What is this medicine?
CIMETIDINE (sye MET i deen) is a type of antihistamine that blocks the release of stomach acid. It is used to treat stomach or intestinal ulcers. It can relieve ulcer pain and discomfort, and the heartburn from acid reflux.
What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
- blood in your stools (black or tarry stools) or if you have blood in your vomit
- kidney disease
- liver disease
- pain or trouble trying to swallow food
- an unusual or allergic reaction to cimetidine, other medicines, foods, dyes, or preservatives
- pregnant or trying to get pregnant
How should I use this medicine?
Take this medicine by mouth. Follow the directions on the prescription label. Shake well before using. Use a specially marked spoon or container to measure your medicine. Ask your pharmacist if you do not have one. Household spoons are not accurate. If you only take this medicine once a day take it at bedtime. Take your doses at regular intervals. Do not take your medicine more often than directed.
Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
What may interact with this medicine?
Do not take cimetidine if you take the following drugs:
This medicine may also interact with the following medications:
- female hormones, including contraceptive or birth control pills
- medicines for heart rhythm problems
What should I watch for while using this medicine?
Tell your doctor or health care professional if your pain does not start to get better or gets worse. You may need to take this medicine for several days before your symptoms get better. Finish the full course of medicine prescribed by your doctor or health care professional even if you feel better.
Do not take with aspirin, ibuprofen, or other antiinflammatory medicines unless directed to do so by your health care professional. These can make your condition worse.
Do not smoke cigarettes or drink alcohol. These increase irritation in your stomach and can increase the time it will take for your ulcer to heal.
If you get black, tarry stools or vomit up what looks like coffee grounds, call your doctor or health care professional right away. You may have a bleeding ulcer.
If you need to take an antacid you should take it at least 1 hour before or 1 hour after cimetidine. This medicine will not work as well if taken at the same time as an antacid.
What side effects may I notice from receiving this medicine?
Side effects that you should report to your doctor or health care professional as soon as possible:
- allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
- agitation, nervousness, depression, hallucinations
- breast swelling, tenderness
- change in sex drive or performance
- dark urine
- redness, blistering, peeling or loosening of the skin, including inside the mouth
- yellowing of the eyes or skin
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
- nausea, vomiting