with Haldol, sotalol

High alert medication:

The Institute for Safe Medication Practices (ISMP) includes this medication among its list of drug classes which have a heightened risk of causing significant patient harm when used in error.

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.

>10%:

Central nervous system: Drowsiness (43%), dizziness (19%), insomnia (nasal spray 11%)

Gastrointestinal: Nausea and vomiting (13%)

Respiratory: Nasal congestion (nasal spray 13%)

1% to 10%:

Cardiovascular: Palpitations, vasodilation

Central nervous system: Anxiety, burning sensation, confusion, euphoria, floating feeling, headache, lethargy, nervousness, paresthesia

Dermatologic: Cold and clammy skin, diaphoresis, pruritus

Gastrointestinal: Anorexia, constipation, stomach pain, unpleasant taste, xerostomia

Neuromuscular & skeletal: Tremor, weakness

Ophthalmic: Blurred vision

Otic: Otalgia, tinnitus

Respiratory: Bronchitis, cough, dyspnea, epistaxis, nasal discomfort, pharyngitis, rhinitis, sinus congestion, sinusitis, upper respiratory tract infection

<1%, postmarketing, and/or case reports: Abnormal dreams, agitation, apnea, chest pain, convulsions, delusions, depression, drug dependence, dysphoria, edema, hallucination, hostility, hypertension, hypogonadism (Brennan, 2013; Debono, 2011), hypotension, respiratory depression, seizure, shallow respiration, skin rash, speech disturbance, syncope, tachycardia, urination disorder, urticaria, vertigo, withdrawal syndrome

Contraindications

Hypersensitivity (eg, anaphylaxis) to butorphanol or any component of the formulation; acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment; significant respiratory depression; GI obstruction, including paralytic ileus (known or suspected).

Canadian labeling: Additional contraindications for nasal spray (not in the US labeling): Suspected surgical abdomen (eg, acute appendicitis or pancreatitis); any disease/condition that affects bowel transit (eg, ileus of any type); mild pain manageable with other pain medications; chronic obstructive airway; status asthmaticus; hypercapnia and cor pulmonale; acute alcoholism; delirium tremors; seizure disorder; severe CNS depression; increased cerebrospinal or intracranial pressure; head injury; concomitant use with or within 14 days following monoamine oxidase inhibitor therapy; breastfeeding; pregnancy; use during labor and delivery.

Documentation of allergenic cross-reactivity for opioids is limited. However, because of similarities in chemical structure and/or pharmacologic actions, the possibility of cross-sensitivity cannot be ruled out with certainty.

Warnings/Precautions

Concerns related to adverse effects:

• CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving).

• Hypotension: May cause severe hypotension (including orthostatic hypotension and syncope); use with caution in patients with hypovolemia, cardiovascular disease (including acute myocardial infarction [MI]), or drugs which may exaggerate hypotensive effects (including phenothiazines or general anesthetics). Monitor for symptoms of hypotension following initiation or dose titration. Use with caution in patients with circulatory shock.

• Phenanthrene hypersensitivity: Use with caution in patients with hypersensitivity reactions to other phenanthrene-derivative opioid agonists (eg, codeine, hydromorphone, levorphanol, oxycodone, oxymorphone).

• Respiratory depression: Serious, life-threatening, or fatal respiratory depression may occur. Carbon dioxide retention from opioid-induced respiratory depression can exacerbate the sedating effects of opioids. Patients and caregivers should be educated on how to recognize respiratory depression and the importance of getting emergency assistance immediately (eg, calling 911) in the event of known or suspected overdose.

Disease-related concerns:

• Abdominal conditions: May obscure diagnosis or clinical course of patients with acute abdominal conditions.

• Adrenocortical insufficiency: Use with caution in patients with adrenal insufficiency, including Addison disease. Long-term opioid use may cause secondary hypogonadism, which may lead to mood disorders and osteoporosis (Brennan 2013).

• Biliary tract impairment: Use with caution in patients with biliary tract dysfunction, including acute pancreatitis; may cause constriction of sphincter of Oddi.

• Cardiovascular disease: Use extreme caution in patients with acute myocardial infarction, ventricular dysfunction, or coronary insufficiency; limit use to situations where the benefits clearly outweigh the risk.

• CNS depression/coma: Avoid use in patients with impaired consciousness or coma as these patients are susceptible to intracranial effects of CO2 retention.

• Delirium tremens: Use with caution in patients with delirium tremens.

• Head trauma: Use with extreme caution in patients with head injury, intracranial lesions, or elevated intracranial pressure (ICP); exaggerated elevation of ICP may occur.

