As prostitution activities in this population are mostly drug driven, treatment of drug dependence can have a positive effect on that behavior. Meandzija et al. showed that the intravenous drug users they studied engaged in high-risk sexual behaviors, but methadone maintenance reduced sex for drugs or money exchange.

In fact, treatment may be crucial for reducing sexual risk in drug addicts, but it may be necessary to increase or find new strategies for risk prevention, as some studies show that there is no association between treatment and safer sexual practices. A longer treatment career may be effective as Longshore and Hsieh demonstrated that users with more lifetime treatment exposure had lower scores for risky sex. This is consistent with the hypothesis that successive episodes of treatment may have long-term cumulative effects on drug users’ HIV risk behavior. Until now, we have been discussing problems related to drug dependence, but we must now consider the influence of acute drug use and its possible influence on decision making regarding risky sex situations.

It would be reasonable to assume that the use of a mind-altering substance prior to sexual activity may result in impaired decision making about the whole situation, including prevention of STDs.
Research has shown that substance use (including alcohol, marijuana, methamphetamines and others) prior to or during sex, is a significant predictor of high-risk sexual behavior, regardless of sex, age, ethnicity or sexual orientation.

Nevertheless, some studies do not support the assumption of a casual relationship between substance abuse and risky sex even in high-risk samples. In Scotland, Leigh and Miller in a sample of more than 1,300 respondents from urban areas, examined alcohol or drug use in conjunction with sexual activity and the use of condoms and other contraceptives and concluded that people combining sex with alcohol or drugs are not necessarily more likely to engage in riskier sex. Miller et al. investigated risk taking related to sex and drug use to find that this behavior was neither entirely general nor entirely specific with distinct types of risk taking being distinguished.

Results from the study by Schafer et al., support an association between drug use (other than alcohol) and decreased likelihood of condom use with a new sexual partner. Individuals who used drugs and did not use condoms scored significantly higher on a scale assessing impulsivity, risk taking and sensation seeking. An explanation for the resistance or inability to change sexual risky behaviors among drug users has been advanced by Singer. This author proposes that sexual risk behavior may be understood and explained in the context of clients’ perception of themselves and their relationships, as a result of past traumatic events and current lifestyle.

There is sufficient evidence for considering that using drugs before or during sexual intercourse can, in certain circumstances, put the parts involved at risk of unwanted pregnancy or STDs. Prevention programs directed at occasional users of recreational drugs and risk prevention for drug addicts and their sex partners are thus a matter of health priority.

Particularly after the AIDS epidemic, health authorities became aware of the necessity of implementing measures to control the spread of STDs. In this context, researchers soon began to investigate the impairments in the practice of safer sex and, among many other hypotheses, they conjectured about the use of safe sex practices among people who were using mind-altering substances.

Thus, a considerable amount of research on the relationship of sexuality and drugs deals with the spread of HIV- and hepatitis-associated drug abuse and community efforts to prevent these infections. Could the use of these substances cloud the good judgment about a possible sexual situation in which the drug user is involved? Would people under drugs be less able to use safety measures regarding STDs? Or perhaps drug users are at risk not because of their drug use, but because of the characteristics of their personality?

First of all, it must be established that drug users do have a sex life. Sometimes, clinicians in drug therapy settings know that chronic use of drugs severely impairs sexuality and consequently they tend to disregard the sex life of their clients. Goldberg et al. stated that drug injectors with serious opiate and tranquilizer dependency are at least as sexually active as the general population. Our research shows that, at least for opioid-addicted men, there is a decrease in sexual activity, but the fact is that the majority of drug users, including drug injectors, are sexuality active with their partners or, in significant minority (mostly women) involved in prostitution.
Although some addicts may be reducing their HIV risk, abandoning the sharing of injecting equipment or the IV use altogether, they may maintain some risky sexual behavior. The levels of condom use, even for drug injectors, are low and inconsistent for both men and women.

The risk of HIV transmission among nonintravenous drug users is likely to be related to sexual transmission of HIV, particularly due to the prevalence of high-risk sexual behavior and STDs in this population.
Addicted women are more likely to have a sex partner who is a drug user and also to be living with a drug user. The same is not true for addicted men who, in many instances, have a healthy female for a sex companion or are living with a healthy female. The sexual risks involved vary, of course, with these different situations.

Healthy female partners of male drug users in stable relationships, although theoretically knowing the risks involved in using drugs may feel as though that risk would not apply to their partnership and act accordingly with a very low use of safety measures against STDs.

In this way, drug users can be at risk for STDs or putting at risk their sex partners as there are relatively high levels of sexual mixing between drug injectors and noninjectors and between drug users and nonusers. Prostitution can be a source of income for drug addicts. In a recent study, we found a significant number of female drug addicts engaging in prostitution activities, and the age at which these activities began correlated with the age at which they began the daily use of drugs. In this money for sex exchange, it seems that STD prevention is uncommon. High levels of unprotected anal intercourse are found among prostitutes and drug users.