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Fosfomycin: Pediatric drug information

Fosfomycin: Pediatric drug information
(For additional information see "Fosfomycin: Drug information" and see "Fosfomycin: Patient drug information")

For abbreviations, symbols, and age group definitions used in Lexicomp (show table)
Brand Names: US
  • Monurol
Brand Names: Canada
  • Ivozfo;
  • JAMP-Fosfomycin;
  • Monurol
Therapeutic Category
  • Antibiotic, Miscellaneous
Dosing: Neonatal

Note: Dosing is for an intravenous product not available in the US.

General dosing, susceptible infections: Fosfomycin sodium (Ivozfo [Canadian product]):

PMA <40 weeks: IV: 100 mg/kg/day in 2 divided doses.

PMA 40 to 44 weeks: IV: 200 mg/kg/day in 3 divided doses.

Dosing adjustment in renal impairment: Term and preterm neonates: There are no neonatal-specific recommendations; based on experience in adult patients, dosage adjustment suggested.

Dosing adjustment in hepatic impairment: Term and preterm neonates: No dosage adjustment necessary.

Dosing: Pediatric

Fosfomycin tromethamine (Monurol):

Urinary tract infection, uncomplicated

Urinary tract infection, uncomplicated: Limited data available: Note: Oral formulation should not be used for pyelonephritis or perinephric abscess.

Children <12 years: Oral: 2,000 mg as a single dose (Baquero-Artigao 2019; Careddu 1987; Principi 1990; Varese 1987).

Children ≥12 years and Adolescents: Oral: 3,000 mg as a single dose (Baquero-Artigao 2019; Stein 1999).

Fosfomycin sodium (Ivozfo [Canadian product]): Note: High-dose regimens (>300 mg/kg/day for ≤40 kg and >16 g/day for >40 kg) may be considered for severe infections known or suspected to be caused by organisms with moderate susceptibility. Data is limited for doses >16 g/day, monitor closely.

Meningitis, bacterial

Meningitis, bacterial: Infants, Children, and Adolescents: IV:

<10 kg: 200 to 300 mg/kg/day in 3 divided doses.

10 to 40 kg: 200 to 400 mg/kg/day in 3 to 4 divided doses.

>40 kg: 16 to 24 g/day in 3 to 4 divided doses; maximum dose: 8 g/dose.

Osteomyelitis

Osteomyelitis: Infants, Children, and Adolescents: IV:

<10 kg: 200 to 300 mg/kg/day in 3 divided doses.

10 to 40 kg: 200 to 400 mg/kg/day in 3 to 4 divided doses.

>40 kg: 12 to 24 g/day in 2 to 3 divided doses; maximum dose: 8 g/dose.

Respiratory tract infection, nosocomial

Respiratory tract infection (lower), nosocomial: Infants, Children, and Adolescents: IV:

<10 kg: 200 to 300 mg/kg/day in 3 divided doses.

10 to 40 kg: 200 to 400 mg/kg/day in 3 to 4 divided doses.

>40 kg: 12 to 24 g/day in 2 to 3 divided doses; maximum dose: 8 g/dose.

Urinary tract infection, complicated

Urinary tract infection, complicated: Infants, Children, and Adolescents: IV:

<10 kg: 200 to 300 mg/kg/day in 3 divided doses.

10 to 40 kg: 200 to 400 mg/kg/day in 3 to 4 divided doses.

>40 kg: 12 to 16 g/day in 2 to 3 divided doses; maximum dose: 8 g/dose.

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: Pediatric

Oral: Fosfomycin tromethamine (Monurol): There are no dosage adjustments provided in the manufacturer's labeling; however, in adults with renal impairment (CrCl 7 to 54 mL/minute) the amount of fosfomycin recovered in the urine was lower, suggesting decreased renal excretion.

IV: Fosfomycin sodium (Ivozfo [Canadian product]):

Infants and Children <12 years: There are no pediatric-specific recommendations; based on experience in adult patients, dosage adjustment suggested.

