Two doctors with Fibromyalgia wrote a book in which they reported symptom abatment by using Guiafenesin. This means wiping out all salicylates from your diet, as in aspirin and virtually all herbs, as salicylates block Guiafenesin's action.
Liquid Guiafenesin, like Robitussin I (only this contains menthol: get a cheap knock-off of Guiafenesin syrup without salicylate-loaded menthol) only works for a short time. So use MUCINEX, a time-release Guiafenesin tablet, which is cheapest at Eckerd's. There is also a prescription form, HUMIBID, which has two forms of Guiafenesin and which may be covered by insurance for some. Stay well hydrated with fresh, clean water as Guiafenesin enhances cell hydration, so you will need more and better water. O.K.? God bless!