Substance Use, Medications for Sexual Facilitation, and Sexual Risk Behavior Among Traveling Men Who Have Sex With Men : Sexually Transmitted Diseases

Secondary Logo

Journal Logo


Substance Use, Medications for Sexual Facilitation, and Sexual Risk Behavior Among Traveling Men Who Have Sex With Men

Benotsch, Eric G. PhD*†; Seeley, Salvatore MSW; Mikytuck, John J. BS§; Pinkerton, Steven D. PhD; Nettles, Christopher D. MA*; Ragsdale, Kathleen PhD

Author Information
Sexually Transmitted Diseases 33(12):p 706-711, December 2006. | DOI: 10.1097/01.olq.0000218862.34644.0e
  • Free

THE DEMOGRAPHICS OF AIDS IN the United States have changed over the past decade, but the majority of new HIV infections continue to occur among men who have sex with men (MSM).1 Recent studies have documented a resurgence of risk behaviors among MSM, perhaps partly as a result of the perception that AIDS is not as serious in the era of effective antiretroviral treatments.2,3 The risk behaviors of MSM therefore continue to be an important area of investigation for HIV primary prevention work.

Recent research has documented heightened substance use and sexual risk behaviors in MSM who are traveling on vacation.4–6 For many vacation destinations, an expectation exists that travelers will consume alcohol and other substances, seek new romantic partners, and engage in disinhibited behavior.7,8 Away from the time constraints and social expectations of their everyday lives, travelers may be more inclined to make high-risk choices.8 Some destinations advertise themselves as providing an uninhibited, carefree atmosphere where “anything goes” and anonymity is preserved.9 For example, as part of its current marketing campaign, Las Vegas declares, “What happens in Vegas, stays in Vegas.”10

Travel and Risk Behavior

A number of studies have documented disinhibition, heightened substance use, and high-risk sexual behavior among leisure travelers.7,11–19 The majority of this research has been conducted with young, heterosexual adults. In one study, Bellis and colleagues found that 26% of the men and 14% of the women in their sample of young adults reported more than one sexual partner during a brief overseas holiday.7 Similarly, Apostolopoulos et al documented high rates of risk behavior among young adults traveling on spring break.11

A small number of studies have examined the risk behavior of MSM on vacation.4–6,20 Crosby and colleagues documented high rates of risk behavior in men attending a sex resort in the southern United States.20 Related research has documented risk behavior among MSM attending more mainstream resort areas. For example, Clift and Forrest found that 52% of British MSM reported sex with a new partner while on vacation and that 30% reported sex with 3 or more new partners.4 In a similar study conducted in the United States, Whittier and colleagues collected data from men vacationing in a popular east coast beach town. Participating MSM reported sexual behavior during their time at the resort and for the previous 60 days spent in their home communities.6 Men on vacation reported 11 times more nonmain sexual partners with whom they had engaged in unprotected anal intercourse at the resort community versus at their homes.

Substance Use and Risk Behavior

Substance use has long been noted as a factor associated with high-risk sex among MSM.21–24 These associations are particularly strong when drug use occurs in conjunction with sexual activity. Associations between substance use and sexual risk behavior have been documented in MSM using a variety of substances, including alcohol, cocaine, methamphetamine, “poppers” (nitrites), and “club” drugs.25–29 In recent years, use of Viagra (sildenafil citrate) has become popular as a sexual enhancement aid among some segments of the MSM community.30 Previous research has documented an association between Viagra use and high-risk sexual behavior.23,31–33 For example, Kim et al reported that one in 3 gay men seeking sexually transmitted disease clinic services in San Francisco had used Viagra in the past year.30 In this study, Viagra users had higher numbers of partners with whom they had engaged in anal sex and higher rates of unprotected anal sex with a serodiscordant partner. MSM travelers who expect to engage in sexual activity while traveling may use Viagra as a facilitator of sexual activity. One study examined associations among Viagra use, substance use, and sexual risk behavior among MSM traveling to a sex resort. In this study, Viagra use was associated with use of other substances, including cocaine and ecstasy, but was not significantly associated with higher sexual risk.34

