What effects does cannabis have on a person who has schizophrenia?

The effects should be considered uncertain at this point. There is some indication that, for the tiny minority of the population who has schizophrenia, it may make the problem worse. However, the evidence is not clear and the association could be the result of people with schizophrenic tendencies who are seeking cannabis as self-medication.

In general, recreational drugs of any kind should not be taken by anyone who has a problem with schizophrenia.

Answer

The studies linking cannabis to schizophrenia only tested for THC. CBD is another psychoactive chemical in cannabis. And it only showed that THC stimulates the part of the brain that causes paranoia. Paranoia is an element of schizophrenia, but it's not the only factor. Another thing everyone should know is that there was a pharmaceutical company that contributed money to this study. The drug it produced was for schizophrenia.

From personal experience marijuana helps schizophrenia, at least in some cases. I have a friend who has schizophrenia who smokes marijuana for it, and so far it's been working. He hasn't had any symptoms since he started smoking. I think that pharmaceutical company helped fund this study because they were worried about competition.

EDIT: I also found out he has bipolar disorder, which some studies suggest can be treated by cannabis so it could be that it's treating the bipolar disorder rather than the schizophrenia.

THC is in the hallucinagin family which LSD belongs-a powerful chemical often causing schzophrenia whether temporary or other. Patience who suffer this disease of complain of onother world or trip that is unwxplainable in ordinary logic-which seems to amnesia regular thinking much like the bizarre reasoning that LSD-lysergic acid creates