ibromyalgia
"I have been using Mucinex for 6-9 months for Fibromyalgia and Chronic Cough (20 years).  Started with 600mg twice a day for about a month, then I switched to 1200mg twice a day for about 2 months.  1200 was way TOO Much, it made my joints burn with pain and my left leg swelled up. I switched back to 600mg twice a day - still had the pain and swelling - then dropped the dose to 600mg once a day - the swelling went down and the pain was much less.  I got very tired -hard to work.  All this time the Mucinex worked to control the Fibro and helped me to function and think clearly.  I will try an even lower dose of Mucinex. Can't get it over the counter. I've been off the medicine for 2 days with lots of rest. In a few days I'll be back on with a lower dose."