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Date of last update: 10/17/2017.

Forum Name: Endocrinology Topics

Question: Does Synthroid itself cause hair loss?

 Hwdintersection - Mon Sep 29, 2008 10:02 am


I started losing my hair after I started on Synthroid. I am hypothyroid. I took Cytomel for a year previous to Synthroid. I am now on 75 mg of Synthroid and have some hair loss daily.

The package insert for Synthroid says it causes hair loss. I have spoken to my endocrinologist 2 times about this and she says that the package inserts have to put any symptoms people could have on the medication but that Synthroid does NOT cause hair loss.

I am also vitamin B deficient and am wondering perhaps this is the culprit. I am now on sublingual B-12.

Please help! Thank you.
 Debbie Miller, RN - Tue Sep 30, 2008 11:30 am

User avatar Hello,
Your doctor is right that synthroid does not cause hair loss and that the package insert does have to list every reported symptom (whether or not it was caused by the drug).

The reason someone would experience the loss is because of the delayed response of hair growth to the hypothyroid condition. Hair grows very slowly and so loss continues for perhaps six months after the thyroid hormone is replaced.

The B vitamins as well as vitamin A, C, and Biotin can sometimes also affect hair so it's good to have a good supplement when experiencing hair growth concerns.

Best wishes.

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