Skip to content
My WebMD Sign In, Sign Up
Drugs & Medications

Acid Relief (cimetidine)

GENERIC NAME(S): CIMETIDINE

Uses

Cimetidine is used to treat ulcers of the stomach and intestines and prevent them from coming back after they have healed. This medication is also used to treat certain stomach and throat (esophagus) problems caused by too much stomach acid (e.g., Zollinger-Ellison syndrome, erosive esophagitis) or a backward flow of stomach acid into the esophagus (acid reflux disease/GERD). Decreasing extra stomach acid can help relieve symptoms such as stomach pain, heartburn, difficulty swallowing, persistent cough, and trouble sleeping. It can also prevent serious acid damage to your digestive system (e.g., ulcers, cancer of the esophagus).

Cimetidine belongs to a class of drugs commonly called H2 blockers. It works by reducing the amount of acid in your stomach.

This medication is also available without a prescription. It is used to treat occasional heartburn caused by too much acid in the stomach (also called acid indigestion or sour stomach). It is also used to prevent heartburn and acid indigestion caused by certain foods and beverages. If you are taking this medication for self-treatment, it is important to read the manufacturer's package instructions carefully so you know when to consult your doctor or pharmacist. (See also Precautions.)

How to use Acid Relief (cimetidine)

Take this medication by mouth with or without food as directed by your doctor.

The dosage and length of treatment are based on your medical condition and response to therapy. Follow your doctor's instructions carefully. If you are also taking antacids to relieve stomach pain as recommended by your doctor, separate them from this medication by at least 1 hour.

Take this medication regularly as prescribed in order to get the most benefit from it. To help you remember, take it at the same time(s) each day. Do not increase your dose or take it more often than directed. Continue to take this medication for the prescribed length of treatment even if you are feeling better. Stopping treatment too early may delay the healing process.

If you are using nonprescription cimetidine for self-treatment of acid indigestion or heartburn, take 1 tablet by mouth with a glass of water as needed. To prevent heartburn, take 1 tablet by mouth with a glass of water right before or up to 30 minutes before eating food or drinking beverages that cause heartburn. Do not take more than 2 tablets in 24 hours unless directed by your doctor. Do not take for more than 14 days in a row without talking with your doctor.

Inform your doctor if your symptoms do not improve or if they worsen.

Side Effects

Headache, dizziness, drowsiness, or diarrhea may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

If your doctor has directed you to use this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor immediately if any of these unlikely but serious side effects occur: mental/mood changes (e.g., agitation, confusion, depression, hallucinations), trouble urinating, muscle/joint pain, breast swelling/soreness in males, decreased sexual ability (with very high doses of this medication).

Tell your doctor immediately if any of these rare but very serious side effects occur: easy bruising/bleeding, signs of infection (e.g., fever, persistent sore throat, cough, trouble breathing), fast/slow/irregular heartbeat, unusual tiredness, persistent nausea/vomiting, severe stomach/abdominal pain, dark urine, yellowing eyes/skin, change in the amount of urine.

A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking cimetidine, tell your doctor or pharmacist if you are allergic to it; or to other H2 blockers (e.g., famotidine, nizatidine, ranitidine); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: immune system problems, kidney problems, liver problems, certain lung diseases (chronic obstructive pulmonary disease-COPD), diabetes, other stomach problems (e.g., tumors).

Some symptoms may actually be signs of a more serious condition. Get medical help right away if you have: heartburn with lightheadedness/sweating/dizziness, chest/jaw/arm/shoulder pain (especially with shortness of breath, unusual sweating), unexplained weight loss.

In addition, before you self-treat with this medication, get medical help right away if you have any of these signs of a serious condition: trouble/pain swallowing food, bloody vomit, vomit that looks like coffee grounds, bloody/black stools, heartburn for over 3 months, frequent chest pain, frequent wheezing (especially with heartburn), nausea/vomiting, stomach pain.

This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.

Do not use this medication to treat children younger than 12 unless directed by the doctor.

Older adults may be more sensitive to the side effects of this drug, especially confusion and lung infection (pneumonia). Confusion can increase the risk of falling.

Cimetidine should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.

Cimetidine passes into breast milk. Consult your doctor before breast-feeding.

Interactions

See also How to Use section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include: cisapride, dofetilide, epirubicin, ticlopidine, artemether, clopidogrel, carmustine, lumefantrine, metformin, moclobemide, moricizine, procainamide, quinidine, silver sulfadiazine.

