What is this medication?
CIMETIDINE (sye MET i deen) treats heartburn, stomach ulcers, reflux disease, or other conditions that cause too much stomach acid. It works by reducing the amount of acid in the stomach.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Acid Reducer, Major Acid Reducer, Tagamet, Tagamet HB
What should I tell my care team before I take this medication?
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 medications, foods, dyes, or preservatives
- Pregnant or trying to get pregnant
How should I use this medication?
Take this medication by mouth. Follow the directions on the prescription label. Swallow the tablets with a drink of water. If you only take this medication once a day, take it at bedtime. Take your doses at regular intervals. Do not take your medication more often than directed.
Talk to your care team regarding the use of this medication in children. Special care may be needed.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
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 medication?
Do not take this medication with any of the following:
This medication may also interact with the following:
- Female hormones, including contraceptive or birth control pills
- Medications for heart rhythm problems
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medication?
Tell your care team if your pain does not start to get better or gets worse. You may need to take this medication for several days before your symptoms get better. Finish the full course of tablets prescribed even if you feel better.
Do not take with aspirin, ibuprofen, or other antiinflammatory medications unless directed to do so by your care team. 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 care team right away. You may have a bleeding ulcer.
This medication may cause a decrease in vitamin B12. Make sure that you get enough vitamin B12 while you are taking this medication. Discuss the foods you eat and the vitamins you take with your care team.
What side effects may I notice from receiving this medication?
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
- Breast swelling, tenderness
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medication?
Keep out of the reach of children.
Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from light. Keep container tightly closed. Throw away any unused medication after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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