Pegasys Interferon and Hashimoto's disease

[Dusty777]

Has anyone, with Hashimoto's, had any adverse side effects while using Pegasys? Ever since I was switched from Hydroxyurea to Pegasys, my body has had an explosion of pain, ranging from headaches to GERD to sinus issues and beyond. Trying to figure out if it's the combination of the thyroid disorder and the interferon, or I'm just getting older and falling apart. Appreciate any input - thanks

[hunter5582]

Pegasys can have adverse effects that include arthralgia, myalgia, and thyroid issues. Pegasys has a caution for pre-existing thyroid disease. If these symptoms are new, starting after initiating treatment with Pegasys, then it is quite reasonable to think that you are having a reaction to Pegasys. This is an issue that you need to discuss with your MPN care team.

Hope you find resolution soon. All the best.

[Mishie14]

I don't have Hashimoto but do have hypothyroid for which I have taken levothyroxine 75 MCG Tabs 5 days per week for some time before and since ET diagnosed in 2022. Checked with endocrine doctor before starting peginterferon. He wanted immediate thyroid blood tests before first injection for baseline and I now get thyroid blood tests and exam every 6 months as a precaution. Peginterferon dose started at 45 weekly and slowly up to 90 now still weekly with good results. The levothyroxine dose has not changed and I don't have any worsened thyroid issues. So far so good. Please check with your care team for help understanding what is causing your side effects. Hoping your discomfort gets solved soon. Stay safe.