I consider myself a "Good Christian" although I don't believe in God (I DO believe Jesus Christ existed and that he preached a good way of living, tolerance etc.). Obviously in history, very bloody wars have been waged in the name of Christianity, but I don't believe these hold true with the teachings. I feel the only people I am disrespecting when I take drugs are myself (because of the damage the drugs can and do, do), my family and friends (because I know how much they care about me and would be devestated if anything happened to me.) and to an extent people who don't have a healthy body to abuse.
So, yes, I think you can still be a good Christian and take drugs.