Brand Name(s):

  • Alka-Seltzer®Heartburn

Other Name(s):

  • baking soda
  • citrocarbonate

WHY is this medicine prescribed?

Sodium bicarbonate is an antacid used to relieve heartburn and acid indigestion. Your doctor also may prescribe sodium bicarbonate to make your blood or urine less acidic in certain conditions.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

HOW should this medicine be used?

Sodium bicarbonate comes as a tablet and powder to take by mouth. Sodium bicarbonate is taken one to four times a day, depending on the reason you take it. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take sodium bicarbonate exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

If you are using sodium bicarbonate as an antacid, it should be taken 1 to 2 hours after meals, with a full glass of water. If you are using sodium bicarbonate for another reason, it may be taken with or without food. Do not take sodium bicarbonate on an overly full stomach.

Dissolve sodium bicarbonate powder in at least 4 ounces (120 milliliters) of water. Measure powdered doses carefully using a measuring spoon.

Do not use sodium bicarbonate for longer than 2 weeks unless your doctor tells you to. If sodium bicarbonate does not improve your symptoms, call your doctor.

Do not give sodium bicarbonate to children under 12 years of age unless your doctor tells you to.

What SPECIAL PRECAUTIONS should I follow?

Before taking sodium bicarbonate,

  • tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially other antacids, aspirin or aspirin-like medicines, benzodiazepines, flecainide (Tambocor), iron, ketoconazole (Nizoral), lithium (Eskalith, Lithobid), methenamine (Hiprex, Urex), methotrexate, quinidine, sulfa-containing antibiotics, tetracycline (Sumycin), or vitamins. Take sodium bicarbonate at least 2 hours apart from other medicines.
  • tell your doctor if you have or have ever had high blood pressure, congestive heart failure, or kidney disease or if you have recently had bleeding in your stomach or intestine.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking sodium bicarbonate, call your doctor.

What SPECIAL DIETARY instructions should I follow?

This medicine increases the amount of sodium in your body. If you are on a sodium-restricted diet, check with your doctor before taking sodium bicarbonate.

What should I do IF I FORGET to take a dose?

If your doctor has told you to take sodium bicarbonate on a certain schedule, 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.

What SIDE EFFECTS can this medicine cause?

Sodium bicarbonate may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • increased thirst
  • stomach cramps
  • gas

If you have any of the following symptoms, stop taking sodium bicarbonate and call your doctor immediately:

  • severe headache
  • nausea
  • vomit that resembles coffee grounds
  • loss of appetite
  • irritability
  • weakness
  • frequent urge to urinate
  • slow breathing
  • swelling of feet or lower legs
  • bloody, black, or tarry stools
  • blood in your urine

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 Web Site] or by phone [1-800-332-1088].

What should I know about STORAGE and DISPOSAL of this medication?

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.

What should I do in case of OVERDOSE?

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.

What OTHER INFORMATION should I know?

If your doctor has prescribed sodium bicarbonate, keep all scheduled appointments so that your response to the medicine can be checked.

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.

AHFS® Consumer Medication Information. © Copyright, 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.

Last Reviewed: February 1, 2009.