I have taken guaifenisen for years and it has helped. 400 mg. It has gotten harder to find. I prefer the plain without additives but. . . . There are plenty time release. My ENT's have said it can't hurt me. It is also the fibromyalgia protocol drug so it can help that, too. Costco used to sell big bottles of it. Now Walmart has little bottles of it. Not as good I don't think but. . . it works. It's a decongestant.