FONYL 4GM Injection is an antibiotic medicine used to treat bacterial infections in your body. It is effective in some infections of the urinary tract, lungs (eg. pneumonia), bones, brain (eg. meningitis), and blood. However, it is only used when other common antibiotics cannot be used.Fonyl Injection kills bacteria, which helps to improve your symptoms and cure the infection. It is given as a drip (intravenous infusion) into a vein under the supervision of a healthcare professional. Your doctor will decide the correct dose for you. You should use this medicine regularly at evenly spaced intervals as per the schedule prescribed by your doctor. Do not skip any doses and finish the full course of treatment even if you feel better. Stopping the medicine too early may lead to the infection returning or worsening.The most common side effects of this medicine include injection site reactions (pain, swelling, or redness), vaginal inflammation, and stomach pain. Some people may develop temporary redness or pain at the site of injection. These side effects are usually mild but let your doctor know if they bother you or last more than a few days.Before using it, you should tell your doctor if you are allergic to any antibiotics or have any liver or kidney problems. Pregnant and breastfeeding mothers should consult their doctor before using it. This medicine may make you feel sleepy and dizzy. Do not drive if these symptoms occur.