If one of my parents had schizophrenia, I might go for a chat with my doctor to reassure myself. Drugs (legal / illegal / perfectly natural / perfectly unnatural) might all come up with your doctor but it's best to avoid them if they're old-fashioned / likely to toe the governement line. But I doubt I'd go looking for a quack opinion unless it was offered honestly. You could include hallucinogens in the mental illness debate. The US wanted to develop them to use them as chemical weapons (LSD) yet many people (myself included) think they're the best thing for a damaged mind.
RE: Cons of cannabis