Carcinogenicity has been seen in mice and rats treated chronically with metronidazole, another nitroimidazole agent. Although such data have not been reported for tinidazole, the two drugs are structurally related and have similar biologic effects. Limit use to approved indications only. Avoid chronic use.
Amebiasis, intestinal: Oral: 2 g once daily for 3 days.
Amebiasis, liver abscess: Oral: 2 g once daily for 3 to 5 days.
Bacterial vaginosis (alternative agent):
Note: Treatment is generally not warranted for asymptomatic patients who are not pregnant (CDC [Workowski 2021]).
Oral: 1 g once daily for 5 days or 2 g once daily for 2 days (CDC [Workowski 2021]; Livengood 2007); some experts prefer 1 g once daily for 5 days due to improved efficacy and tolerability (Livengood 2007; Sobel 2022).
For multiple disease recurrences, 500 mg twice daily for 7 days in combination with or prior to a multiweek course of boric acid, followed by suppressive topical therapy (CDC [Workowski 2021]; Reichman 2009; Sobel 2022).
Giardiasis: Oral: 2 g as a single dose.
Helicobacter pylori eradication (off-label use): Oral:
American College of Gastroenterology guidelines (Chey 2007; Chey 2017):
Concomitant regimen: 500 mg twice daily in combination with clarithromycin 500 mg twice daily, amoxicillin 1 g twice daily, and a standard-dose proton pump inhibitor twice daily; continue regimen for 10 to 14 days.
Sequential regimen: Amoxicillin 1 g twice daily plus a standard-dose proton pump inhibitor twice daily for 5 to 7 days; then follow with clarithromycin 500 mg twice daily, tinidazole 500 mg twice daily, and a standard-dose proton pump inhibitor daily for 5 to 7 days.
Hybrid regimen: Amoxicillin 1 g twice daily plus a standard-dose proton pump inhibitor twice daily for 7 days; then follow with amoxicillin 1 g twice daily, clarithromycin 500 mg twice daily, tinidazole 500 mg twice daily, and a standard-dose proton pump inhibitor twice daily for 7 days.
Trichomoniasis (index case and sex partner):
Initial treatment (alternative agent): Oral: 2 g as a single dose (CDC [Workowski 2021]) or 500 mg twice daily for 5 days (WHO 2021).
Refractory infection (off label):
Note: Patients with suspected reinfection because of re-exposure to an untreated partner may receive a regimen used for initial treatment. For others, clinicians may request a kit from the CDC to perform drug-resistant testing (CDC [Workowski 2021]).
Females without re -exposure: Oral: 2 g once daily for 7 days (CDC [Workowski 2021]).
Females with infection refractory to multiple prior regimens:
Combination therapy with oral and intravaginal tinidazole:
Oral: 2 g once daily in combination with intravaginal tinidazole for 14 days (CDC [Workowski 2021]).
Intravaginal: 500 mg twice daily in combination with oral tinidazole for 14 days (CDC [Workowski 2021]; Sobel 2001).
Combination therapy with oral tinidazole and intravaginal paromomycin or boric acid: Oral: 1 g 3 times daily for 14 days in combination with intravaginal paromomycin for 14 days (CDC [Workowski 2021]; Henien 2019; Keating 2015) or intravaginal boric acid for 28 days (Salas 2019).
No dosage adjustment necessary.
Hemodialysis: An additional dose equal to ½ the usual dose, should be administered at the end of hemodialysis if tinidazole is administered prior to hemodialysis on a dialysis day.
There are no dosage adjustments provided in the manufacturer’s labeling (has not been studied); use with caution.
(For additional information see "Tinidazole: Pediatric drug information")
Amebiasis, intestinal: Children >3 years and Adolescents: Oral: 50 mg/kg/dose once daily for 3 days; maximum daily dose: 2,000 mg/day; for patients with severe and extraintestinal disease, administer for 5 days (Red Book [AAP 2018]).
Amebiasis, liver abscess: Children >3 years and Adolescents: Oral: 50 mg/kg/day for 3 to 5 days; maximum daily dose: 2,000 mg/day.
Bacterial vaginosis: Adolescents: Oral: 2,000 mg once daily for 2 days or 1,000 mg once daily for 5 days (CDC [Workowski 2015]).
Blastocystis hominis infection: Limited data available: Children ≥3 years and Adolescents: Oral: 50 mg/kg as a single dose; maximum dose: 2,000 mg (Red Book [AAP 2018]).
Giardiasis: Children >3 years and Adolescents: Oral: 50 mg/kg as a single dose; maximum dose: 2,000 mg.
