Worst comedown IMO is a tie between alcohol and coke. Hangovers are fucking horrible and it's one of the reasons why i never was a huge drinker. I started off with alcohol like most people when they begin partying and that's when I was drinking every weekend at parties, waking up with bad headaches combined with severe nausea, stomach pain, and diarrhea. I remember one of the worst hangovers I had was from nasty ass Bacardi, I was hungry so my bf at the time took me to Togo's and before I even ordered my food I ran to the bathroom and puked like 4 times and it hurt really bad. Hard liquor, especially Hennessy, Bacardi, and sugary mixed drinks are the worst culprits. The worst liquor I've ever had was this shit called Black Hennessy, I swear I took one fucking shot and it had me running to bathroom to puke my brains out. Cocaine has a pretty nasty comedown as well, very similar to the meth comedown except what makes it even worse is the unbelievably long, intense headaches I would get the day after railing lines all night. Holy shit I felt like I wanted to die. At first the pain would start off in my forehead, then slowly spread to my temples, then it would keep working it's way up to the top of my head and finally to the back. It would last for hours too. I'm pretty sure some of the worst headaches I've had in my life were from the coke comedown. On top of that my nose would be soooo stuffed up I could hardly breathe and I would have to breathe out of my mouth which would be as dry as a desert no matter how much water I drank. I notice that the more coke I did, the worst the comedown was. I won't even fuck with coke anymore because of it, the high isn't worth it all, especially compared to meth. I can't even imagine how people can become addicted and do it everyday.
The worst comedown of my life was after a long night of partying in a hotel on New Years when I was 20. My day started off with smoking a few bowls of shards like usual, then I met up with some friends and smoked a bunch of weed, then we went to the bar inside the hotel we were at and I got so shit faced off Long Island Ice teas I could barely walk and my friend had to carry me to the room. He then pulled out a huge bag of Molly and I ate/snorted so much I couldn't even feel the alcohol anymore because I was rolling so hard. Then huffed a few nitrous balloons and almost passed the fuck out, then finally snorted a shit load of coke. On top of this there were blunts being passed around all night. I'm lucky I didn't end up in the hospital that night. Holy fuck the comedown was one of the worst feelings I ever experienced in my life, it felt like I was being poisoned to death. I literally felt aches and pains deep inside my bones and organs due to all the toxins being forced to leave my body. My stomach and intestines felt like they were being twisted and my head felt like someone was punching my brain.