Hallucinogen persisting perception disorder: A literature review and three case reports

The paper describes diagnostic criteria, clinical presentation and types of hallucinogen persisting perception disorder (HPPD), as well as current approaches to the treatment of this phenomenon using available scientific sources. Three case reports are also presented to demonstrate different types of this disorder. The first case report describes a 23-year old patient with a previous history of cannabis consumption who reported HPDD type I after the use of psilocybin mushrooms with small amounts of alcohol and hash. A month later, after cannabis use, the same visual and auditory distortions appeared again. During the following year, hallucinations recurred with the consumption of natural cannabinoids but not with alcohol intake. The symptoms have reduced within a year. Surprisingly, both other cases belonging to HPDD type II appeared in patients who consumed ecstasy, although MDMA is generally not considered a hallucinogen and hallucinations are not frequently reported after MDMA consumption. In both cases of HPPD type II after the use of ecstasy, the condition was very stressful and frightening. Both patients sought medical help and received tofisopam, lamotrigine and sertraline. After that, in both cases visual impairments have smoothed, but have not passed completely. Scientific sources suggest that HPPD may affect more than 50% of hallucinogen users and this disorder is often underdiagnosed. Therefore, patients suffering from HPPD can present in various clinical settings, and clinicians should be aware of this condition.