• Hepatic impairment: Use with caution in patients with hepatic impairment. Dosage adjustments are recommended.

• Mental health conditions: Use opioids with caution for chronic pain in patients with mental health conditions (eg, depression, anxiety disorders, post-traumatic stress disorder) due to increased risk for opioid use disorder and overdose; more frequent monitoring is recommended (CDC [Dowell 2016]).

• Obesity: Use with caution in patients who are morbidly obese.

• Prostatic hyperplasia/urinary stricture: Use with caution in patients with prostatic hyperplasia and/or urinary stricture.

• Psychosis: Use with caution in patients with toxic psychosis.

• Renal impairment: Use with caution in patients with renal impairment. Dosage adjustments are recommended.

• Respiratory disease: Use with caution and monitor for respiratory depression in patients with significant chronic obstructive pulmonary disease or cor pulmonale, and those with a substantially decreased respiratory reserve, hypoxia, hypercapnia, or preexisting respiratory depression, particularly when initiating and titrating therapy; critical respiratory depression may occur, even at therapeutic dosages. Consider the use of alternative nonopioid analgesics in these patients.

• Seizures: Use with caution in patients with a history of seizure disorders; may cause or exacerbate preexisting seizures.

• Serotonin syndrome: Potentially life-threatening serotonin syndrome (SS) has occurred with concomitant use of butorphanol and serotonergic agents (eg, selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, buspirone, St John's wort, tryptophan) or agents that impair metabolism of serotonin (eg, monoamine oxidase [MAO] inhibitors intended to treat psychiatric disorders, other MAO inhibitors [ie, linezolid and intravenous methylene blue]). Monitor patients closely for signs of SS such as mental status changes (eg, agitation, hallucinations, delirium, coma); autonomic instability (eg, tachycardia, labile blood pressure, diaphoresis); neuromuscular changes (eg, tremor, rigidity, myoclonus); GI symptoms (eg, nausea, vomiting, diarrhea); and/or seizures.

• Sleep-related disorders: Opioid use increases the risk for sleep-related disorders (eg, central sleep apnea [CSA], hypoxemia) in a dose-dependent fashion. Use with caution for chronic pain and titrate dosage cautiously in patients with risk factors for sleep-disordered breathing (eg, heart failure, obesity). Consider dose reduction in patients presenting with CSA. Avoid opioids in patients with moderate to severe sleep-disordered breathing (CDC [Dowell 2016]).

• Thyroid dysfunction: Use with caution in patients with thyroid dysfunction.

Concurrent drug therapy issues:

• Benzodiazepines or other CNS depressants (intranasal): Concomitant use of opioids with benzodiazepines or other CNS depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Consider prescribing naloxone for emergency treatment of opioid overdose in patients taking benzodiazepines or other CNS depressants concomitantly with opioids.

Special populations:

• Cachectic or debilitated patients: Use with caution in cachectic or debilitated patients; there is a greater potential for critical respiratory depression, even at therapeutic dosages. Consider the use of alternative nonopioid analgesics in these patients.

• Older adults: Use with caution in older adults; may be more sensitive to adverse effects. Decrease initial dose. Use opioids for chronic pain with caution in this age group; monitor closely due to an increased potential for risks, including certain risks such as falls/fracture, cognitive impairment, and constipation. Clearance may also be reduced in older adults (with or without renal impairment) resulting in a narrow therapeutic window and increasing the risk for respiratory depression or overdose (CDC [Dowell 2016]). Consider the use of alternative nonopioid analgesics in these patients.

• Neonates: Neonatal opioid withdrawal syndrome: Prolonged use of opioids during pregnancy can cause neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated according to protocols developed by neonatology experts. Signs and symptoms include irritability, hyperactivity and abnormal sleep pattern, high-pitched cry, tremor, vomiting, diarrhea, and failure to gain weight. Onset, duration, and severity depend on the drug used, duration of use, maternal dose, and rate of drug elimination by the newborn.

Other warnings/precaution:

• Abrupt discontinuation/withdrawal: Abrupt discontinuation in patients who are physically dependent to opioids has been associated with serious withdrawal symptoms, uncontrolled pain, attempts to find other opioids (including illicit), and suicide. Use a collaborative, patient-specific taper schedule that minimizes the risk of withdrawal, considering factors such as current opioid dose, duration of use, type of pain, and physical and psychological factors. Monitor pain control, withdrawal symptoms, mood changes, suicidal ideation, and for use of other substances and provide care as needed. Concurrent use of agonist/partial agonist or agonist/antagonist analgesics may also precipitate withdrawal symptoms and/or reduced analgesic efficacy in patients following prolonged therapy with mu opioid agonists.

