I also have a hypothyroid condition. I am prescribed Levothyroxiine, 112 mcg. My last TSH or THYROTROPIN test in March was 3.47. I have been taking Levothyroxline for years, and I have been told once I began this regiment that it would be a lifetime thing. In recent months I have started to get fatigued, or maybe more descriptively -- I hit the wall by mid-day. On occasions I take an energy drink and they give me a boost for awhile to get through to the end of the work day. I only drink the zero sugar, zero calories brands, favoring Monster Zero Ultra when I do. I know, or have been told energy drinks are probably not the best thing for us to drink, but just about everything seems to fit that description. My chief concern is how bad are they? Are they a bad idea to take in addition to Levothyroxine? And can they be addictive, thus, mask a better method and solution to get that second shot of energy? I tried 5-hour energy, but frankly I wasn't all that impressed by the product. I am 71 years of age, but in otherwise good health, look 10 years younger, and I am actively involved in community volunteerism, and I work part-time overseeing a nonprofit. I surprised some people when I decided at 70 to go skydiving. When people see me that are amazed at what they perceive as my stamina for my age, but without an energy booster to supplement my Levothyroxine I would be exhausted by the end of the day. I finally watched video on Actalin to the end. Interesting thoughts requiring iodine, but before jumping that band wagon I decided to do a web search on Actalin and that is how I came across this site. Thanks for any comments.