Metronidazole
"I was prescribed Metronidazole for BV, I was severly nauseas 2 days after starting the doses, I couldn't eat more than a few bites of any of my meals... even the sight of food turned my stomach!  The taste is rancid, it almost has a weird/nasty feeling in your mouth, too.  But my symptoms seem to have cleared up, I didn't finish the full 7 day dose, per my Dr since symptoms cleared and nausea was so bad, I was advised I could stop with only 2 doses left.  I will never take this antibiotic again, it feels awful being nauseas, never mind that severly and for that length of time!  Gel for me next time, if needed!"