• Abuse/misuse/diversion: Use with caution in patients with a history of substance or alcohol use disorder; potential for drug dependency exists. Other factors associated with increased risk include younger age and psychotropic medication use. Consider offering naloxone prescriptions in patients with factors associated with an increased risk for overdose, such as history of overdose or substance use disorder, higher opioid dosages (≥50 morphine milligram equivalents/day orally), and concomitant benzodiazepine use (CDC [Dowell 2016]).

• Accidental exposure (intranasal): Respiratory depression and death may occur with accidental exposure of even 1 dose of butorphanol nasal spray.

• Appropriate use: Chronic pain (outside of end-of-life or palliative care, active cancer treatment, sickle cell disease, or medication-based opioid use disorder treatment) in outpatient setting in adults: Opioids should not be used as first-line therapy for chronic pain management (pain >3-month duration or beyond time of normal tissue healing) due to limited short-term benefits, undetermined long-term benefits, and association with serious risks (eg, overdose, MI, auto accidents, risk of developing opioid use disorder). Preferred management includes nonpharmacologic therapy and nonopioid therapy (eg, nonsteroidal anti-inflammatory drugs, acetaminophen, certain antiseizure medications, and antidepressants). If opioid therapy is initiated, it should be combined with nonpharmacologic and nonopioid therapy, as appropriate. Prior to initiation, known risks of opioid therapy should be discussed and realistic treatment goals for pain/function should be established, including consideration for discontinuation if benefits do not outweigh risks. Therapy should be continued only if clinically meaningful improvement in pain/function outweighs risks. Therapy should be initiated at the lowest effective dosage using immediate-release opioids (instead of extended-release/long-acting opioids). Risk associated with use increases with higher opioid dosages. Risks and benefits should be re-evaluated when increasing dosage to ≥50 morphine milligram equivalents (MME)/day orally; dosages ≥90 MME/day orally should be avoided unless carefully justified (CDC [Dowell 2016]).

• Naloxone access: Discuss the availability of naloxone with all patients who are prescribed opioid analgesics, as well as their caregivers, and consider prescribing it to patients who are at increased risk of opioid overdose. These include patients who are also taking benzodiazepines or other CNS depressants, have an opioid use disorder (OUD) (current or history of), or have experienced a previous opioid overdose. Additionally, health care providers should consider prescribing naloxone to patients prescribed medications to treat OUD; patients at risk of opioid overdose even if they are not taking an opioid analgesic or medication to treat OUD; and patients taking opioids, including methadone or buprenorphine for OUD, if they have household members, including children, or other close contacts at risk for accidental ingestion or opioid overdose. Inform patients and caregivers on options for obtaining naloxone (eg, by prescription, directly from a pharmacist, a community-based program) as permitted by state dispensing and prescribing guidelines. Educate patients and caregivers on how to recognize respiratory depression, proper administration of naloxone, and getting emergency help.

• Optimal regimen: An opioid-containing analgesic regimen should be tailored to each patient's needs and based upon the type of pain being treated (acute versus chronic), the route of administration, degree of tolerance for opioids (naive versus chronic user), age, weight, and medical condition. The optimal analgesic dose varies widely among patients; doses should be titrated to pain relief/prevention.

• Surgery: Opioids decrease bowel motility; monitor for decrease bowel motility in postop patients receiving opioids.

Metabolism/Transport Effects

Substrate of CYP3A4 (minor); Note: Assignment of Major/Minor substrate status based on clinically relevant drug interaction potential

Drug Interactions

Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the Lexicomp drug interactions program by clicking on the “Launch drug interactions program” link above.

Alizapride: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Alvimopan: Opioid Agonists may enhance the adverse/toxic effect of Alvimopan. This is most notable for patients receiving long-term (i.e., more than 7 days) opiates prior to alvimopan initiation. Management: Alvimopan is contraindicated in patients receiving therapeutic doses of opioids for more than 7 consecutive days immediately prior to alvimopan initiation. Risk D: Consider therapy modification

Amphetamines: May enhance the analgesic effect of Opioid Agonists. Risk C: Monitor therapy

Anticholinergic Agents: May enhance the adverse/toxic effect of Opioid Agonists. Specifically, the risk for constipation and urinary retention may be increased with this combination. Risk C: Monitor therapy