However, it is not clear if MSM traveling to traditional resort destinations (as opposed to sex resorts) also use Viagra or related medications in an effort to boost their sexuality. In the last few years, 2 new medications, Levitra (vardenafil) and Cialis (tadalafil), have been approved for the treatment of erectile dysfunction. Levitra, Cialis, and Viagra work by active inhibition of the phosphodiesterase type 5 (PDE-5) enzyme.35 All PDE-5 inhibitor medications facilitate sexual activity; however, these drugs’ sexual-enhancing effects differ slightly. Cialis is a longer-lasting medication, effective for up to 36 hours. Levitra has a comparable duration of action as Viagra but is more potent and specific in its effects.35 Use of these 2 newer medications by MSM has not been thoroughly documented in the literature and their relationship to sexual risk behavior is unknown.

The current study builds on previous work with MSM travelers by assessing substance use and sexual risk behaviors in MSM attending 2 mainstream resort areas popular among gay men and by exploring associations among the use of PDE-5 inhibitors, sexual risk behaviors, and use of other substances. We anticipated that substance use and use of PDE-5 inhibitors would be associated with sexual risk behavior in this sample.

Materials and Methods


A brief survey was administered to MSM recruited in Rehoboth Beach, Delaware (n = 200) and Key West, Florida (n = 104). The study sites were chosen because they are popular tourist destinations among MSM and because they are located near areas heavily affected by HIV. Overall, Florida ranks fourth and Delaware ranks fifth among U.S. states in AIDS prevalence.36 Data were collected simultaneously in both sites over a 4½-month period spanning June through September 2004. Data collection was not conducted in conjunction with specific cultural events (e.g., Gay Pride celebrations), but rather during “typical” summer travel periods. All study procedures and materials were approved by the Institutional Review Board of the Medical College of Wisconsin.

Key West participants were recruited from bars serving primarily gay clientele (50%), in the gay section of Duvall Street (30%), and from gay guest houses (20%). Rehoboth Beach participants were recruited on the beach (90%) and from bars serving primarily gay clientele (10%). Participants were told that the survey was about the behavior of men on vacation, contained personal questions about their sexual history and substance use, was anonymous, and required approximately 10 minutes to complete. No incentive payment was offered; however, participants were informed of services available in the area and the availability of free prevention materials, including condoms. More than 70% of men approached in Key West and more than 90% of men approached in Rehoboth Beach agreed to participate.

A total of 304 men completed questionnaires. To ensure that we were including in the analyses only individuals who were visitors to these areas, we asked participants to provide their home zip code. Men who provided a home zip code indicating that they traveled at least 50 miles to visit the study site were classified as visitors. Some participants were ineligible because they self-identified as heterosexual and reported no male sex partners (n = 9), reported a home zip code that indicated they traveled less than 50 miles to the study site (n = 5), or reported no zip code and therefore could not be classified as a visitor (n = 11). In addition, 11 participants (3.6%) were eliminated for problematic or random responding (e.g., circling all possible response choices). Of the 304 men who completed a survey, 268 (88%) were included in the analyses. The Rehoboth Beach and Key West subsamples were comparable in demographic characteristics and risk behaviors and thus were combined for data analysis purposes.


Participants completed a 2½-page self-administered anonymous survey that included questions assessing demographic information, time spent in the study location, substance use, and sexual behavior.


Participants were asked their age, years of education, ethnicity, home zip code, sexual orientation, and HIV status.

Days Since Arriving at the Study Site.

We asked participants how many days they had spent in Key West or Rehoboth Beach on their current trip.

Sexual Behavior and Disclosure of HIV Status to Partners.

Participants reported the total number of times they had engaged in protected and unprotected receptive anal sex and protected and unprotected insertive anal sex during their present trip. They also reported the number of times they had engaged in unprotected receptive and unprotected insertive oral sex. For each of these behaviors, they also reported the total number of sex partners with whom they had engaged in the behavior. In addition, participants reported whether they had asked all of their sexual partners about their HIV status and if they had disclosed their own HIV status to each of their sexual partners.

Substance Use.

Participants were asked separate yes/no questions concerning whether they had used a variety of substances during their current trip: marijuana, cocaine, ecstasy, LSD, methamphetamines, poppers, ketamine, rophynol, or GHB. Street names were provided for several of the drugs. Participants also responded to a yes/no question that asked if they had used alcohol to the point of intoxication during their trip. Participants were asked the number of times they had anal sex after having too much to drink and the number of times they had anal sex after using drugs since arriving at the resort destination.

