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Date of last update: 10/17/2017.

Forum Name: Endocrinology Topics

Question: Synthroid and Phentermine or Hoodia

 StephieT11SN - Wed Jan 03, 2007 4:39 pm

I'm a 33 yof with Hypothyroidism S/P sub-total thyroidectomy in May 2006 for a goiter. I am currently on Synthroid 100mcg daily, and Aldactone 10mg for adult onset acne by my Dermatologist. Since dx with Hypothyroidism I have gained 35 lbs. I am trying to get the weight off, but want to take an additional medication if it will not interact with my Synthroid. Can I take Phentermine or Hoodia without drug interactions? Please give me as much information as you deem relevant.

Thank you,

Stephanie T.
 Dr. Chan Lowe - Mon Mar 12, 2007 9:38 pm

User avatar Based on my references, there is no interaction between synthroid and phentermine. I have no data on Hoodia. Caution should always be used when mixing medications and in general should be avoided when possible.

Have you had follow up tests to ensure that your hypothyroidism is now under control? Weight gain is a symptom of hypothyroidism. If you are still low on thyroid hormone your metabolism slows down making it a) easier to gain weight and b) harder to loose weight already gained.

Hope this helps.

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