Cimetidine is used to treat ulcers; gastroesophageal reflux disease (GERD), a condition in which backward flow of acid from the stomach causes heartburn and injury of the food pipe (esophagus); and conditions where the stomach produces too much acid, such as Zollinger-Ellison syndrome. Over-the-counter cimetidine is used to prevent and treat symptoms of heartburn associated with acid indigestion and sour stomach. Cimetidine is in a class of medications called H2 blockers. It decreases the amount of acid made in the stomach.
Cimetidine comes as a tablet and a liquid to take by mouth. It is usually taken once a day at bedtime or two to four times a day with meals and at bedtime. Over-the-counter cimetidine is usually taken once or twice a day with a glass of water. To prevent symptoms, it is taken within 30 minutes before eating or drinking foods that cause heartburn. Follow the directions on your prescription or the package label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take cimetidine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Do not take over-the-counter cimetidine for longer than 2 weeks unless your doctor tells you to. If symptoms of heartburn, acid indigestion, or sour stomach last longer than 2 weeks, stop taking cimetidine and call your doctor.
Cimetidine is also used sometimes to treat stress ulcers, hives and itching, and viral warts, and to prevent aspiration pneumonia during anesthesia. Talk to your doctor about the possible risks of using this medication for your condition.
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
talk to your doctor about the risks and benefits of taking cimetidine if you are 65 years of age or older. Older adults should not usually take cimetidine because it is not as safe as other medication(s) that can be used to treat the same condition.
Unless your doctor tells you otherwise, continue your normal diet.
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
headache
diarrhea
dizziness
drowsiness
breast enlargement
confusion
excitement
depression
nervousness
seeing things or hearing voices that do not exist (hallucinating)
Cimetidine may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/Safety/MedWatch] or by phone [1-800-332-1088].
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Keep all appointments with your doctor.
Do not let anyone else take your medicine. Ask your pharmacist any questions you have about refilling your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
Last Reviewed - 09/01/2010
AHFS® Consumer Medication Information. © Copyright, 2012. The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.