Generic name: fosfomycin [ FOS-foe-MYE-sin ]
Brand names: Fosfomycin Tromethamine, Monurol
Dosage form: oral granule for reconstitution (3 g)
Drug classes: Miscellaneous antibiotics, Urinary anti-infectives

Medically reviewed by Drugs.com on Dec 21, 2023. Written by Cerner Multum.

What is fosfomycin?

Fosfomycin is an antibiotic that fights infection caused by bacteria.

Fosfomycin is used to treat bladder infections.

Fosfomycin may also be used for purposes not listed in this medication guide.

Fosfomycin side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Fosfomycin may cause serious side effects. Call your doctor at once if you have:

• diarrhea that is watery or bloody; or

• new or worsening bladder symptoms (burning, painful urination).

Common side effects of fosfomycin may include:

• nausea, upset stomach, stomach pain, diarrhea;

• headache, dizziness;

• weakness;

• rash;

• sore throat, runny nose;

• back pain; or

• menstrual pain, vaginal itching or discharge.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

Warnings

Use only as directed. Tell your doctor if you use other medicines or have other medical conditions or allergies.

Before taking this medicine

You should not use fosfomycin if you are allergic to it.

Tell your doctor if you are pregnant or breastfeeding.

Fosfomycin should not be given to a child younger than 12 years old.

Do not share fosfomycin with another person, even if they have the same symptoms you have.

How should I take fosfomycin?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Fosfomycin is usually given in only one dose. Do not take more than a single dose unless your doctor tells you to.

You may take fosfomycin with or without food.

Fosfomycin is a powder medicine that must be mixed with water before using it. Do not take the dry powder without adding water.

Dissolve the powder in 3 to 4 ounces (1/2 cup) of cold water. Stir this mixture and drink all of it right away. To make sure you get the entire dose, add a little more water to the same glass, swirl gently and drink right away.

Do not mix fosfomycin oral powder with hot water.

It may take 2 or 3 days before your symptoms improve.

Call your doctor if your symptoms do not improve within 3 days after treatment, or if you have any other new symptoms.

To be sure fosfomycin is the right antibiotic for the type of infection you have, your urine may need to be tested before and after you take this medicine.

Store at room temperature away from moisture and heat. Keep the powder in its original package until you are ready to mix your dose.

Fosfomycin dosing information

Usual Adult Dose for Cystitis:

3 g (1 sachet) orally once as a single dose

Comments:
-This drug should not be used for the treatment of pyelonephritis or perinephric abscess.

Use: For the treatment of uncomplicated urinary tract infections (acute cystitis) in women due to susceptible strains of Escherichia coli and Enterococcus faecalis

Usual Adult Dose for Urinary Tract Infection:

3 g (1 sachet) orally once as a single dose

Comments:
-This drug should not be used for the treatment of pyelonephritis or perinephric abscess.

Use: For the treatment of uncomplicated urinary tract infections (acute cystitis) in women due to susceptible strains of Escherichia coli and Enterococcus faecalis

What happens if I miss a dose?

Fosfomycin is used as a single dose and does not have a daily dosing schedule.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include hearing problems and altered sense of taste.

What should I avoid while taking fosfomycin?

Antibiotic medicines can cause diarrhea. Tell your doctor if you have diarrhea that is watery or bloody.

What other drugs will affect fosfomycin?

Tell your doctor about all your other medicines, especially metoclopramide.

Other drugs may affect fosfomycin, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Frequently asked questions

• What antibiotics are used to treat UTI?
• How long do antibiotics take to work?

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

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