Children ≥12 years and Adolescents:

CrCl >80 mL/minute: No dosage adjustment necessary.

CrCl >40 to 80 mL/minute: There are no dosage adjustments provided in the manufacturer's labeling; use with caution at recommended doses (especially the higher end of the recommended range).

CrCl 40 mL/minute: Administer 70% of the recommended daily dose (based on indication) in 2 to 3 divided doses; first dose (loading dose) should be doubled but should not exceed 8 g.

CrCl 30 mL/minute: Administer 60% of the recommended daily dose (based on indication) in 2 to 3 divided doses; first dose (loading dose) should be doubled but should not exceed 8 g.

CrCl 20 mL/minute: Administer 40% of the usual recommended daily dose (based on indication) in 2 to 3 divided doses; first dose (loading dose) should be doubled but should not exceed 8 g.

CrCl 10 mL/minute: Administer 20% of the usual recommended daily dose (based on indication) in 1 to 2 divided doses; first dose (loading dose) should be doubled but should not exceed 8 g.

Hemodialysis, intermittent: Patients undergoing hemodialysis every 48 hours should receive fosfomycin 2 g at the end of dialysis.

CVVH (post dilution): No dosage adjustment necessary in patients undergoing postdilution CVVH; there are no dosage adjustments provided in the manufacturer's labeling (has not been studied) for patients undergoing predilution CVVH.

Dosing: Hepatic Impairment: Pediatric

Oral: Fosfomycin tromethamine (Monurol): There are no dosage adjustments provided in the manufacturer's labeling.

IV: Fosfomycin sodium (Ivozfo [Canadian product]): Infants, Children, and Adolescents: No dosage adjustment necessary.

Dosing: Adult

(For additional information see "Fosfomycin: Drug information")

Bloodstream infection

Bloodstream infection: IV [Canadian product]: 12 to 24 g/day in 2 to 3 divided doses (maximum: 8 g/dose). Reserve high-dose regimens (>16 g/day) for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin.

Bone and joint infection

Bone and joint infection: IV [Canadian product]: 12 to 24 g/day in 2 to 3 divided doses (maximum: 8 g/dose). Reserve high-dose regimens (>16 g/day) for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin.

Endocarditis, infective

Endocarditis, infective: IV [Canadian product]: 12 to 24 g/day in 2 to 3 divided doses (maximum: 8 g/dose). Reserve high-dose regimens (>16 g/day) for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin.

Intra-abdominal infection, complicated

Intra-abdominal infection, complicated: IV [Canadian product]: 12 to 24 g/day in 2 to 3 divided doses (maximum: 8 g/dose). Reserve high-dose regimens (>16 g/day) for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin.

Meningitis, bacterial

Meningitis, bacterial: IV [Canadian product]: 16 to 24 g/day in 3 to 4 divided doses (maximum: 8 g/dose). Reserve high-dose regimens (>16 g/day) for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin.

Pneumonia, hospital-acquired or ventilator-associated

Pneumonia, hospital-acquired or ventilator-associated: IV [Canadian product]: 12 to 24 g/day in 2 to 3 divided doses (maximum: 8 g/dose). Reserve high-dose regimens (>16 g/day) for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin.

Prostatitis, chronic bacterial

Prostatitis, chronic bacterial (alternative agent) (off-label use): Note: Reserve for use when other options are not appropriate because of resistance or intolerance. The optimal dose has not been established; the following are some suggested dosing regimens:

Oral: 3 g every 2 to 3 days (Los-Arcos 2015) or 3 g once daily for 1 week followed by 3 g once every 48 hours (Karaiskos 2019). Duration is ≥6 weeks (Karaiskos 2019; Los-Arcos 2015).

Skin and soft tissue infection, complicated

Skin and soft tissue infection, complicated: IV [Canadian product]: 12 to 24 g/day in 2 to 3 divided doses (maximum: 8 g/dose). Reserve high-dose regimens (>16 g/day) for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin.