Azelastine (Nasal): May enhance the CNS depressant effect of CNS Depressants. Risk X: Avoid combination

Blonanserin: CNS Depressants may enhance the CNS depressant effect of Blonanserin. Management: Use caution if coadministering blonanserin and CNS depressants; dose reduction of the other CNS depressant may be required. Strong CNS depressants should not be coadministered with blonanserin. Risk D: Consider therapy modification

Brimonidine (Topical): May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Bromopride: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Bromperidol: May enhance the CNS depressant effect of CNS Depressants. Risk X: Avoid combination

Buprenorphine: Opioids (Mixed Agonist / Antagonist) may diminish the therapeutic effect of Buprenorphine. This combination may also induce opioid withdrawal. Risk X: Avoid combination

Cannabinoid-Containing Products: CNS Depressants may enhance the CNS depressant effect of Cannabinoid-Containing Products. Risk C: Monitor therapy

Chlormethiazole: May enhance the CNS depressant effect of CNS Depressants. Management: Monitor closely for evidence of excessive CNS depression. The chlormethiazole labeling states that an appropriately reduced dose should be used if such a combination must be used. Risk D: Consider therapy modification

Chlorphenesin Carbamate: May enhance the adverse/toxic effect of CNS Depressants. Risk C: Monitor therapy

CNS Depressants: May enhance the CNS depressant effect of Opioid Agonists. Management: Avoid concomitant use of opioid agonists and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Risk D: Consider therapy modification

CYP3A4 Inducers (Strong): May decrease the serum concentration of Butorphanol. Risk C: Monitor therapy

CYP3A4 Inhibitors (Strong): May increase the serum concentration of Butorphanol. Risk C: Monitor therapy

Daridorexant: May enhance the CNS depressant effect of CNS Depressants. Management: Dose reduction of daridorexant and/or any other CNS depressant may be necessary. Use of daridorexant with alcohol is not recommended, and the use of daridorexant with any other drug to treat insomnia is not recommended. Risk D: Consider therapy modification

Desmopressin: Opioid Agonists may enhance the hyponatremic effect of Desmopressin. Risk C: Monitor therapy

DexmedeTOMIDine: CNS Depressants may enhance the CNS depressant effect of DexmedeTOMIDine. Management: Monitor for increased CNS depression during coadministration of dexmedetomidine and CNS depressants, and consider dose reductions of either agent to avoid excessive CNS depression. Risk D: Consider therapy modification

Difelikefalin: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Dimethindene (Topical): May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Diuretics: Opioid Agonists may enhance the adverse/toxic effect of Diuretics. Opioid Agonists may diminish the therapeutic effect of Diuretics. Risk C: Monitor therapy

Droperidol: May enhance the CNS depressant effect of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (eg, opioids, barbiturates) with concomitant use. Risk D: Consider therapy modification

Eluxadoline: Opioid Agonists may enhance the constipating effect of Eluxadoline. Risk X: Avoid combination

Flunarizine: CNS Depressants may enhance the CNS depressant effect of Flunarizine. Risk X: Avoid combination

Flunitrazepam: CNS Depressants may enhance the CNS depressant effect of Flunitrazepam. Management: Reduce the dose of CNS depressants when combined with flunitrazepam and monitor patients for evidence of CNS depression (eg, sedation, respiratory depression). Use non-CNS depressant alternatives when available. Risk D: Consider therapy modification

Gastrointestinal Agents (Prokinetic): Opioid Agonists may diminish the therapeutic effect of Gastrointestinal Agents (Prokinetic). Risk C: Monitor therapy

HydrOXYzine: May enhance the CNS depressant effect of CNS Depressants. Management: Consider a decrease in the CNS depressant dose, as appropriate, when used together with hydroxyzine. Increase monitoring of signs/symptoms of CNS depression in any patient receiving hydroxyzine together with another CNS depressant. Risk D: Consider therapy modification

Kava Kava: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Kratom: May enhance the CNS depressant effect of CNS Depressants. Risk X: Avoid combination

Lemborexant: May enhance the CNS depressant effect of CNS Depressants. Management: Dosage adjustments of lemborexant and of concomitant CNS depressants may be necessary when administered together because of potentially additive CNS depressant effects. Close monitoring for CNS depressant effects is necessary. Risk D: Consider therapy modification

Lisuride: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Lofexidine: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Magnesium Sulfate: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Methotrimeprazine: CNS Depressants may enhance the CNS depressant effect of Methotrimeprazine. Methotrimeprazine may enhance the CNS depressant effect of CNS Depressants. Management: Reduce the usual dose of CNS depressants by 50% if starting methotrimeprazine until the dose of methotrimeprazine is stable. Monitor patient closely for evidence of CNS depression. Risk D: Consider therapy modification

