Now Piomelli's group has examined cerebrospinal fluid from 10 schizophrenic patients, taken for diagnostic purposes at the Medical College of Hannover in Germany. They found that fluid from schizophrenic patients had on average twice as much anandamide as fluid from people who didn't have schizophrenia (NeuroReport, vol 10, p 1665).

One explanation for the higher levels in schizophrenics is that the brain is attempting to compensate for a hyperactive dopamine system. It's the brains response to bring this dopamine activity down, says Piomelli. But the brain cannot keep the amount of anandamide high enough to lower dopamine levels, he says.

This might also explain why schizophrenics often smoke marijuana. The drug's active agent, THC, and anandamide both bind to the same receptor, so patients might be treating themselves, he says. But because pot does not act selectively in the brain, Piomelli does not consider it a useful treatment for schizophrenia. I don't think the patient wants to be high, he says. I think the patient wants to feel better.