Hi, Welcome to Healthcare Magic Forum. I have gone through your Query & I really appreciate your concern about the problem you are facing. As a physician i would like to tell you that Famotidine a histamine-2 blockers. Famotidine works by decreasing the amount of acid the stomach produces. Famotidine is used to treat and prevent ulcers in the stomach and intestines. It also treats conditions in which the stomach produces too much acid, such as Zollinger-Ellison syndrome, GERD and other conditions in which acid backs up from the stomach into the esophagus, causing heartburn. I woul also like to tell you that there are not sufficient studies to prove it s dire side effects in prolonged use. But I urge to you to keep an eye out for following side effects and contact your doctor as soon as you think anything is wrong Stop using famotidine and call your doctor at once if you have: fast or pounding heartbeats with severe dizziness; or unexplained muscle pain, tenderness, or weakness especially if you also have fever, unusual tiredness, and dark colored urine. Common famotidine side effects may include: headache; dizziness; or constipation or diarrhea. Thanks for Trusting & Posting your Query on this forum. Hope this will help you. Feel free to ask any further question. Have a nice Day. Regards, Dr.Abhijeet