Hey, I don’t know your whole story, but I had a very similar total intolerance of levo that was a huge problem and took forever to get solved - in my case, I found out much later that I had INSANELY low iron and ferritin. Have you had yours checked? I got an iron infusion to bring my levels right back up to normal, and now my experience with the levo is totally different! There’s still some normal ups and downs of adjusting like any hormonal shift, but I am not having the terrifying mental effects from before. More on reddit.com

I can see colors properly again! Had no idea that my perception of color had been sort of muted for decades. After a few months on levo I was shocked at how red, magenta, and pink flowers looked almost psychedelic, they became so vivid and bright. Would never have made the connection until a friend shared this study with me: https://pubmed.ncbi.nlm.nih.gov/25960961/ More on reddit.com

I started levothyroxine last month. About a week after I started I felt amazing. My spouse said I was a completely different person. I could feel it too. It was like I mentally stepped up into my body. I was happy. For years I had experienced the world through a fleshy cage always reacting to external stimuli, like a robot. Now I actually felt in control. I no longer had to take breaks every 10 minutes, both mentally and physically. I was no longer fully wiped out after an hours worth of work. I felt like I had gained superpowers. That window only lasted about 8 days. Then the hyperthyroidism symptoms started. I had nervous energy, my heart thumped loudly and erratically, I was sweating buckets, I had dreams of dying, and the damn fatigue returned. My general practitioner had me on 175 mcg of levothyroxine. I thought i was just settling into it. Only recently did I find out that this is a super high dose. Most doctors that know what they are doing start low and work up. And I now know why. After calling my doctor, he told me to go off it and start a lower dosage in a week. I start on 150 mcg tomorrow. I'm also going to an endocrinologist next month, hopefully he'll know what he's doing. This yo-yoing is messing with my head. After seeing how good I could have it, I can't wait to get back there again. I've read it can take up to a year to get the dose right. God I hope it goes faster. Good luck. More on reddit.com

It's a replacement hormone for what you're not making enough of. You can have symptoms from over or under-replacement, but those are common to all of us when we're not at the right level. You MIGHT have side effects to one or more of the fillers in the pills, but not to the levothyroxine itself. Your body can't tell the difference between natural and synthetic T4 hormone. Ignore most of the scary stories on the Internet. Out of billions of people, there's always a few with issues.  There's 23 million people in the US alone on hormone replacement due to hypothyroidism, and the majority of us are doing fine. More on reddit.com