Metoclopramide: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

MetyroSINE: CNS Depressants may enhance the sedative effect of MetyroSINE. Risk C: Monitor therapy

Minocycline (Systemic): May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Monoamine Oxidase Inhibitors: Butorphanol may enhance the serotonergic effect of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Risk X: Avoid combination

Nalfurafine: Opioid Agonists may enhance the adverse/toxic effect of Nalfurafine. Opioid Agonists may diminish the therapeutic effect of Nalfurafine. Risk C: Monitor therapy

Nalmefene: May diminish the therapeutic effect of Opioid Agonists. Management: Avoid the concomitant use of oral nalmefene and opioid agonists. Discontinue oral nalmefene 1 week prior to any anticipated use of opioid agonists. If combined, larger doses of opioid agonists will likely be required. Risk D: Consider therapy modification

Naltrexone: May diminish the therapeutic effect of Opioid Agonists. Management: Seek therapeutic alternatives to opioids. See full drug interaction monograph for detailed recommendations. Risk X: Avoid combination

Olopatadine (Nasal): May enhance the CNS depressant effect of CNS Depressants. Risk X: Avoid combination

Opioid Agonists: Opioids (Mixed Agonist / Antagonist) may diminish the analgesic effect of Opioid Agonists. Management: Seek alternatives to mixed agonist/antagonist opioids in patients receiving pure opioid agonists, and monitor for symptoms of therapeutic failure/high dose requirements (or withdrawal in opioid-dependent patients) if patients receive these combinations. Risk X: Avoid combination

Opioid Agonists: CNS Depressants may enhance the CNS depressant effect of Opioid Agonists. Management: Avoid concomitant use of opioid agonists and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Risk D: Consider therapy modification

Orphenadrine: CNS Depressants may enhance the CNS depressant effect of Orphenadrine. Risk X: Avoid combination

Oxomemazine: May enhance the CNS depressant effect of CNS Depressants. Risk X: Avoid combination

Oxybate Salt Products: CNS Depressants may enhance the CNS depressant effect of Oxybate Salt Products. Management: Consider alternatives to this combination when possible. If combined, dose reduction or discontinuation of one or more CNS depressants (including the oxybate salt product) should be considered. Interrupt oxybate salt treatment during short-term opioid use Risk D: Consider therapy modification

Paraldehyde: CNS Depressants may enhance the CNS depressant effect of Paraldehyde. Risk X: Avoid combination

Pegvisomant: Opioid Agonists may diminish the therapeutic effect of Pegvisomant. Risk C: Monitor therapy

Piribedil: CNS Depressants may enhance the CNS depressant effect of Piribedil. Risk C: Monitor therapy

Pramipexole: CNS Depressants may enhance the sedative effect of Pramipexole. Risk C: Monitor therapy

Procarbazine: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Ramosetron: Opioid Agonists may enhance the constipating effect of Ramosetron. Risk C: Monitor therapy

Ropeginterferon Alfa-2b: CNS Depressants may enhance the adverse/toxic effect of Ropeginterferon Alfa-2b. Specifically, the risk of neuropsychiatric adverse effects may be increased. Management: Avoid coadministration of ropeginterferon alfa-2b and other CNS depressants. If this combination cannot be avoided, monitor patients for neuropsychiatric adverse effects (eg, depression, suicidal ideation, aggression, mania). Risk D: Consider therapy modification

ROPINIRole: CNS Depressants may enhance the sedative effect of ROPINIRole. Risk C: Monitor therapy

Rotigotine: CNS Depressants may enhance the sedative effect of Rotigotine. Risk C: Monitor therapy

Rufinamide: May enhance the adverse/toxic effect of CNS Depressants. Specifically, sleepiness and dizziness may be enhanced. Risk C: Monitor therapy

Samidorphan: May diminish the therapeutic effect of Opioid Agonists. Risk X: Avoid combination

Serotonergic Agents (High Risk): Opioid Agonists may enhance the serotonergic effect of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor therapy

Sincalide: Drugs that Affect Gallbladder Function may diminish the therapeutic effect of Sincalide. Management: Consider discontinuing drugs that may affect gallbladder motility prior to the use of sincalide to stimulate gallbladder contraction. Risk D: Consider therapy modification