Urinary tract infection

Urinary tract infection:

Asymptomatic bacteriuria (≥105 CFU per mL) in pregnancy: Oral: 3 g as a single dose (Estebanez 2009; Gupta 2022c; IDSA [Nicolle 2019]).

Cystitis, acute uncomplicated or acute simple cystitis (infection limited to the bladder without signs/symptoms of upper tract, prostate, or systemic infection), treatment: Oral: 3 g as a single dose (Gupta 2022a; Gupta 2022c; manufacturer's labeling). Note: Multidose regimens (eg, 3 g once every 2 to 3 days for 3 doses) have been described, particularly for multidrug-resistant UTIs; however, it is unknown whether these have greater efficacy than single-dose therapy (Babiker 2019; Giancola 2017; Loethen 2017; Neuner 2012; Qiao 2013). Fosfomycin may be less effective than other first-line agents, although data are conflicting (Huttner 2018; IDSA/ESCMID [Gupta 2011]); Medical Letter 1997; Stein 1999; Van Pienbroek 1993).

Cystitis, prophylaxis for recurrent infection (alternative agent): Note: May be considered in nonpregnant women with bothersome, frequently recurrent cystitis despite nonantimicrobial preventive measures. The optimal duration has not been established; duration ranges from 3 to 12 months, with periodic reassessment (AUA/CUA/SUFU [Anger 2019]; Gupta 2022b).

Continuous prophylaxis: Oral: 3 g once every 7 to 10 days (AUA/CUA/SUFU [Anger 2019]; Costantini 2014; Rudenko 2005). Note: Some experts use a shorter dosing interval (eg, every 3 to 4 days), but there is no clinical evidence that this is more effective (Gupta 2022b).

Urinary tract infection, complicated (including pyelonephritis): Note: Some experts reserve use for multidrug-resistant infections when other options are not appropriate because of resistance or intolerance (Grabein 2017; Sastry 2016).

IV [Canadian product]: 12 to 24 g/day in 2 to 3 divided doses (maximum: 8 g/dose) (manufacturer's labeling). Total duration of therapy ranges from 5 to 14 days and depends on clinical response and the antimicrobial chosen to complete the regimen (Hooton 2022e; IDSA/ESCMID [Gupta 2011]).

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

The renal dosing recommendations are based upon the best available evidence and clinical expertise. Senior Editorial Team: Bruce Mueller, PharmD, FCCP, FASN, FNKF; Jason Roberts, PhD, BPharm (Hons), B App Sc, FSHP, FISAC; Michael Heung, MD, MS.

Altered kidney function:

Oral: No dosage adjustment necessary for any degree of kidney dysfunction (expert opinion). However, elimination is significantly prolonged in patients with CrCl <50 mL/minute; monitor closely for adverse effects and tolerability, particularly with prolonged therapy.

IV [Canadian product]: Note: Dose recommendations are based on expert opinion derived from pharmacokinetic modeling and limited clinical data (Kaye 2019; Leelawattanachai 2020; manufacturer’s labeling); safety and efficacy of dose adjustments have not been fully evaluated in clinical trials.

Fosfomycin Dose Adjustments for Altered Kidney Function

CrCla

% of indication-specific recommended daily dose to be administered

Frequency

a Estimated using the Cockcroft-Gault formula (manufacturer’s labeling).

b The initial (loading) dose should be increased to twice the maintenance dose; not to exceed 8 g (manufacturer’s labeling). For example, if the maintenance dose is 4 g then the loading dose should be 8 g.

c Reserve dose regimens in the higher part of the range for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin (ie, where higher dosages [>16 g/day] would be considered in patients with normal kidney function) (expert opinion).

