Levothyroxine/Oral Calcium Acetate; Carbonate; Citrate Interactions

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

Calcium acetate, calcium carbonate, and calcium citrate decreases the amount of levothyroxine your body absorbs.

What might happen:

Your levothyroxine may not work as well. Signs and symptoms to look for include: feeling tired, dry skin and brittle nails, not being able to stand the cold, constipation, and depression.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. Your doctor may want to check you thyroid function test to see if you are getting the right amount of levothyroxine. Your doctor may want you to take your levothyroxine and calcium at different times of the day.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.

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