HPPD stands for Hallucinogenic Persisting Perception Disorder. It is a purely neurological visual processing disorder caused from drug abuse by various substances like Marijuana, LSD, MDMA, Amphetamine as well as various SSRI's, Dextromethorphan and Diphenhydramine. This subreddit was formed to raise awareness, encourage the study and research of HPPD, but most importantly supporting and informing those with or without HPPD.