40 to 130 mL/minute

100%

2 to 4 divided doses

30 to <40 mL/minuteb

~75% (range: 70% to 80%c)

2 to 3 divided doses

20 to <30 mL/minuteb

~60% (range: 50% to 70%c)

2 to 3 divided doses

10 to <20 mL/minuteb

~40% (range: 30% to 50%c)

2 to 3 divided doses

<10 mL/minuteb

~20% (range: 20% to 30%c)

1 to 2 divided doses

Augmented renal clearance (measured urinary CrCl ≥130 mL/minute/1.73 m2):

Note: Augmented renal clearance (ARC) is a condition that occurs in certain critically ill patients without organ dysfunction and with normal serum creatinine concentrations. Young patients (<55 years of age) admitted post trauma or major surgery are at highest risk for ARC, as well as those with sepsis, burns, or hematologic malignancies. An 8- to 24-hour measured urinary CrCl is necessary to identify these patients (Bilbao-Meseguer 2018; Udy 2010).

IV: Administer maximum indication-specific doses (usually 24 g/day in 3 to 4 divided doses except for urinary tract infections) (expert opinion derived from limited clinical data [Parker 2013; Parker 2015]).

Hemodialysis, intermittent (thrice weekly): Dialyzable (extensively removed) (Bouchet 1985):

Oral: No dosage adjustment necessary. However, elimination is significantly prolonged in patients on dialysis (Bouchet 1985; manufacturer’s labeling); monitor closely for adverse effects and tolerability, particularly with prolonged therapy. When scheduled dose falls on a dialysis day, administer after dialysis (expert opinion).

IV: Initial: 2 to 4 g, then 2 to 4 g three times weekly post hemodialysis (expert opinion derived from Bouchet 1985; manufacturer’s labeling). Reserve higher-dose regimens for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin (ie, where higher dosages [>16 g/day] would be considered in patients with normal kidney function) (expert opinion).

Peritoneal dialysis:

Oral: No dosage adjustment necessary. However, elimination is significantly prolonged in patients on dialysis (Bouchet 1988); monitor closely for toxicity and tolerability, particularly with prolonged therapy (expert opinion).

IV: 2 to 4 g every 48 hours (expert opinion derived from Bouchet 1988; Tobudic 2012). Reserve higher-dose regimens for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin (ie, where higher dosages [>16 g/day] would be considered in patients with normal kidney function) (expert opinion).

CRRT:

Note: Drug clearance is dependent on the effluent flow rate, filter type, and method of renal replacement. Recommendations are based on high-flux dialyzers and effluent flow rates of 20 to 25 mL/kg/hour (or ~1,500 to 3,000 mL/hour) unless otherwise noted. Appropriate dosing requires consideration of adequate drug concentrations (eg, site of infection) and consideration of initial loading doses. Close monitoring of response and adverse reactions due to drug accumulation is important. Note: Very little clinical data.

Oral: No dosage adjustment necessary (expert opinion).

IV: 6 to 8 g every 12 hours (Gattringer 2006; expert opinion). Reserve higher-dose regimens for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin (ie, where higher dosages [>16 g/day] would be considered in patients with normal kidney function) (expert opinion).

PIRRT (eg, sustained, low-efficiency diafiltration):

Note: Drug clearance is dependent on the effluent flow rate, filter type, and method of renal replacement. Appropriate dosing requires consideration of adequate drug concentrations (eg, site of infection) and consideration of initial loading doses. Close monitoring of response and adverse reactions due to drug accumulation is important.

Oral: No dosage adjustment necessary (expert opinion).

IV: 4 to 6 g once daily followed by a 4 to 6 g supplemental dose after each PIRRT session (expert opinion derived from limited clinical data [Schmidt 2016]). Reserve higher-dose regimens for severe infections known or suspected to be caused by organisms with decreased susceptibility to fosfomycin (ie, where higher dosages [>16 g/day] would be considered in patients with normal kidney function) (expert opinion).

Dosing: Hepatic Impairment: Adult

Oral: There are no dosage adjustments provided in the manufacturer's labeling.

IV [Canadian product]: No dosage adjustment necessary.