Somatostatin Analogs: Opioid Agonists may diminish the analgesic effect of Somatostatin Analogs. Opioid Agonists may enhance the analgesic effect of Somatostatin Analogs. Risk C: Monitor therapy

Succinylcholine: May enhance the bradycardic effect of Opioid Agonists. Risk C: Monitor therapy

Suvorexant: CNS Depressants may enhance the CNS depressant effect of Suvorexant. Management: Dose reduction of suvorexant and/or any other CNS depressant may be necessary. Use of suvorexant with alcohol is not recommended, and the use of suvorexant with any other drug to treat insomnia is not recommended. Risk D: Consider therapy modification

Thalidomide: CNS Depressants may enhance the CNS depressant effect of Thalidomide. Risk X: Avoid combination

Valerian: May enhance the CNS depressant effect of CNS Depressants. Risk C: Monitor therapy

Zolpidem: CNS Depressants may enhance the CNS depressant effect of Zolpidem. Management: Reduce the Intermezzo brand sublingual zolpidem adult dose to 1.75 mg for men who are also receiving other CNS depressants. No such dose change is recommended for women. Avoid use with other CNS depressants at bedtime; avoid use with alcohol. Risk D: Consider therapy modification

Reproductive Considerations

Long-term opioid use may cause secondary hypogonadism, which may lead to sexual dysfunction or infertility (Brennan 2013).

Pregnancy Considerations

Butorphanol crosses the placenta

Butorphanol can be detected in neonatal serum following maternal IM injection prior to delivery (Pittman 1980).

According to some studies, maternal use of opioids may be associated with birth defects (including neural tube defects, congenital heart defects, and gastroschisis), poor fetal growth, stillbirth, and preterm delivery (CDC [Dowell 2016]). Opioids used as part of obstetric analgesia/anesthesia during labor and delivery may temporarily affect the fetal heart rate (ACOG 209 2019).

Prolonged use of butorphanol during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated, and requires management according to protocols developed by neonatology experts. If opioid use is required for a prolonged period during pregnancy, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available. If chronic opioid exposure occurs in pregnancy, adverse events in the newborn (including withdrawal) may occur (Chou 2009). Symptoms of neonatal abstinence syndrome (NAS) following opioid exposure may be autonomic (eg, fever, temperature instability), gastrointestinal (eg, diarrhea, vomiting, poor feeding/weight gain), or neurologic (eg, high-pitched crying, hyperactivity, increased muscle tone, increased wakefulness/abnormal sleep pattern, irritability, sneezing, seizure, tremor, yawning) (Dow 2012; Hudak 2012). Mothers who are physically dependent on opioids may give birth to infants who are also physically dependent. Opioids may cause respiratory depression and psychophysiologic effects in the neonate; newborns of mothers receiving opioids during labor should be monitored.

Butorphanol injection is approved for the management of pain during labor; apnea or respiratory distress in the newborn may occur. Opioids used as part of obstetric analgesia/anesthesia during labor and delivery may temporarily affect the fetal heart rate (ACOG 209 2019). The manufacturer recommends that caution be used if abnormal fetal heart rate patterns are present.

The ACOG recommends that pregnant patients should not be denied medically necessary surgery, regardless of trimester. If the procedure is elective, it should be delayed until after delivery (ACOG 775 2019).

Breastfeeding Considerations

Butorphanol is present in breast milk.

Butorphanol concentrations in breast milk were evaluated in six women following a single maternal dose of 2 mg IM administered 79 ± 20 hours after delivery. The highest concentrations appeared 1 hour after the dose (1.5 ± 0.9 ng/mL) and decreased to 0.3 ± 0.2 ng/mL 6 hours after the dose (Pittman 1980).

According to the manufacturer, the decision to breastfeed during therapy should consider the risk of infant exposure, the benefits of breastfeeding to the infant, and benefits of treatment to the mother. Nonopioid analgesics are preferred for breastfeeding patients who require pain control peripartum or for surgery outside of the postpartum period. Use of butorphanol may be considered when an opioid is needed (ABM [Martin 2018]; ABM [Reece-Stremtan 2017]). In general, a single occasional dose of an opioid analgesic may be compatible with breastfeeding (WHO 2002). Breastfeeding patients using opioids for postpartum pain should monitor their infants for drowsiness, sedation, feeding difficulties, or limpness (ACOG 209 2019). Withdrawal symptoms may occur when maternal use is discontinued or breastfeeding is stopped.

