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Fosfomycin oral

Updated 2 Feb 2023 | Urinary-tract infections


Oral formulations of fosfomycin.

Drugs List

  • ALEXI 3g granules
  • fosfomycin 3g granules for oral solution
  • MONURIL 3g granules for oral solution
  • Therapeutic Indications


    Prophylaxis of urinary infection during instrumental procedures
    Uncomplicated lower urinary tract infection

    The treatment of acute, uncomplicated cystitis in women and female adolescents.

    Perioperative antibiotic prophylaxis for transrectal prostate biopsy in adult men.



    Acute, uncomplicated cystitis:
    Take one, 3g sachet, as a single dose dissolved in water.

    Perioperative antibiotic prophylaxis for transrectal prostate biopsy:
    Take one, 3g sachet, as a single dose dissolved in water, 3 hours before the procedure. A second 3g sachet 24 hours after procedure.


    12 years and older
    Acute, uncomplicated cystitis:
    Take one, 3g sachet, as a single dose dissolved in water.


    Children under 12 years
    Hereditary fructose intolerance
    Renal impairment - creatinine clearance below 10ml/minute

    Precautions and Warnings

    Glucose-galactose malabsorption syndrome

    Advise ability to drive/operate machinery may be affected by side effects
    Consult national/regional policy on the use of anti-infectives
    Preparation contains sucrose
    Advise patient to have no food for 2 hours before or after dose
    Consider pseudomembranous colitis if patient presents with diarrhoea
    Discontinue if diarrhoea associated to Clostridioides difficile occurs
    Discontinue if serious allergic or anaphylactic reaction occurs
    Not licensed for all indications in all age groups

    Clostridioides difficile-associated colitis and pseudo-membranous colitis have been observed with fosfomycin and may range in severity from mild to life-threatening. Therefore, it is important to consider this diagnosis in patients who present with diarrhoea during or after the administration of fosfomycin. Medicinal products that inhibit peristalsis should not be given.

    Persistent infections, are often due to complicated urinary tract infections or the prevalence of resistant pathogens (e.g. Staphylococcus saprophyticus). In general, urinary tract infections in male patients have to be considered as complicated UTIs, for which fosfomycin is not indicated.

    Pregnancy and Lactation


    Use fosfomycin with caution during pregnancy.

    The manufacturer recommends advises that fosfomycin should only be used during pregnancy if clearly necessary. At the time of writing, there is limited data regarding the safety of fosfomycin treatment during the 1st trimester of pregnancy. Fosfomycin crosses the placenta. Animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity.


    Use fosfomycin with caution during breastfeeding.

    The manufacturer advises that a single dose of fosfomycin can be used during breastfeeding if clearly necessary. Fosfomycin is excreted in human milk in low quantities. LactMed (2020) suggests fosfomycin produces low levels in breast milk and would not be expected to cause any adverse effects in breastfed infants, especially if the infant is older than 2 months. Briggs (2015) suggests the risk to the nursing infant is unknown, modification of the infant's bowel flora may occur.


    Advise patient to take on an empty stomach, 2 to 3 hours before or after a meal. Preferably taken before retiring and after emptying the bladder. Dissolve dose into a glass of water and take straight after preparing.

    Advise patient for the indication of acute, uncomplicated cystitis in women and female adolescents that fosfomycin should be taken preferably before bedtime and after emptying the bladder.

    Advise patient, ability to drive and operate machinery may be affected by side effects.

    Side Effects

    Abdominal pain
    Anaphylactic reaction
    Anaphylactic shock
    Hypersensitivity reactions
    Pseudomembranous colitis
    Vulvovaginal irritation


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: October 2021.

    Reference Sources

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 10th edition (2015) ed. Briggs, G., Freeman, R. Wolters Kluwer Health, Philadelphia.

    Summary of Product Characteristics: Alexi 3g granules for oral solution. ParaPharm Development Limited. Revised May 2021.

    Summary of Product Characteristics: Monuril 3g granules for oral solution. Profile Pharma Limited. Revised May 2021.

    NICE Evidence Services Available at: Last accessed: 13 October 2021

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Fosfomycin. Last revised: 21 September 2020
    Last accessed: 14 October 2021

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