How long should i take robotussin? is it safe to take it daily for a month or two to thin and loosen mucus?

Robitussin (guaifenesin): Yes but check with ahealth care professional for what else you can do to clear the mucous up since that is a long time.

Guafenesin: Guafenesin probably is, but dextrometorphan is not. Only these medications for a short time: 1- 2 weeks.

Robitussin (guaifenesin): If you have to take for such a long period of time, it is time to find out the cause of your congestion. It is possible you you have allergies or asthma. You should be evaluated by an allergist.