Robitussin Safe?

okay I had a list of medicines that were okay to take while pregnant well I lost the list and I can't remember which one was okay I've Googled and Googled different types of cough medicines and I believe Robitussin was okay I want to say it was on that list. this cough is killing me I refuse to suffer any longer. I bought some Robitussin I'm pretty sure I can take it does anybody else know if Robitussin is okay to take while pregnant? thanks in advance