Ketamine is very different from the main chemsex drugs, as it is a dissociative hallucinogen that distorts perceptions and creates a sense of detachment. The crash following the use of methamphetamine in this manner is very often severe, with marked hypersomnia. Methamphetamine is used to create euphoria, "heighten sexual appetite", and increase sexual stamina. In some cases, these sexual encounters will sometimes occur continuously for several days along with repeated methamphetamine use. Methamphetamine taken in excess of amounts prescribed or recommended will prolong symptoms of intoxication for up to eight hours. Since stimulant drugs such as methamphetamine drastically delay the need for sleep, increase sexual arousal, and tend to inhibit ejaculation, PNP sexual encounters can continue for many hours or even days. On such sites, men often include notations such as "chems" or "PnP". It has been further described that "an entire subculture known as party and play is based around methamphetamine use." Gay men belonging to this subculture will typically meet up through internet dating sites to have sex. Methamphetamine is often used recreationally for its effects as a potent aphrodisiac, euphoriant, and stimulant. For this reason, it is considered "a public health priority". Some studies have found that people participating in such sex parties have a higher probability of acquiring sexually transmitted infections, including HIV/AIDS, by having unprotected sex with large numbers of sexual partners. The term slamsex is associated with users who inject the drugs. The drug of choice is typically methamphetamine, known as crystal meth, tina or T, but other drugs are also used, such as mephedrone, GHB, GBL, and alkyl nitrites (known as poppers). This can include unprotected sex during sessions with multiple sexual partners that may continue for days. Sociologically, it refers to a subculture of recreational drug users who engage in high-risk sexual activities under the influence of drugs within sub-groups. Party and play ( PnP), also called chemsex or wired play, is the consumption of drugs to facilitate or enhance sexual activity. Methamphetamine is the drug most associated with party and play.