Dosage Forms: US

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

Packet, Oral:

Monurol: 3 g (1 ea) [orange flavor]

Generic: 3 g (1 ea)

Generic Equivalent Available: US

Yes

Dosage Forms: Canada

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

Packet, Oral:

Monurol: 3 g (3 g) [contains saccharin]

Generic: 3 g (3 g)

Solution Reconstituted, Intravenous:

Ivozfo: 4 g (1 ea)

Administration: Pediatric

Oral: Oral packet: Do not administer in its dry form; must be mixed with water prior to administration. May be administered without regard to meals. Pour contents of 3 g packet into 3 to 4 oz (90 to 120 mL) of water (not hot) and stir to dissolve; the resultant concentration is 25 to 33.3 mg/mL. Measure appropriate volume for desired dose and take immediately. Discard any remaining solution.

IV [Canadian product]: Infuse 2 g dose over ≥15 minutes, 4 g dose over ≥30 minutes, or 8 g dose over ≥60 minutes. Consider extended infusion time (up to 4 hours for the 4 g or 8 g dose) in patients at high risk for hypokalemia.

Administration: Adult

Oral: Always mix with 3 to 4 oz (90 to 120 mL) cool water before ingesting; do not administer in its dry form or mix with hot water. May be administered without regard to meals.

IV [Canadian product]: Infuse 2 g dose over ≥15 minutes; 4 g dose over ≥30 minutes; and 8 g dose over ≥60 minutes. Consider extended infusion time (≤4 hours for the 4 or 8 g dose) or reduction in individual dose with more frequent administration in patients at high risk for hypokalemia.

Storage/Stability

IV [Canadian product]: Store intact vials at 15°C to 30°C (59°F to 86°F). Reconstituted solution may be stored at 2°C to 8°C (36°F to 46°F) for ≤48 hours. Diluted solution may be stored at 2°C to 8°C (36°F to 46°F) or 25°C (77°F) for ≤48 hours. Protect from light.

Oral packet: Store at 25°C (77°F); excursions are permitted between 15°C and 30°C (59°F and 86°F).

Use

Oral granules packet: Treatment of uncomplicated urinary tract infections (acute cystitis) in women due to susceptible strains of Escherichia coli and Enterococcus (FDA approved in adults).

Note: IV products are available in other countries (eg, Canada) and are used for treatment of bacterial meningitis, osteomyelitis, lower respiratory tract infection (nosocomial), and urinary tract infections (complicated) (and any associated bacteremia) in all ages.

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

Monurol may be confused with Monopril

Adverse Reactions

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

1% to 10%:

Central nervous system: Headache (4% to 10%), pain (2%), dizziness (1% to 2%)

Dermatologic: Skin rash (1%)

Gastrointestinal: Diarrhea (9% to 10%), nausea (4% to 5%), abdominal pain (2%), dyspepsia (1% to 2%)

Genitourinary: Vaginitis (6% to 8%), dysmenorrhea (3%)

Neuromuscular & skeletal: Back pain (3%), weakness (1% to 2%)

Respiratory: Rhinitis (5%), pharyngitis (3%)

<1%, postmarketing, and/or case reports: Abnormal stools, anaphylaxis, angioedema, anorexia, aplastic anemia, cholestatic jaundice, constipation, dermatological disease, drowsiness, dysuria, ear disease, exacerbation of asthma, fatigue, fever, flatulence, flu-like symptoms, hearing loss, hematuria, hepatic necrosis, increased serum ALT, insomnia, lymphadenopathy, menstrual disease, migraine, myalgia, nervousness, optic neuritis, paresthesia, pruritus, toxic megacolon, vomiting, xerostomia

Contraindications

Hypersensitivity to fosfomycin or any component of the formulation

Warnings/Precautions

Concerns related to adverse effects:

