Antibiotics are responsible for killing bacteria and preventing their reproduction and should always be taken correctly, since if you take one that you do not need, it can cause resistance to some microorganisms.
Fosfomycin is a new class of prescription antibiotic that should not be taken lightly. This antibiotic is used in case of infections produced by bacteria sensitive to this drug. Therefore, we invite you to continue reading this FastlyHealarticle, in which we inform you in detail about this drug, we explain what fosfomycin is , what it is for, its recommended doses and its side effects.
Table of Contents
What is fosfomycin and what is it for
Fosfomycin is a drug that belongs to the group of antibiotics that works by killing bacteria. For this reason, it is known as a bacteriostatic, it acts on gram-positive and gram-negative germs, in addition to aerobic and anaerobic bacteria.
It is used for the treatment and even prevention of uncomplicated acute urinary tract infections of the lower urinary tract, caused by germs sensitive to fosfomycin, in addition to the treatment of cystitis , gastric and respiratory problems.
Presentation of fosfomycin
The way it is presented is in sachets for oral and parenteral for injection:
- Orally, it comes in the form of granules in 3 g sachets to be diluted in water and ingested orally. You should not use hot water but natural, so that it can dissolve quickly. Other laboratories have 500 mg capsules orally in the form of calcium salt.
- For the parenteral route, it is administered in the form of intramuscular sodium salt.
Fosfomycin: recommended doses
The dose of fosfomycin will depend on the type of infection that the patient presents:
- In those cases where an uncomplicated urinary infection is present, a single dose of 3 g of fosfomycin orally dissolved in liquid is used.
- In the case of gastrointestinal or dermatological infections, the dose is the same as in the previous case.
- To treat acute cystitis in adult women and girls over 12 years of age, 1 sachet of 3 g should be ingested as a single dose.
- If it is necessary to take prophylactically for frequent urinary infections, surgical interventions or a transurethral diagnostic procedure is to be performed, 1 sachet of 3 g should be taken about 3 hours before the intervention or the procedure to be performed. Afterwards, a next dose will be indicated 24 hours after the procedure performed.
- In the case of children over 1 year of age, the dose will be 250 mg to 500 mg in suspension every 8 hours.
- In the elderly, depending on the infection, up to 2 sachets of 3 g can be used with an interval of 24 hours.
2 or 3 days after starting treatment with fosfomycin, clinical symptoms disappear, if they persist, it is not because the treatment is not working, it may be due to the severity of the infectious process.
If the infection is in other places, the treatment will be prolonged and it will be the doctor who is in charge of prescribing the correct dose of fosfomycin, as well as its time of use.
The fosfomycin parenterally is indicated in adults with soft tissue infections of the respiratory tract or genitourinary infections caused by bacteria sensitive to this antibiotic:
- In adults, 1-2 g every 8 hours is indicated. In severe infections, up to 8 g daily may be indicated.
- In children older than 2.5 years, 500 to 1000 mg every 8 hours will be indicated.
- If higher parenteral doses are required, the intravenous route should be used.
- In pregnant women its indication should be given under medical supervision.
Fosfomycin: side effects
The intake of fosfomycin can cause some side effects , not all people are predisposed to suffer them, however, they can be mentioned:
- Headache.
- Runny nose.
- Stomach ache.
- Diarrhea.
- Back pain.
- Vaginal discharge
There are other effects that are rare , but if they appear, they occur in a proportion of 1 in 100 people such as:
- Tingle.
- Fatigue.
- Itching
- Urticaria.
- Abdominal pain.
- Threw up.
In these cases. The ideal is to consult with the doctor, he will verify if it is a side effect and will indicate how it should be treated to avoid complications.
Fosfomycin: contraindications
Fosfomycin is contraindicated in the following cases:
- People who have hypersensitivity to the drug.
- If you have severe kidney failure.
- Patients who are undergoing hemodialysis.
- People allergic to fosfomycin.
- Patients with digestive disorders, such as heartburn, vomiting.
You must bear in mind that the use of fosfomycin should be indicated by a doctor after consultation and an established diagnosis. You should not suspend the treatment without first consulting with your doctor, do not hesitate to go to him if you need it.
This article is merely informative, at FastlyHeal .com we do not have the power to prescribe medical treatments or make any type of diagnosis. We invite you to see a doctor in the case of presenting any type of condition or discomfort.
If you want to read more articles similar to Fosfomycin: what it is, what it is for, dosage and side effects , we recommend that you enter our Medication and medical tests category .

I am a Surgeon with a diploma in comprehensive ultrasound and surgical care residency, an area I am specializing in. During the exercise of my profession, I have realized the need for patients to know the diseases they suffer, and I can tell you that a large part of their complications is due to a lack of information. Being a health web writer allows me to transmit my experience, without borders, to all those readers eager for knowledge, educate them in the prevention of diseases and promote a healthy lifestyle.