What medications can cause high calcium levels?

The most common medications that have been associated with increased blood calcium levels (also called hypercalcemia) include:

• Lithium
• Thiazide diuretics
• Teriparatide
• Estrogens
• Tamoxifen.

Calcium and vitamins A or D when taken in excess may also raise blood calcium levels.

Increased calcium levels may not cause any symptoms. Usually, the only thing necessary to correct the high calcium levels caused by medications is to stop the medicine or reduce its dose.

Calcium plays a very important role in the human body. It is a main component in your bones, and it is involved in muscle contractions, including those of your heart. The levels of calcium in your body are regulated through a complex coordination between your digestive tract, your bones, your kidneys and your parathyroid gland.

Increased calcium in your blood can occur in one of three ways:

• Increased absorption from your intestines
• Decreased excretion through your kidneys
• Mineral discharge from your bones.

Medications are not a common cause of increased calcium levels. Most hypercalcemia caused by medications is not severe and may not cause any symptoms. It may be discovered when routine labs are obtained for another reason. The higher the calcium level rises, the more likely symptoms are to occur. Possible symptoms include:

• Decreased appetite
• Nausea
• Vomiting
• Constipation
• Confusion
• Increased thirst
• Increased urination.