Ranitidine is known as an H2 histamine blocker. It works by reducing the amount of acid in your stomach. It is used to prevent and treat heartburn and other symptoms caused by too much acid in the stomach (acid indigestion).

To treat heartburn and acid indigestion, take 1 tablet with a glass of water as needed, unless otherwise directed by your doctor. Swallow the tablet whole without chewing. Ranitidine can be taken with or without food.

To prevent heartburn and acid indigestion, take ranitidine 30-60 minutes before eating food or drinking beverages that can cause indigestion.

Do not take more than 2 tablets in 24 hours unless directed by your doctor. Follow all directions on the product package. If you are uncertain about any of the information, consult your doctor or pharmacist.

Stop taking this medication and call your doctor promptly if your symptoms continue after you begin taking it, or if they do not improve after you have been taking this medication for 14 days in a row. Do not take this medication for more than 14 days in a row without talking with your doctor.

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

Tell your doctor immediately if you have any of these rare but very serious side effects: vomiting, severe stomach pain, dark urine, yellowing eyes/skin.

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.

Before taking ranitidine, tell your doctor or pharmacist if you are allergic to it; or to other acid blockers (e.g., cimetidine, famotidine); 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.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: a certain blood disorder (porphyria), kidney problems, liver problems, other stomach problems (e.g., tumors).

Some symptoms may actually be signs of a more serious condition. Tell your doctor immediately if you have: chest pain or shoulder/jaw pain (especially with trouble breathing), heartburn combined with lightheadedness/sweating/dizziness, heartburn for longer than 3 months, nausea/vomiting, pain spreading to arms/neck/shoulders, persistent stomach pain, black stools, difficult/painful swallowing, unexplained weight loss, vomit that is bloody or looks like coffee grounds.

This drug may make you dizzy. 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 in children younger than 12 unless directed by the doctor.

During pregnancy, this medication should only be used if clearly needed. Discuss the risks and benefits with your doctor. Tell your doctor if you are pregnant before using this medication.

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

The effects of some drugs can change if you take other drugs or herbal products at the same time. This can increase your risk for serious side effects or may cause your medications not to work correctly. These drug interactions are possible, but do not always occur. Your doctor or pharmacist can often prevent or manage interactions by changing how you use your medications or by close monitoring.

To help your doctor and pharmacist give you the best care, be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products) before starting treatment with this product. While using this product, do not start, stop, or change the dosage of any other medicines you are using without your doctor's approval.

Some products that may interact with this drug include: procainamide, propantheline.

This medication decreases the amount of acid in your stomach. This can change the amount of medication absorbed from your stomach which may affect how these medications work. Examples of affected drugs include atazanavir, delavirdine, dasatinib, gefitinib, raltegravir, triazolam among others. Azole antifungals such as ketoconazole may also be affected.

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

This medication and similar acid blockers (e.g., cimetidine, famotidine) are available both over-the-counter and by prescription. Do not take them at the same time.

Ranitidine may interfere with certain laboratory tests (e.g., urine protein), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

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.

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

Not applicable.

Store between 36-77 degrees F (2-25 degrees C) away from light and moisture. 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 March 2013. Copyright(c) 2013 First Databank, Inc.