People with a drug using personality are likely to do other drugs, though what you do/if you do other drugs that depends on your personality too. Like some people swear by marijuana, some people stay all natural, you know weed and shrooms. Me, I just like psychedelics in general, weed, lsd, shrooms, and whatever else. Then some people like to fiend over crack rocks...
Though once your in the lifestyle, smoking weed. Your open to new drugs, though I see once you start doing something other than weed then the real gateway starts. Well like, me and a couple friends were talking about this before and one of my friends suggested he felt like marijuana was a gateway, which got him to try mushrooms and acid once. Then me and my other buddy completely thought it was bullshit, if we wanted other drugs we would do other drugs.
Then there is drug dealers who may suggest other drugs, which you only will get if you really want to though.. Like the other day I got 5 hits of acid from my guy and he was like so and so has got some bomb ass ketamine right now..