This medication can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include lidocaine, metoprolol, propranolol, tacrine, warfarin, zaleplon, anti-seizure drugs (such as carbamazepine, phenytoin), benzodiazepines (such as diazepam), calcium channel blockers (such as diltiazem), narcotic analgesics (such as codeine), tricyclic antidepressants (such as amitriptyline), theophylline, among others.

Since cimetidine reduces the amount of acid in your stomach, it may also change the absorption of certain medications and affect how they work. Some examples of affected drugs include atazanavir, dasatinib, delavirdine, certain azole antifungals (such as itraconazole, ketoconazole), pazopanib, among others. Ask your doctor or pharmacist if any of the medications you take are affected by cimetidine and how to manage this interaction.

Check the labels on all your medicines because they may contain nonsteroidal anti-inflammatory drugs (NSAIDs such as aspirin, ibuprofen, naproxen) that may cause stomach irritation/ulcers. Ask your pharmacist about the safe use of those products. Low-dose aspirin should be continued if prescribed by your doctor for specific medical reasons such as heart attack or stroke prevention (usually at dosages of 81-325 milligrams per day). Consult your doctor or pharmacist for more details.

Cigarette smoking can affect this medication. Tell your doctor if you smoke and if you stop or start smoking while using this medication.

This medication and similar H2 blockers (such as famotidine, nizatidine, ranitidine) are available both with and without a prescription. Do not take them at the same time.

Overdose

If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include mental/mood changes, slurred speech, difficulty awakening.

Notes

Do not share this medication with others.

Lifestyle changes such as stress reduction programs, stopping smoking, limiting alcohol, and diet changes (e.g., avoiding caffeine and spicy foods) may increase the effectiveness of this medication. Talk to your doctor or pharmacist about lifestyle changes that might benefit you.

Laboratory and/or medical tests may be performed to monitor your progress or check for side effects. Consult your doctor for more details.

Missed Dose

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

Storage

Store in a tightly closed container at room temperature between 59-86 degrees F (15-30 degrees C) away from moisture and light. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised June 2014. Copyright(c) 2014 First Databank, Inc.

Images

CIMETIDINE 300 MG TABLET
CIMETIDINE 300 MG TABLET
View Larger Picture
color
No data.
shape
No data.
imprint
No data.
CIMETIDINE 400 MG TABLET
CIMETIDINE 400 MG TABLET
View Larger Picture
color
No data.
shape
No data.
imprint
No data.
CIMETIDINE 800 MG TABLET
CIMETIDINE 800 MG TABLET
View Larger Picture
color
No data.
shape
No data.
imprint
No data.
CIMETIDINE 300 MG TABLET
CIMETIDINE 300 MG TABLET

Identification

color
No data.
shape
No data.
imprint
No data.
This medicine is a dark green, oval, film-coated tablet imprinted with "N192" and "300".
CIMETIDINE 400 MG TABLET
CIMETIDINE 400 MG TABLET

Identification

color
No data.
shape
No data.
imprint
No data.
This medicine is a dark green, oval, scored, film-coated tablet imprinted with "N 204" and "400".
CIMETIDINE 800 MG TABLET
CIMETIDINE 800 MG TABLET

Identification

color
No data.
shape
No data.
imprint
No data.
This medicine is a white, oval, scored, film-coated tablet imprinted with "N 305" and "800".

Add to Cabinet

Add Adderall to my medicine cabinet.

Did you know?

With WebMD's Medicine Cabinet, you can check interactions with drugs.

Go to medicine cabinet

Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

More about Drugs and Medications

Newsletters

Subscribe to free WebMD newsletters.

  • WebMD Daily

    WebMD Daily

    Subscribe to the WebMD Daily, and you'll get today's top health news and trending topics, and the latest and best information from WebMD.

  • Men's Health

    Men's Health

    Subscribe to the Men's Health newsletter for the latest on disease prevention, fitness, sex, nutrition, and more from WebMD.

  • Women's Health

    Women's Health

    Subscribe to the Women's Health newsletter for the latest on disease prevention, fitness, sex, diet, anti-aging, and more from WebMD.

By clicking Submit, I agree to the WebMD Terms & Conditions & Privacy Policy

URAC: Accredited Health Web Site TRUSTe online privacy certification HONcode Seal AdChoices