Clarithromycin
"I was on Clarithromycin and Amoxillin (  proton pump inhibitor omeprazole) for a week (h.pylori). First four days felt like hell, then my body slightly adjusted to the poison and it was easier, also I found that I can relieve the horrible bitter sewage like taste in my mouth with a chewing gum. Once I took two Amoxillin 1000mg tablets instead of Amox. Clarithromycin, there were zero effects, while with clarithromycin added comes the horrible taste in mouth, dizziness and general ill feeling. I was dying few hours after taking my final dose of those antibiotics, had to call an ambulance, felt like my heart was stopping, they pumped me with something and I survived, one star above 1 because I can still write this review 2 days after last dose"