"I have a very sensitive stomach, most antibiotics get me extremely sick. Biaxin is the only one I can take that doesn&#039;t completely destroy my stomach. The only side effect I get from this is a bad bitter taste in my mouth (usually about a half hour or so after taking it) and its obviously worse at night &amp; in the morning. However, I rather have that taste then have the runs, nausea or vomiting. I also take probiotics with this - the best ones I can recommend are the &quot;Integrative Probiotic Pearls&quot; yeah they are a little pricey but they work well when taking antibiotics. (I got at pharmacy, and my pharmacist recommended these specific ones). *BEST ADVICE* Chew a lot of gum/mints in between dosages, you&#039;ll get used to the taste after a few days"