• Electrolyte abnormalities: IV [Canadian product]: [Canadian Boxed Warning]: The risk of sodium overload and plasma electrolyte imbalances is associated with the use of IV fosfomycin. Use caution when prescribing >16 g/day. Consider sodium content (320 mg per gram of IV fosfomycin) in patients requiring sodium restriction. Use with caution in patients with cardiac insufficiency, hypertension, hyperaldosteronism, hypernatremia, hypoalbuminemia, nephrotic syndrome, pulmonary edema, or hepatic cirrhosis. A high sodium load may also result in decreased serum potassium level, requiring supplementation. Hypokalemia may cause cardiac arrhythmia, edema, hyporeflexia, muscle twitching, tiredness, and weakness.

• Hematologic effects: IV [Canadian product]: Agranulocytosis and neutropenia have been reported with use.

• Hepatic effects: Hepatic injury, including steatosis and hepatitis, has been reported; usually reversible upon discontinuation.

• Hypersensitivity: Hypersensitivity reactions, including anaphylactic shock, have been reported (rare). Discontinue use and institute supportive measures at the first sign(s) of a hypersensitivity reaction.

• Superinfection: Prolonged use may result in fungal or bacterial superinfection, including Clostridioides difficile-associated diarrhea (CDAD) and pseudomembranous colitis; CDAD has been observed >2 months postantibiotic treatment.

Metabolism/Transport Effects

None known.

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.

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

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

Gastrointestinal Agents (Prokinetic): May decrease the serum concentration of Fosfomycin. Risk C: Monitor therapy

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

Dietary Considerations

Some products may contain sodium.

Pregnancy Considerations

Fosfomycin crosses the placenta.

Single dose fosfomycin has been shown to clear bacteria in the urine of pregnant females treated for asymptomatic bacteriuria. However, clinical outcomes (such as pyelonephritis and preterm labor) following single dose therapy are not well studied in pregnancy. When treatment is needed, a 4- to 7-day regimen with an appropriate antibiotic is currently recommended (Nicolle [IDSA 2019]).

Monitoring Parameters

Observe for change in stool frequency.

IV [Canadian product]: Serum electrolytes (especially sodium, potassium, and phosphate) and fluid balance (in particular when using high dose regimens, for all doses in neonates and premature infants, and digitalized patients); renal function; liver function.

Mechanism of Action

As a phosphonic acid derivative, fosfomycin inhibits bacterial wall synthesis (bactericidal) by inactivating the enzyme, pyruvyl transferase, which is critical in the synthesis of cell walls by bacteria.

Pharmacokinetics (Adult data unless noted)

Absorption: Oral: Rapidly absorbed.

Distribution:

Oral: Vd: 90 to 180 L.

IV [Canadian product]: 0.3 L/kg.

Protein binding: None.

Bioavailability: Oral: Fasting: 37%; With food: 30%.

Half-life elimination:

Oral: 3 to 8 hours; CrCl <54 mL/minute: 50 hours; Hemodialysis patients: 40 hours.

IV [Canadian product]: ~2 hours; Elderly and/or critically ill patients: 3.6 to 3.8 hours; CVVHF: 12 hours.

Time to peak, serum: Oral: 2 hours; Within 4 hours with high-fat meal.

Excretion:

Oral: Urine (38% as unchanged drug); feces (18% as unchanged drug).

IV [Canadian product]: Urine (80% to 90% as unchanged drug); feces (<1% as unchanged drug).

Pharmacokinetics: Additional Considerations

Altered kidney function: Oral: Urinary excretion decreases to 11% in patients with CrCl 7 to 54 mL/minute.

Additional Information

Each 1 g of fosfomycin IV (equivalent to 1.32 g fosfomycin sodium) contains 14 mmol (320 mg) sodium.

