What is with this bitter taste??

Anyone? Bueller? Since my surgery, I have had this faint, but always present bitter taste in my mouth. I was in a scopolamine fog for a couple of days after surgery, but I'm pretty sure it started even before I was given my first dose of Synthroid. It's a taste that I used to notice when I would occasionally take Lunesta a year or so ago for some chronic insomnia after my mother's death. Only, it's not as strong as that bitter taste. The only other thing I can think that it might be is the antibiotic, clindamycin, that I just finished. I guess that will be my answer if this bitterness goes away in a few days, since I just finished the last dose. Anyway....I'll do a search on the web as well, but is there anyone out there who tastes this as well?