TSH Stability of Levothyroxine Tablets Vs. Tirosint-SOL Oral Solution
After diagnosing hypothyroidism, many doctors start their patients out with levothyroxine tablets, the synthetic version of the T4 hormone. You'll recognize brands like Synthroid, Levoxyl, Unithroid, or Euthyrox. Conventional hypothyroidism guidelines then recommend that once your TSH level has stabilized in the fabled "normal range," you should be retested every year.
But here's the question: How stable is your treatment on levothyroxine tablets, versus oral solution (Tirosint-SOL)?
New research looked at more than a total of almost 1000 hypothyroid patients (around 650 taking Tirosint-SOL oral solution, and the rest on levothyroxine tablets) and followed them for two years. None of these patients had absorption issues.
After a year, 87% of the patients taking Tirosint-SOL oral solution had stable TSH levels. After two years, 81% of patients on Tirosint-SOL were still stable.
For the patients taking levothyroxine tablets, 81% were stable after one year, and only 73% were stable after two years.
Bottom line: The research findings suggest that the Tirosint-SOL oral solution is better able to maintain stable TSH levels over time compared to levothyroxine tablets. Something to think about, especially if you have fluctuating TSH levels with no obvious explanation.
Source: Antonelli, A et. al. "TSH Stability in Hypothyroid Patients in Treatment with Liquid L-Thyroxine," American Thyroid Association Annual Meeting Clinical Poster, October 2021, Poster 142, https://www.liebertpub.com/doi/full/10.1089/thy.2021.29115.abstracts
Learn More About Your Levothyroxine Options
If you’re interested in learning more about all your levothyroxine options, and the pros and cons of different types and brands of levothyroxine, check out my free educational program, the Levothyroxine Deep Dive. The program features 3 informative video webinars — watch any time, on-demand, on any device — a free full-length book to download, and a comprehensive website. You can find the Levothyroxine Deep Dive at www.mary-shomon.com/dive.
I had a terrible time with Tirosint-Sol.
I was very aware I needed to follow the directions precisely, and I did, but no matter how long I took each day to get every last drop of the medicine, my thyroid levels were out-of-whack.
It wasn't until I reverted to Tirosint capsules that life went back to normal.
I'll never get those 9 months back, so my advice to anyone who tries Tirosint-Sol and has a bad result after completion of the first prescription is to switch to the gel caps.