Sorry you're scared. Which med is it? (I haven't been up to date with this thread.)

If it makes you feel better, pharmacists will refuse to fill a medication if they know there is a sizable risk of an extreme adverse reaction like death, paralysis, etc.. Heck, there were some recent questions about whether or not an anti malaria drug could cure COVID-19, but because it resulted in even a small percentage of deaths (I forget which country it was in, but it might've been in the U.S.), the FDA shut that option down immediately. Usually the FDA gives leeway on emergency meds like that considering the mortality rate of that drug is lower than the mortality rate of people on ventilators who were taking it, so that's saying how serious the U.S. takes things. We do not compromise. So a med that is inherently dangerous would be shutdown before it could even make it to market. The U.S. is VERY strict with meds and often rejects meds that other countries use because they deem the risk of adverse effects to be too high. We have high, high standards.

I suppose in theory that any med can technically cause death, but the risk for meds on the market causing that kind of effect is so insignificant that I think it's virtually nonexistent. As I said, the U.S. would ban it completely if it were truly bad. Lots of drugs have clinical trials that can last 10-15 years, so they are well studied and lethal conditions like SJS are warned about upfront, if the med has a decent risk of causing it.

More info: The State of Clinical Research in the United States: An Overview - Transforming Clinical Research in the United States - NCBI Bookshelf