Pricing: US

Pack (Fosfomycin Tromethamine Oral)

3 g (per each): $72.00 - $100.40

Pack (Monurol Oral)

3 g (per each): $109.52

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
  • Afastural (PL);
  • Dispari (TR);
  • Efomycin (PK);
  • Fasapren (CR, DO, GT, HN, NI, PA, SV);
  • Focimycin (TW);
  • Focin (PK);
  • Focyn (ID);
  • Folsmycin (TW);
  • Fomicyt (GB, GR, HR, IE, NL);
  • Fosday (TR);
  • Fosfocil (CR, DO, GT, HN, MX, NI, PA, PE, SV);
  • Fosfocin (GR, IT);
  • Fosfocina (CU, EC, ES, GR);
  • Fosfocine (FR, VN);
  • Fosfolag (CH);
  • Fosfomin (TH);
  • Fosfomol (PL);
  • Fosforal (IN);
  • Fosforon (EG);
  • Fosfuro (DE);
  • Fosfurol (PY);
  • Fosmicin (RU, TH);
  • Fosmicin-S (JP);
  • Fosmicyn (AR);
  • Fosmidex (ID);
  • Fostren (CO);
  • Fraxemicin-S Kit (KR);
  • Fu An Xin (CN);
  • Infectofos (DE);
  • Monural (BG, HU, PL, RO, RU, SK, UA);
  • Monuril (AT, BE, BR, CH, CO, DE, EG, FR, GB, ID, IE, IT, LU, MT, NL, PT);
  • Monurol (BB, CN, CR, DK, DO, ES, FI, GT, HK, HN, IL, KR, LB, MY, NI, PA, PE, PH, PK, SA, SE, SG, SV, TH, TR, TW, VN);
  • Novellmycin (ID);
  • Rapidnorm (CZ);
  • Solufos (AR, ES);
  • Sonomycin (PK);
  • Ufo (TW);
  • Uninex (HR);
  • Uridoz (FR);
  • Urifos (CZ, HR);
  • Urinex (HR);
  • Urizone (ZA);
  • Veramina (AR);
  • Vnikon (CN)


For country code abbreviations (show table)
  1. Albert X, Huertas I, Pereiró II, Sanfélix J, Gosalbes V, Perrota C. Antibiotics for preventing recurrent urinary tract infection in non-pregnant women. Cochrane Database Syst Rev. 2004;(3):CD001209. doi: 10.1002/14651858.CD001209.pub2. [PubMed 15266443]
  2. Anger J, Lee U, Ackerman AL, et al. Recurrent uncomplicated urinary tract Infections in women: AUA/CUA/SUFU guideline. J Urol. 2019;202(2):282-289. doi: 10.1097/JU.0000000000000296. [PubMed 31042112]
  3. Babiker A, Clarke L, Doi Y, Shields RK. Fosfomycin for treatment of multidrug-resistant pathogens causing urinary tract infection: a real-world perspective and review of the literature [published online June 24, 2019]. Diagn Microbiol Infect Dis. doi: 10.1016/j.diagmicrobio.2019.06.008. [PubMed 31307867]
  4. Baquero-Artigao F, Del Rosal Rabes T. Fosfomycin in the pediatric setting: Evidence and potential indications. Rev Esp Quimioter. 2019;32(suppl 1):S55-S61. [PubMed 31131593]
  5. Bilbao-Meseguer I, Rodríguez-Gascón A, Barrasa H, Isla A, Solinís MÁ. Augmented renal clearance in critically ill patients: a systematic review. Clin Pharmacokinet. 2018;57(9):1107-1121. doi:10.1007/s40262-018-0636-7 [PubMed 29441476]
  6. Bouchet JL, Albin H, Quentin C, et al. Pharmacokinetics of intravenous and intraperitoneal fosfomycin in continuous ambulatory peritoneal dialysis. Clin Nephrol. 1988;29(1):35-40. [PubMed 3383462]
  7. Bouchet JL, Quentin C, Albin H, Vinçon G, Guillon J, Martin-Dupont P. Pharmacokinetics of fosfomycin in hemodialyzed patients. Clin Nephrol. 1985;23(5):218-221. [PubMed 4006330]
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