Calcium and magnesium are naturally occurring minerals. Calcium is needed for bone formation and maintenance. Magnesium helps maintain muscle function and normal heart rhythm.

Calcium carbonate and magnesium chloride is a combination medicine used as a supplement. This medicine is given when your diet does not provide enough of these minerals, or when they are lost through perspiration.

Calcium carbonate and magnesium chloride may also be used for purposes not listed in this medication guide.

You should not use this medicine if you have ever had an allergic reaction to an antacid or vitamin/mineral supplement that contains calcium carbonate or magnesium chloride.

Ask a doctor or pharmacist if this medicine is safe to use if you have:

• kidney disease;
• a history of kidney stones;
• heart disease; or
• a blockage in your intestines.

Ask a doctor before using this medicine if you are pregnant or breastfeeding. Your dose needs may be different during pregnancy or while you are nursing.

Use Slow Magnesium Chloride With Calcium (Oral) 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.

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

Stop using calcium carbonate and magnesium chloride and call your doctor at once if you have:

• nausea, vomiting, stomach pain, loss of appetite, increased thirst or urination;
• muscle pain or weakness, joint pain;
• confusion, feeling tired or restless; or
• slow heart rate, drowsiness, feeling light-headed.

Common side effects may include:

• diarrhea;
• constipation; or
• upset stomach.

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.

Avoid taking other medicines at the same time you take calcium carbonate and magnesium chloride.