Fonyl is a broad-spectrum antibiotic which kills the infection causing bacteria in your body by affecting and damaging the cell wall (covering of bacteria) synthesis. It is also seen that Fonyl prevents the attachment of bacteria to superficial cells of urinary bladder, hence preventing infection.

The time for which Fonyl will stay in our body depends upon how well your kidney functions as this medicine is excreted by the kidney. In healthy adults, about 80-90% of the total medicine injected is excreted by kidney within 10 hours after a single injection into the veins. If the patient has kidney dysfunction, the medicine may stay back for a longer time in the body.

This medication is an antibiotic used in few specific conditions like infections of urinary bladder infections and lower urinary tract infections and the infection of bone marrow. It is also sometimes used to treat infection of meninges (covering of the brain). Whether this medicine should be given to you or not will be decided by your doctor depending upon the type of bacteria causing the infection. It acts only in bacterial infections and is of no use in viral infections (such as common cold and flu).

The schedule of taking Fonyl is decided by your doctor. The daily dose is determined on the basis of bacteria causing the infection, severity and site of the infection. While deciding the dose and duration, the doctor will also consider your age, body weight and status of kidney function. Usually, it is given as 2–3 divided doses in whole day.

Fonyl should be given with caution if the patient has kidney problems. Your doctor may get regular blood tests done to monitor kidney function. If at all needed to be given to patients with kidney impairment, the doctor may need to adjust the dose according to the severity of the kidney problem.