Fosfocors sachet is an antibiotic medication used to treat urinary tract infections by killing bacteria. It should be taken regularly at prescribed intervals, with the dose varying based on the condition. Common side effects include headache, diarrhea, dizziness, vaginal inflammation, and indigestion. Consult a doctor if symptoms persist or worsen. Avoid alcohol and caffeine, as they may cause sleepiness and dizziness. Pregnant or breastfeeding mothers should consult their doctor.