Question:

The printout that came with my levothyroxine states not to take calcium within 4 hrs of taking it. I normally have orange juice with calcium for breakfast, take a 600 mg. calcium pill with lunch and dinner. This made taking the levothyroxine difficult. I began taking the levothyroxine around 3 or 4 AM to avoid the interaction.

Does this sound alright to do? Is there a better way.  OR is this not necessary to worry about at all???

ANOTHER PART OF THE QUESTION IS: I take the 70 mg. Fosamax once a week. Is it OK that I am taking the thyroid pill approximately 4 hours. before I take the Fosamax.  (Fosamax should be taken on an empty stomach)

Answer:

Calcium interferes with the absorption of many medicines. Its interaction levothyroxine can result in reduced levels of the medicine and the potential for recurrence of symptoms related to reduced thyroid function. The source of the calcium does not seem to be important. There is some literature to recommend waiting 4 hours between taking the levothyroxine and the calcium.

Another name for Fosamax is alendronate. Alendronate is one of several medicines known as bisphosphonates that are mainly used to reduce bone loss in older adults. The bisphosphonates as a class are poorly absorbed under the best conditions. It is important to take them on an empty stomach. The literature from the company marketing alendronate states that nothing but the plain water needed to rinse the tablet down should be taken for at least 30 minutes after the each dose. While literature documenting an interaction between alendronate and calcium is lacking, it is likely an interaction exists.

All of this concern about drug interactions may obscure the issue of compliance or adherence to prescribed drug therapy. In short, the best way to achieve the goals of drug therapy is to take the medicines regularly, just the way your doctor has recommended. Dosing regimens that require patients to disrupt normal behavior patterns are likely to fail due to poor compliance. Getting up in the middle of the night to take a medicine seems to be a prime example of this sort of regimen. We would not recommend continuing this practice. It might reduce the likelihood of a drug interaction, but it is unnecessarily disruptive.

It makes sense to take the alendronate first thing in the morning, followed by the levothyroxine a little later (at least 30 minutes after the alendronate). Skip the AM juice with calcium entirely or get a juice that does not contain calcium and take it when you take your levothyroxine. Take your calcium supplements at least 4 hours after the levothyroxine. You might be able to take the calcium fortified juice later in the day if it’s really important to you. Ask your doctor if you have further questions about your medicines.

For more information:

Go to the Pharmacy and Medications health topic.