The Academy of Breast Feeding Medicine recommends postponing elective surgery until milk supply and breastfeeding are established. Milk should be expressed ahead of surgery when possible. In general, when the child is healthy and full term, breastfeeding may resume, or milk may be expressed once the mother is awake and in recovery. For children who are at risk for apnea, hypotension, or hypotonia, milk may be saved for later use when the child is at lower risk (ABM [Reece-Stremtan 2017]).

Monitoring Parameters

Pain relief, respiratory and mental status, BP; bowel function; signs/symptoms of addiction, abuse, or misuse; signs or symptoms of hypogonadism or hypoadrenalism (Brennan 2013).

Alternate recommendations: Long-term therapy (eg, outside of end-of-life or palliative care, active cancer treatment, sickle cell disease, or medication-based opioid use disorder treatment): Evaluate benefits/risks of opioid therapy within 1 to 4 weeks of treatment initiation and with dose increases. Re-evaluate benefits/risks every 3 months during therapy or more frequently in patients at increased risk of overdose or opioid use disorder. Urine drug testing is recommended prior to initiation and re-checking should be considered at least yearly (includes controlled prescription medications and illicit drugs of abuse). State prescription drug monitoring program (PDMP) data should be reviewed by clinicians prior to initiation and periodically during therapy (frequency ranging from every prescription to every 3 months) (CDC [Dowell 2016]).

Reference Range

0.7 to 1.5 ng/mL

Mechanism of Action

Agonist of kappa opiate receptors and partial agonist of mu opiate receptors in the CNS, causing inhibition of ascending pain pathways, altering the perception of and response to pain; produces analgesia, respiratory depression, and sedation similar to opioids

Pharmacokinetics

Onset of action: IM, nasal: ≤15 minutes; IV: Within a few minutes

Peak effect: IM, IV: 0.5 to 1 hour; Nasal: 1 to 2 hours

Duration: IM, IV: 3 to 4 hours; Nasal: 4 to 5 hours

Absorption: Rapid and well absorbed

Distribution: Vd: 305 to 901 L

Protein binding: ~80%

Metabolism: Hepatic to major metabolite, hydroxybutorphanol

Bioavailability: Nasal: 60% to 70%

Half-life elimination: IV, nasal: ~2 to 9 hours; Hydroxybutorphanol: ~18 hours

Elderly: IV, nasal: ~3 to 9 hours

Renal impairment (CrCl <30 mL/minute): ~10.5 hours

Hepatic impairment: ~16.8 hours

Time to peak, plasma: IM: 20 to 40 minutes; Nasal: 30 to 60 minutes

Excretion: Primarily urine (70% to 80%; ~5% unchanged); feces (15%)

Pharmacokinetics: Additional Considerations

Altered kidney function: Elimination half-life is approximately doubled and the total body clearance is approximately one-half in patients with CrCl <30 mL/minute.

Hepatic function impairment: Elimination half-life is approximately tripled and total body clearance is approximately one-half. Exposure to butorphanol is significantly greater (about 2-fold).

Older adult: Elimination half-life is increased. Absolute bioavailability of nasal spray is less in elderly women (48%) than in elderly men (75%).

Pricing: US

Solution (Butorphanol Tartrate Injection)

1 mg/mL (per mL): $6.08

2 mg/mL (per mL): $7.44

Solution (Butorphanol Tartrate Nasal)

10 mg/mL (per mL): $38.53

Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.

Brand Names: International
  • Beforal (CZ, PL);
  • Bunol (KR);
  • Butodol (IN);
  • Butophan (KR);
  • Butrum (IN);
  • Moradol (PL);
  • Nuo Yang (CN);
  • Orfadol (PH);
  • Stadol (JP, PL, RU);
  • Verstadol (ES);
  • Ziphanol (PH)


