Fosfomycin 3gm sachet starts working to kill bacteria within hours after you take it. However, you may not notice a significant improvement in your symptoms immediately. Here's a breakdown of the timeframe:

Starts Working: Fosfomycin begins killing bacteria within hours of taking the single-dose sachet.

Symptoms Improve: It typically takes 2-3 days for symptoms of a urinary tract infection (UTI) to improve noticeably after taking fosfomycin.

Important Note:

Even though you may feel better after a few days, it's crucial to finish the entire course of antibiotics, which is usually just the single dose for fosfomycin in the case of UTIs. This ensures all bacteria are eliminated to prevent recurrence of the infection.