Fosmol: A Single Dose Drug Against UTI and Others

Non-adherence to treatment regimen is a great concern to many players in the health industry. Especially in the case of antimicrobials, it may lead to antimicrobial resistance or make common or life-threatening infections more difficult or sometimes impossible to treat.

Most often people discontinue their antibiotic therapy when they look or feel healthy or when they experience a side effect. That is why a shorter duration regimen may be ideal for improving medication adherence.

Fosmol

Fosmol is a product of Labiana Pharmaceuticals S.L.U, a pharmaceutical company based in Barcelona, Spain, but marketed by Pharma Bavaria International. The active ingredient in Fosmol is Fosfomycin trometamol, a a novel class of antibacterial drugs with a chemical structure unrelated to other known antibiotics. It is a bactericidal drug that disrupts cell wall synthesis by inhibiting phosphoenolpyruvate synthetase and thus interferes with the production of peptidoglycan.

The medication is indicated for the treatment of acute uncomplicated lower urinary tract infections in adults, caused by pathogens sensitive to Fosfomycin trometamol. It is also indicated for periprocedural prophylaxis in diagnostic and surgical transurethral procedures. The recommended dose is one sachet of Fosmol 3g in a single daily administration. When used as periprocedural prophylaxis, a repeat dose may be given after the procedure.

Fosmol is a prescription only drug, thus cannot be bought without a written instruction from a medical practitioner. It is available in pharmacies here in Ghana. The medication is generally well tolerated, with gastrointestinal adverse events (such as diarrhoea, nausea) reported most commonly. However, there might be other side effects too.

What Studies Say

Fosfomycin trometamol has good in vitro activity against common uropathogens, such as Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae and Staphylococcus saprophyticus. Also, a single-dose Fosfomycin trometamol had similar clinical and/or bacteriological efficacy to 3- to 7-day regimens of ciprofloxacin, norfloxacin, cotrimoxazole or nitrofurantoin in women with uncomplicated lower UTIs. Its efficacy in pregnant women with asymptomatic bacteriuria is similar to that of cefuroxime axetil and amoxicillin/clavulanic acid. Also in pregnant women with lower UTI, Fosfomycin trometamol’s efficacy was similar to that of cefuroxime axetil, amoxicillin/clavulanic acid and ceftibuten. (Keating 2013)

Considering the convenience of taking a single dose, Van Pienbroek, Hermans, Kaptein & Mulder (1993) concluded in their study that Fosfomycin trometamol is a reasonable alternative to 7 days nitrofurantoin 50 mg four times a day in the treatment of women with symptoms of acute uncomplicated urinary tract infections in general practice.

Nursing Consideration

• Fosmol is available as a powder formulation which can be dissolved in liquid and taken orally. The content must be mixed with half glass of water (about 120mls) before taking. Do not use warm or hot water.
• The drug should be taken on an empty stomach, either 1 hour before or at least 2 hours after meals and preferably before bedtime after emptying the bladder.
• Symptoms of the disease should get better within 2 to 3 days. However, it is important to report back to the doctor if symptoms persist after 3 days or condition get worse.
• In the event of overdose, it is enough to increase urinary elimination of drug substance by oral liquids administration.
• One may experience side effects such as dizziness which may affect the ability to drive or use machines
• Fosmol contains sucrose, thus patients with rare hereditary problems of fructose intolerance, glucose – galactose malabsorption or sucrase-isomaltase insufficiency should not take this medicine.
• Concomitant administration of metoclopramide has been shown to lower serum and urinary concentrations and should be avoided
• The medication is contraindicated in patients with severe renal insufficiency (CLcr<10ml/min) and patients undergoing haemodialysis

Disclaimer: This write-up is for informational purposes only and does not in any way suggest the author endorses (or invalidate) the medication. Also, the content of this article and the entire website is for informational purposes only and should not be taken as professional medical advice.

Reference

Fosfomycin 3 g granules for oral solution – Summary of Product Characteristics (SmPC) – (emc). (n.d.). Electronic Medicines Compendium. Retrieved April 10, 2021, from https://www.medicines.org.uk/emc/product/7219/smpc#gref

Fosfomycin Tromethamine Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing – WebMD. (n.d.). Web MD. Retrieved April 10, 2021, from https://www.webmd.com/drugs/2/drug-297/fosfomycin-tromethamine-oral/details

Ingersoll, K. S., & Cohen, J. (2008). The impact of medication regimen factors on adherence to chronic treatment: a review of literature. Journal of behavioral medicine, 31(3), 213–224. https://doi.org/10.1007/s10865-007-9147-y

Keating G. M. (2013). Fosfomycin trometamol: a review of its use as a single-dose oral treatment for patients with acute lower urinary tract infections and pregnant women with asymptomatic bacteriuria. Drugs, 73(17), 1951–1966. https://doi.org/10.1007/s40265-013-0143-y

Labiana Life Sciences S.A. (2018, November 13). Fosfomicina Labiana 3 g 1 sachet ». LABIANA Group. https://www.labiana.com/en/human-medicine/fosfomicina-labiana-3-g-1-sachet/

(2020, December 22). Corporate. Pharma Bavaria International. https://pharma-bavaria.com/corporate/

MSD Manuals. (n.d.). Fosfomycin. MSD Manual Professional Edition. Retrieved April 10, 2021, from https://www.msdmanuals.com/professional/infectious-diseases/bacteria-and-antibacterial-drugs/fosfomycin#:%7E:text=Fosfomycin%20is%20a%20novel%20class,with%20the%20production%20of%20peptidoglycan.

Van Pienbroek, E., Hermans, J., Kaptein, A. A., & Mulder, J. D. (1993). Fosfomycin trometamol in a single dose versus seven days nitrofurantoin in the treatment of acute uncomplicated urinary tract infections in women. Pharmacy world & science : PWS, 15(6), 257–262. https://doi.org/10.1007/BF01871127