CHEMSEX. ΟΙ ΚΙΝΔΥΝΟΙ ΓΙΑ ΤΗΝ ΥΓΕΙΑ

Party and play (PNP and PnP) is a subculture of recreational drug users who engage in high risk sexual activities under the influence of drugs within groups. It is also called chemsex and it is described "as an enormous risk."
The prevalence of risky, unprotected sex – a natural outcome of being high and impulsive – is worrisome, as the result (aside from hangovers, comedowns and exhaustion) is leading to a rise in HIV, syphilis, gonorrhea and hepatitis C.

Medical risks

Aside from the inherent risks involved with drug use, health officials have found a strong correlation between drug use and unsafe sex practices. The practice has been credited with the emergence of a new, more virulent form of HIV. The strain has been described as having the ability to produce AIDS symptoms in as little as four months. As such, PNP practices are cited as the cause of rising HIV rates in the gay and bisexual male community and other men who have sex with men. San Francisco's Stop AIDS Project and the Mayor of San Francisco's Crystal Meth Task Force have reduced methamphetamine use from 18% in 2003 to 10% in 2005 of gay and bisexual San Franciscans PNPing The STOP AIDS Project has been heavily involved due to the common link between methamphetamine use and sex.

The same drug-induced loss of inhibitions makes PNP enthusiasts more vulnerable to more immediate threats, such as robbery, date rape, or assault by someone whom they meet for sex. The term party and play - and pay has emerged as a warning that partying and playing leads to bareback sex which increases the chances of contracting HIV and may result in other consequences such as neurological damage and resistance to HIV drugs. 

Methamphetamine can cause sores and abrasions in the mouth which can turn typically low-HIV-risk sex acts such as oral sex into very-high-risk sexual activity.
These drugs tend to inhibit penile erection. Because ischemic priapism causes the blood to remain in the penis for unusually long periods of time, the blood becomes deprived of oxygen and can cause damage to the penile tissue itself. Should the penile tissue become damaged, it can further result in erectile dysfunction or disfigurement of the penis. In extreme cases, if the penis suffers from severe vascular disease, the priapism can result in penile gangrene

Statistics

Men who PNP with methamphetamine, cocaine, MDMA, and ketamine are twice as likely to have unprotected sex (meaning sex without using a condom), according to British research from 2006. The study also found that up to 20% of gay men from central London gyms had tried methamphetamine, the drug most associated with PNPing.  (en.wikipedia.org)