sinusitis
"I suffer from chronic sinus infections and have been treated with clarithromycin. While it got rid of the more severe issues (facial pain, horribly stuffed nose) I still didn't feel great after. Both times I ended up having to go to an ENT afterwards and start a stronger steroid and antibiotic. To top it off when I was on clarithromycin I had that terrible metallic taste in my mouth that would actually wake me up in the  middle of the night."