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Oyster Shell

Generic name: calcium carbonateKAL-see-um-KAR-boe-nate ]
Brand names: Alka-Mints, Alka-Seltzer Cool Action Heartburn Relief, Alka-Seltzer Extra Strength Heartburn Relief, Calcium Oyster Shell, Cal-Gest, ... show all 21 brands
Drug classes: Antacids, Minerals and electrolytes

Medically reviewed by Drugs.com on Aug 1, 2023. Written by Cerner Multum.

What is Oyster Shell?

Calcium is a mineral that is found naturally in foods. Calcium is necessary for many normal functions of the body, especially bone formation and maintenance.

Oyster Shell is used to prevent or to treat a calcium deficiency.

There are many brands and forms of calcium carbonate available. Not all brands are listed on this leaflet.

Oyster Shell may also be used for purposes not listed in this medication guide.

Oyster Shell side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Oyster Shell may cause serious side effects. Call your doctor at once if you have:

Common side effects of Oyster Shell may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Warnings

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Before taking this medicine

Ask a doctor or pharmacist if it is safe for you to take Oyster Shell if you have ever had:

Ask a doctor before using Oyster Shell if you are pregnant or breast-feeding. Your dose needs may be different during pregnancy or while you are nursing.

How should I take Oyster Shell?

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Check the label of your Oyster Shell product to see if it should be taken with or without food.

Swallow the Oyster Shell regular tablet with a full glass of water.

The chewable tablet should be chewed before you swallow it.

Shake the oral suspension (liquid) well just before you measure a dose. Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

Use the Oyster Shell powder as directed. Allow the powder to dissolve completely, then consume the mixture.

Oyster Shell may be only part of a complete program of treatment that also includes dietary changes. Learn about the foods that contain calcium.

Your Oyster Shell dose may need to be adjusted as you make changes to your diet. Follow your doctor's instructions very closely.

Store at room temperature away from moisture and heat. Do not freeze.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Oyster Shell?

Ask a doctor or pharmacist before taking any multivitamins, mineral supplements, or antacids while you are taking Oyster Shell.

What other drugs can affect Oyster Shell?

Calcium can make it harder for your body to absorb certain medicines. If you take other medications, take them at least 2 hours before or 4 or 6 hours after you take Oyster Shell.

Other drugs may interact with calcium carbonate, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Does Oyster Shell interact with my other drugs?

Enter medications to view a detailed interaction report using our Drug Interaction Checker.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.