What causes HPPD?
HPPD is defined to be caused by taking ‘hallucinogenic’ drugs, but its root cause is poorly understood. Dr. Henry Abraham ( a leading researcher in this area) believes that HPPD may be partially genetic though he says that he knows of no published evidence [personal communication – tacovan]. It seems to be most commonly related to LSD use, perhaps because LSD is the most common hallucinogen, but there are also reports of HPPD being caused by other psychedelics such as mushrooms, MDMA, MDA, 2CT7, 5-MEO-DiPT, etc. There are a few people who have HPPD-like symptoms who have never taken any drugs, but the definition of Hallucinogen Persisting Perceptual Disorder does not include these individuals. Based on anecdotal evidence HPPD subjects fall into two broad categories. A large percentage (probably the majority) got HPPD fairly early in their experimentation with hallucinogens. They also seem to get fairly severe cases of it. Dr. Abraham also confirms that this appears to be the case and s
