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URL of this page: https://medlineplus.gov/druginfo/meds/a697008.html

Fosfomycin

pronounced as (fos foe mye' sin)

Why is this medication prescribed?

Fosfomycin is an antibiotic used to treat infections of the urinary tract.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Fosfomycin comes as granules to be mixed with water and then taken by mouth. Do not take the dry granules by mouth without first diluting them in water. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take fosfomycin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

To prepare a dose, pour the entire contents of a single-dose packet into a glass and add 3 to 4 ounces (90 to 120 milliliters) of cold water. Stir to dissolve. Do not use hot water. The dose should be taken by mouth as soon as it is prepared.

What special precautions should I follow?

Before taking fosfomycin,

  • tell your doctor and pharmacist if you are allergic to fosfomycin or any other drugs.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking fosfomycin. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had asthma or liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking fosfomycin, call your doctor.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Fosfomycin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • nausea
  • diarrhea
  • headache
  • vaginal itching
  • runny nose
  • back pain

If you experience any of the following symptoms, call your doctor immediately:

  • fever
  • rash
  • joint pain
  • swelling of the mouth or tongue
  • yellowing of the skin or eyes

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your response to fosfomycin

Do not let anyone else take your medication. Your prescription is probably not refillable. If you still have symptoms of infection after you finish the fosfomycin, call your doctor.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

Brand names

  • Monurol® Sachet
Last Revised - 12/15/2017