I have heard of using robitussin to help conceive. I am not sure if it works or not. However I was taking cough syrup when I did convceive this last time. I don't know if that was the cause though. I don't think that it would hurt to try.
Make sure the only active ingredient is guaifenesin!
It helped me get more CM! I hadn't had ANY for a year and then I used Mucinex (KIDS) and I had CM!!!!!!!!!!! I didn't get pregnant but it did make me hopeful!
i guess it works different for everyone, it does not help you get more cm, all it does is thin out the cm you already produce. I used it last cycle but i didnt notice my cm to be any thinner.