Levothyroxine, Synthroid, & Me

I wanted to share something I learned about this week. Before I start, I must clarify that THIS IS NOT MEDICAL ADVICE so please check this out with your doctor. I am not a medical professional, just a patient who is sharing information about my own personal experience.

For many of us who have thyroid problems, we know that Synthroid is our lifeline. As for me, I had papillary thyroid cancer and had my thyroid removed. Those of us who are 'Synthroid Brothers & Sisters,' know how bad it gets if our dosage is off or we miss taking it. It is to this end that I share my personal experience in the taking of the generic Levothyroxine versus Synthroid.

I have been on Synthroid for the last ten years since my cancer. I've had dose adjustments between .125 mg to .150 mg. For the most part I've done well on Synthroid. Well, this past month or so, a new Florida law allowed Pharmacies to automatically fill all prescriptions with their generic equivalents without prior approval from the Insurance Company. So, as usual, I called in a refill for my Synthroid last month. My husband picked it up and brought it home for me. When I went to take my first pill from this new bottle I discovered that it looked quite different from my traditional Synthroid tablet. Upon further inspection, I saw that I was given the generic levothyroxine instead of the Synthroid that I requested. I also noticed it was more than half the price of Synthroid, so I went with it.

As the days progressed, I began to experience hypothyroid symptoms insomnia, migraines, lack of focus, stiff/sore muscles & cramps, the big D, well, you guys know what I'm talking about. I didn't think it was the new medication as I was told it was the equivalent to Synthroid. By the beginning of the 4th week of taking it, I was a MESS.

I began speaking with one of my Synthroid Sisters and we both shared with each other about how fatigued we were and how we needed to our TSH levels checked. Then, as a course of discussion, we discovered we both had been switched to generic levothyroxine at the same time. WHOA! So, we both looked up levothyroxine sodium on the web. Here's what we found out:

1. Generic and branded tablets of levothyroxine may differ:
- in the amount of levothyroxine they contain,
- the absorption of the levothyroxine into the body, and
- the distribution of levothyroxine throughout the body.
2. There are foods and other substances that can interfere with absorption.

• Avoid taking calcium and iron supplements within 4 hours of the medication.
• Avoid taking soy products within 3 hours of the medication as these can reduce absorption of the medication.
• Other substances that reduce absorption are aluminum and magnesium contained in antacids.
• Ketamine may cause hypertension and tachycardia and Tricyclic and tetracyclic antidepressants increase its toxicity.
• Lithium causes hyperthyroidism by affecting iodine metabolism of the thyroid itself and thus inhibits Synthetic levothyroxine as well.

3. Synthetic levothyroxine may have adverse side effects like: palpitations, nervousness, headache, difficulty sleeping, insomnia, swelling of the legs and ankles, weight loss and/or increased appetite.

Thought I'd share. I am not implicating the generic as not being as good just that I experienced hypothyroid symptoms during the month I was on it. It may be as simple as an adjustment in dosage. There could have been other factors that influenced this as well. Again, please check with your doctor and pharmacist, especially if you have been switched to a different medication that you usually take and begin experiencing symptoms.

Information for levothyroxine sodium used in this blog was found on the following websites:
http://www.medicinenet.com/levothyroxine_sodium/article.htm
http://en.wikipedia.org/wiki/Levothyroxine#Dosage.2C_precautions_and_side_effects