Helicobacter pylori infection: Limited data available: Children >3 years and Adolescents: Oral: 20 mg/kg/day in 1 to 2 divided doses for 5 to 7 days in combination with other agents; some studies have used a longer duration of 2 to 6 weeks; maximum daily dose: 1,000 mg/day (Francavilla 2005; Moshkowitz 1998; Nijevitch 2000; Oderda 1992).
Trichomoniasis (CDC [Workowski 2015]):
Primary therapy: Adolescents: Oral: 2,000 mg as a single dose; sexual partners should be treated concomitantly.
Persistent, recurrent, after metronidazole treatment failure: Adolescents: Oral: 2,000 mg once daily for 7 days. Note: Ensure reinfection has not occurred prior to initiation.
Urethritis, nongonococcal (recurrent or persistent urethritis in males who have sex with females and who live in regions where T. vaginalis is prevalent): Adolescents: Oral: 2,000 mg as a single dose. Note: Compliance with initial regimen and lack of reexposure to an untreated sex partner should be excluded prior to use (CDC [Workowski 2015]).
Children >3 years and Adolescents: No dosage adjustment necessary
Hemodialysis: Approximately 43% removed during a 6-hour session; an additional dose equal to 1/2 the usual dose should be administered at the end of hemodialysis if tinidazole is administered prior to hemodialysis on dialysis days
There are no dosage adjustments provided in the manufacturer's labeling (has not been studied); use with caution.
Refer to adult dosing.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, Oral:
Generic: 250 mg, 500 mg
Yes
Oral: Administer with food.
Intravaginal (off-label route): Administer tablet intravaginally (Sobel 2001). Do not use tampons, douches, spermicides, or other vaginal products or have vaginal intercourse during treatment (CDC [Workowski 2021]).
Oral: Administer with food to minimize gastrointestinal adverse effects.
Amebiasis: Treatment of intestinal amebiasis and amebic liver abscess caused by Entamoeba histolytica in adults and pediatric patients older than 3 years.
Limitations of use: Not indicated for the treatment of asymptomatic cyst passage.
Bacterial vaginosis: Treatment of bacterial vaginosis (formerly referred to as Haemophilus vaginitis, Gardnerella vaginitis, nonspecific vaginitis, or anaerobic vaginosis) in adults.
Giardiasis: Treatment of giardiasis caused by Giardia duodenalis (also termed Giardia lamblia) in adults and pediatric patients older than 3 years.
Trichomoniasis: Treatment of trichomoniasis caused by Trichomonas vaginalis; treat partners of infected patients simultaneously to prevent reinfection.
Helicobacter pylori eradication
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified. Adverse reactions reported in pediatric patients and adults.
1% to 10%:
Endocrine & metabolic: Heavy menstrual bleeding (>2%)
Gastrointestinal: Abdominal cramps (≤2%), anorexia (2% to 3%), constipation (≤1%), decreased appetite (>2%), dyspepsia (≤2%), epigastric discomfort (≤2%), flatulence (>2%), nausea (3% to 5%), vomiting (≤2%)
Genitourinary: Dysuria (>2%), pelvic pain (>2%), urinary tract infection (>2%), urine abnormality (>2%), vulvovaginal candidiasis (5%), vulvovaginal disease (discomfort or odor) (>2%)
Nervous system: Bitter taste (≤6%), dizziness (≤1%), fatigue (≤2%), headache (≤1%), malaise (≤2%), metallic taste (≤6%)
Neuromuscular & skeletal: Asthenia (≤2%)
Respiratory: Upper respiratory tract infection (>2%)
<1%:
Gastrointestinal: Hairy tongue
Hematologic & oncologic: Thrombocytopenia
Nervous system: Coma, confusion, depression
Respiratory: Bronchospasm, dyspnea, pharyngitis
Frequency not defined:
Cardiovascular: Flushing, palpitations
Dermatologic: Diaphoresis, pruritus, skin rash, urticaria
Endocrine & metabolic: Increased thirst
Gastrointestinal: Abdominal pain, diarrhea, dysgeusia, oral candidiasis, salivation, stomatitis, tongue discoloration, xerostomia
Genitourinary: Dark urine, vaginal discharge
Hematologic & oncologic: Leukopenia, neutropenia
Hepatic: Increased serum transaminases
Hypersensitivity: Angioedema
Infection: Candidiasis (overgrowth)
Nervous system: Ataxia, burning sensation, drowsiness, insomnia, peripheral neuropathy (transient; includes numbness and paresthesia), seizure, vertigo
Neuromuscular & skeletal: Arthralgia, arthritis, myalgia
Miscellaneous: Fever
Postmarketing:
Dermatologic: Erythema multiforme, Stevens-Johnson syndrome
Hypersensitivity: Hypersensitivity reaction (including acute or severe hypersensitivity reaction)
Hypersensitivity to tinidazole, nitroimidazole derivatives, or any component of the formulation; Cockayne syndrome.
