Freda - The green on the screen of that link was kinda sickening so I copied a part here,

"Chronic effects of the drug can be positive and negative. Positive effects include spiritual contact and self-exploration; the most severe negative effect is known as LSD psychosis. LSD has shown to have therapeutic usefulness, although research has been severely limited for the last several decades. LSD psychosis has been linked to forms of schizophrenia, and thus, to some physiological disorders -- it appears to be dependent on the user, and not on the drug."

I'd say that just about sums it up.