Heymatt:

So, I was digging your column on schizophrenia, but when I read the last paragraph, I heard my own loud voice and it boomed, "Dios mio!" Matt, my buddy, in a town like San Diego, where a small but significant minority of locals pride themselves on the quality of the herbs they smoke, a lot of people need some explanation when they read this: "More and more, psychiatrists are seeing habitual smokers of the gene-tweaked, ultra-high-THC-content weed who develop similar psychoses." Can you shed a little more light on this bong-buster of a bombshell? I've, ah, got some friends who might be interested. Thanks, amigo.

-- Shane, via e-mail

Uh, so -- you like the idea of weed that makes you psychotic? Can't wait for that ultimate weed freak-out? To hell with couch cramp or the usual blissout. You crave the weed that makes you want to punch your roommate in the face. Well, we'll see about that.

So, what is it that, um, your friends are smoking now? Odds are, if it's common, ground-grown stuff, it has about a 5 percent THC content, maybe less. Mexican weed has been tested as high as 7 percent, Maui Wowie can run up to 10. The hundreds of types of hydroponically grown, indica-sativa crossbreeds that go under the general name "skunk" can have from 15 percent THC to the high 20s (laboratory tested), similar to most hash. But any weed, no matter how it's hyped, can have as little as 1 or 2 percent, based on lab tests. The level depends on growing conditions and the care taken during cultivation. The true high-THC weed is most easily available in Europe, especially England and the Netherlands, though it likely first came from the U.S. in the 1990s. The Dutch have developed and refined many hybrids. Southwestern Canada produces some of the strongest in North America.

I'm told that a lot of what's sold here as "skunk" isn't particularly high in THC. The extremes are the exception, not the rule. Your connection is a salesman, after all, especially at $500 an ounce. And High Times is not a scientific journal. These THC numbers come from government and medical testing labs.

As for the weed-psychosis connection, studies (mostly from Europe) indicate that the weed might not cause the psychosis or schizophrenia; it's more likely that people with the genetic or behavioral predisposition to the diagnosis can be pushed around the corner by heavy use. Young teenagers seem to be particularly at risk because the frontal cortex of the brain is still being formed at this age, and that's the area most responsible for regulation of emotions, judgment, analysis, and planning. The jury's still out, though.