Zofran Help!

Larissa
I have chronic nausea even before I got pregnant but now that I am pregnant (7 weeks) the nausea is unbearable. I've been prescribed zofran for years so I finally broke down and took one! 
I have friends who tell me they took it for all of there pregnancy and were fine. And then I read scary articles and I freak myself out! I'm calling my doctor today to make sure I'm okay taking them but I was wondering what ever else experience is with Zofran? 
Any constructive criticism or advice is appreciated!