L.-
Unfortunately, just about anything can make the baby gassy. We used Mylicon with our son, but our pediatrician warned us that you have to really keep up on it consistently, and even then, it's not really 100% effective.
A friend of mine, who grew-up in India, swears by Gripe Water. You can usually find it at most health food stores. it contains fennel and ginger extracts that are known to soothe your GI system, but I would highly recommend asking your pediatrician before starting anything like that.
The other thing that seems to really help infants with gas is laying them across your legs on their stomach and rubbing their backs (puts pressure on their tummies that helps alleviate pressure and pain). Our daughter loved to be held across her stomach at a few weeks old, and bending their legs into their abdomen (pick their feet up and push gently into their abdominal area) always helped alleviate gas, too.
Good luck.