bronchitis
"Guaifenesin is great for my bronchitis. But, I have learned, that whether I take the liquid or tablet, I must eat 1st.  If I take this on an empty stomach, which is what I did about an hour ago, I have such a reaction it almost puts me on my knees. Luckily, within 15 mins of realizing what was going on, I was able to get something to eat. The 1st reaction was almost 20 years ago with the liquid, I ended up in the ER.  I didn't know what was wrong. Today I took a pill on an empty stomach & my stomach began to cramp severely within a short time.  This was a sinus/mucous relief tablet with guaifenesin. I'm okay now, but do not take guaifenesin on empty stomach! You don't want to try it first. I'll keep taking it, but eating first."