Jun 16 2003
The drug, raloxifene -- also known by its brand name, Evista -- can interfere with proper absorption of thyroid hormone when both drugs are taken at the same time. This information was released in a study published in the June 9, 2003 issue of the Archives of Internal Medicine.According to the researchers, raloxifene -- a popular treatment for osteoporosis -- may be being taken by as many as 2.5 million women who also take thyroid medications, making those thyroid medications less effective. When the thyroid medicines are not abosbed properly, the women are at higher risk of becoming increasingly hypothyroid and symptomatic.
What You Should Do?
If you are a woman who is on thyroid hormone replacement drugs (Synthroid, Unithroid, Levoxyl, Levothroid, levothyroxine, Thyrolar, Armour, etc.) and you are prescribed Raloxifene, you need to have your thyroid levels rechecked within approximately 12 weeks.
And you are are a woman who takes raloxifene and you are diagnosed with a thyroid problem, be sure to have your thyroid levels checked frequently to ensure that your dosage is adjusted properly to account for the impact of your raloxifene.
To ensure that you have the least amount of interference, rather than take them at the same time, consider taking your thyroid hormone first thing in the morning, and the raloxifene 12 hours later.
While the manufacturer of Evista told Reuters Health that the report "is a case study of a single patient and does not provide substantial evidence of raloxifene causing malabsorption of (thyroid hormone)," thyroid patients should still ask doctors for retesting after starting raloxifene.
Source: Elias S. Siraj, MD; Manjula K. Gupta, PhD; S. Sethu K. Reddy, MD. "Raloxifene Causing Malabsorption of Levothyroxine," Arch Intern Med. 2003;163:1367-1370.
