How can I help a self destructive friend?

He's at college and the past year has been pretty tough for him health wise, he's been diagnosed with a spinal problem and inherited some sort of gene mutilation linked to cancer so he's had to deal with a lot. In the past three months or so he's been drinking a lot more often, usually around 4-5 times a week and I've found empty bottles of vicodin in his bedroom. When I went out with him to a party last night I saw him down two bottles of jager and get into a fight. He's scaring me, how can I help him?