For country code abbreviations (show table)
  1. American College of Obstetricians and Gynecologists (ACOG). ACOG committee opinion no. 775: nonobstetric surgery during pregnancy. Obstet Gynecol. 2019;133(4):e285-e286. [PubMed 30913200]
  2. American College of Obstetricians and Gynecologists (ACOG). ACOG practice bulletin no. 209: obstetric analgesia and anesthesia. Obstet Gynecol. 2019;133(3):e208-e225. [PubMed 30801474]
  3. Berna C, Kulich RJ, Rathmell JP. Tapering long-term opioid therapy in chronic noncancer pain: evidence and recommendations for everyday practice. Mayo Clin Proc. 2015;90(6):828-842. doi: 10.1016/j.mayocp.2015.04.003. [PubMed 26046416]
  4. Brennan MJ. The effect of opioid therapy on endocrine function. Am J Med. 2013;126(3)(suppl 1):S12-S18. doi: 10.1016/j.amjmed.2012.12.001. [PubMed 23414717]
  5. Butorphanol tartrate injection [prescribing information]. Lake Forest, IL: Hospira Inc; June 2019.
  6. Butorphanol tartrate nasal solution [prescribing information]. Eatontown, NJ: West-Ward Pharmaceuticals Corp; August 2018.
  7. Butorphanol tartrate nasal spray [prescribing information]. Weston, FL: Apotex Corp; January 2021.
  8. Butorphanol tartrate nasal spray [product monograph]. Vaughan, Ontario, Canada: AA Pharma Inc; May 2022.
  9. Centers for Disease Control and Prevention (CDC). Common elements in guidelines for prescribing opioids for chronic pain. https://www.cdc.gov/drugoverdose/pdf/common_elements_in_guidelines_for_prescribing_opioids-a.pdf. Published 2015. Accessed September 13, 2018.
  10. Chou R, Fanciullo GJ, Fine PG, et al, "Clinical Guidelines For the Use of Chronic Opioid Therapy in Chronic Noncancer Pain," J Pain, 2009, 10(2):113-30. [PubMed 19187889]
  11. Chou R, Gordon DB, de Leon-Casasola OA, et al. Management of postoperative pain: a clinical practice guideline from the American Pain Society, the American Society of Regional Anesthesia and Pain Medicine, and the American Society of Anesthesiologists' committee on regional anesthesia, executive committee, and administrative council. J Pain. 2016;17(2):131-157. doi:10.1016/j.jpain.2015.12.008 [PubMed 26827847]
  12. Debono M, Chan S, Rolfe C, Jones TH. Tramadol-induced adrenal insufficiency. Eur J Clin Pharmacol. 2011;67(8):865-867. [PubMed 21243342]
  13. Dow K, Ordean A, Murphy-Oikonen J, et al, "Neonatal Abstinence Syndrome Clinical Practice Guidelines For Ontario," J Popul Ther Clin Pharmacol, 2012, 19(3):e488-506. [PubMed 23241498]
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  15. Gaver RC, Vasiljev M, Wong H, et al, “Disposition of Parenteral Butorphanol in Man,” Drug Metab Dispos, 1980, 8(4):230-5. [PubMed 6105056]
  16. Hill MV, Stucke RS, McMahon ML, Beeman JL, Barth RJ Jr. An educational intervention decreases opioid prescribing after general surgical operations. Ann Surg. 2018;267(3):468-472. doi:10.1097/SLA.0000000000002198 [PubMed 28267689]
  17. Hoskin PJ, Hanks GW. Opioid agonists-antagonist drugs in acute and chronic pain states. Drugs. 1991;41(3):326-344. doi:10.2165/00003495-199141030-00002 [PubMed 1711441]
  18. Hudak ML, Tan RC, Committee On Drugs, et al, "Neonatal Drug Withdrawal," Pediatrics, 2012, 129(2):e540-60. [PubMed 22291123]
  19. Martin E, Vickers B, Landau R, Reece-Stremtan S. ABM clinical protocol #28, peripartum analgesia and anesthesia for the breastfeeding mother. Breastfeed Med. 2018;13(3):164-171. [PubMed 29595994]
  20. Pittman KA, Smyth RD, Losada M, Zighelboim I, Maduska AL, Sunshine A. Human perinatal distribution of butorphanol. Am J Obstet Gynecol. 1980;138(7 Pt 1):797-800. [PubMed 7446613]
  21. Reece-Stremtan S, Campos M, Kokajko L; Academy of Breastfeeding Medicine. ABM clinical protocol #15: analgesia and anesthesia for the breastfeeding mother, revised 2017. Breastfeed Med. 2017;12(9):500-506. [PubMed 29624435]
  22. Sevarino K. Medically supervised opioid withdrawal during treatment for addiction. Post TW, ed. UpToDate. Waltham, MA: UpToDate Inc. http://www.uptodate.com. Accessed March 29, 2022.
  23. U.S. Department of Health and Human Services. HHS guide for clinicians on the appropriate dosage reduction or discontinuation of long-term opioid analgesics. October 2019. https://www.hhs.gov/opioids/sites/default/files/2019-10/Dosage_Reduction_Discontinuation.pdf.
  24. World Health Organization (WHO). Breastfeeding and maternal medication, recommendations for drugs in the Eleventh WHO Model List of Essential Drugs. 2002. Available at http://apps.who.int/medicinedocs/pdf/s5406e/s5406e.pdf
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