Concerns related to adverse effects:
• Carcinogenic: [US Boxed Warning]: Carcinogenicity has been observed with another nitroimidazole derivative (metronidazole) in animal studies; use should be reserved for approved indications only. Avoid chronic use.
• CNS effects: Seizures and peripheral neuropathy (eg, extremity numbness and paresthesia) have been reported with tinidazole and other nitroimidazole derivatives; discontinue treatment if abnormal neurologic signs or symptoms occur.
• Superinfection: Prolonged use may result in fungal or bacterial superinfection, including C. difficile-associated diarrhea (CDAD), pseudomembranous colitis, and/or vaginal candidiasis. CDAD has been observed >2 months postantibiotic treatment.
Disease-related concerns:
• Blood dyscrasias: Use with caution in patients with current or a history of blood dyscrasias.
• Hepatic impairment: Use with caution in patients with hepatic impairment.
Substrate of CYP3A4 (minor); Note: Assignment of Major/Minor substrate status based on clinically relevant drug interaction potential
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.
Alcohol (Ethyl): Tinidazole may enhance the adverse/toxic effect of Alcohol (Ethyl). A disulfiram-like reaction may occur. Risk X: Avoid combination
Bacillus clausii: Antibiotics may diminish the therapeutic effect of Bacillus clausii. Management: Bacillus clausii should be taken in between antibiotic doses during concomitant therapy. Risk D: Consider therapy modification
BCG (Intravesical): Antibiotics may diminish the therapeutic effect of BCG (Intravesical). Risk X: Avoid combination
BCG Vaccine (Immunization): Antibiotics may diminish the therapeutic effect of BCG Vaccine (Immunization). Risk C: Monitor therapy
Cholera Vaccine: Antibiotics may diminish the therapeutic effect of Cholera Vaccine. Management: Avoid cholera vaccine in patients receiving systemic antibiotics, and within 14 days following the use of oral or parenteral antibiotics. Risk X: Avoid combination
Disulfiram: Tinidazole may enhance the adverse/toxic effect of Disulfiram. Risk X: Avoid combination
Immune Checkpoint Inhibitors: Antibiotics may diminish the therapeutic effect of Immune Checkpoint Inhibitors. Risk C: Monitor therapy
Lactobacillus and Estriol: Antibiotics may diminish the therapeutic effect of Lactobacillus and Estriol. Risk C: Monitor therapy
Sodium Picosulfate: Antibiotics may diminish the therapeutic effect of Sodium Picosulfate. Management: Consider using an alternative product for bowel cleansing prior to a colonoscopy in patients who have recently used or are concurrently using an antibiotic. Risk D: Consider therapy modification
Typhoid Vaccine: Antibiotics may diminish the therapeutic effect of Typhoid Vaccine. Only the live attenuated Ty21a strain is affected. Management: Avoid use of live attenuated typhoid vaccine (Ty21a) in patients being treated with systemic antibacterial agents. Postpone vaccination until 3 days after cessation of antibiotics and avoid starting antibiotics within 3 days of last vaccine dose. Risk D: Consider therapy modification
Peak antibiotic serum concentration lowered and delayed, but total drug absorbed not affected. Management: Administer with food.
Tinidazole crosses the human placenta and enters the fetal circulation (Karhunen 1984).
Bacterial vaginosis and trichomoniasis are associated with adverse pregnancy outcomes and treatment during pregnancy is recommended. However, due to adverse events observed in animal reproduction studies and limited human data, use of agents other than tinidazole in pregnant patients is preferred (CDC [Workowski 2021]).
Tinidazole is present in breast milk.
Breast milk concentrations of tinidazole are similar to those in the maternal serum and decline by 72 hours after the last maternal dose (Evaldson 1985; Männistö 1983; Wood 1982). Due to the potential for adverse events, the manufacturer does not recommend breastfeeding during therapy or for 72 hours after the last tinidazole dose.
The manufacturer recommends that ethanol be avoided during treatment and for 3 days after therapy is complete.
After diffusing into the organism, it is proposed that tinidazole causes cytotoxicity by damaging DNA and preventing further DNA synthesis.
Absorption: Rapid and complete
Distribution: Vd: ~50 L; distributes to most body tissues and fluids; crosses the blood-brain barrier
Protein binding: 12%
Metabolism: Hepatic via CYP3A4 (primarily); undergoes oxidation, hydroxylation and conjugation; forms a metabolite
Half-life elimination: 13.2 hours
Time to peak, plasma: 1.6 hours (fasting, delayed ~2 hours when given with food)
Excretion: Urine (~20% to 25%); feces (~12%)
Tablets (Tinidazole Oral)
250 mg (per each): $5.08
500 mg (per each): $10.15 - $12.69
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.