PDE-5 Inhibitor Use.

Participants responded to yes/no questions asking if they had used Viagra, Levitra, or Cialis during their current trip.

Data Analysis

All surveys were examined for inconsistencies and invalid responses. Missing data were omitted from analyses, resulting in slightly different sample sizes for various statistical tests. Because distributions of sexual behavior were highly skewed, nonparametric analyses (Mann-Whitney tests) were used as recommended by Hays.37 Use of substances was measured categorically; analyses examining likelihood of substance use utilized the frequency chi-squared test.37 The relative contribution of various factors in predicting unprotected anal sex was examined using a sequential logistic regression analysis.38 Two-tailed significance levels were used for all statistical tests.



Among the 268 eligible participants, the mean age was 38.1 years (standard deviation [SD] = 9.7). The sample was well-educated, with 90% reporting at least some college education. The majority of the sample was white (83.4%), with the remainder being Latino (10.9%), black (2.6%), Asian American (1.5%), or other/mixed ethnic heritage (1.5%). The sample represented diverse regions of the United States; participants reported 183 distinct home zip codes, representing 23 U.S. states and the District of Columbia. U.S. participants traveled a median of 155 miles from their home to the study site. International participants indicated traveling to the study sites from Canada and Europe (n = 10). Most participants self-identified as gay (93.6%), 6% self-identified as bisexual, and one individual (0.4%) self-identified as heterosexual but was retained in the sample because he reported male sexual partners during his trip. Participants were most likely to report that they were HIV-negative (86.8%) with 7.8% reporting that they were HIV-positive and 5.4% indicating that their HIV status was unknown. At the time of survey completion, participants had spent an average of 3.6 days on their current vacation (SD = 3.8).

Sexual Behavior and Disclosure of HIV Status

During their present trip to Key West or Rehoboth Beach, 53% of participants reported having no anal or oral sex (protected or unprotected). A total of 24% (n = 65) of participants reported having unprotected anal sex and 39% (n = 77) reported having unprotected oral sex. Among the 47% of the sample that reported they were sexually active during the present trip, 30% reported having one partner with whom they engaged in unprotected insertive anal sex and 3% reported having 2 or more unprotected insertive anal sex partners. Thirty percent of sexually active participants reported having unprotected receptive anal sex with one partner, and an additional 2% reported having unprotected receptive anal sex with 2 or more partners. Overall, sexually active men reported a mean of 1.33 unprotected anal sex acts (SD = 2.45) during their brief stay in the vacation destination.

More than half (57%) of the sexually active men reported having anal sex with a partner of unknown HIV status. A similar number (52%) did not disclose their own HIV status to all of their sexual partners. HIV-positive participants were significantly more likely to disclose their HIV status to all of their sexual partners (83%) relative to HIV-negative participants (40%, chi-squared [1, N = 88] = 4.41, P < 0.05). Participants’ own HIV status was not associated with asking sexual partners about their HIV status.

Substance Use

Overall, 56% of the sample reported drinking until they were intoxicated (n = 147), and 16% (n = 42) reported using at least one illegal substance while on vacation. Other than alcohol, the most popular psychoactive drugs were marijuana (13% [n = 34]), poppers (9% [n = 24]), and cocaine (4% [n = 11]). “Club” drugs were used by small numbers of participants during their stay: ecstasy (3% [n = 9]), ketamine (0.8% [n = 2]), methamphetamines (0.4% [n = 1]), GHB (0.4% [n = 1]), and rophynol (0.4% [n = 1]). No participant reported using LSD. Overall, 6% of the sample (n = 15) reported using 2 or more illegal psychoactive substances during their stay in the resort area.

Substance Use and Sexual Activity

Relationships between sexual risk behavior and the more frequently used substances are shown in Table 1. Individuals using poppers, ecstasy, and ketamine during their stay in Key West or Rehoboth Beach were significantly more likely to report unprotected anal sex. We also asked participants the number of times they had engaged in anal sex after having too much to drink or after using drugs. Overall, 13% of participants reported having anal sex after drinking too much, and 5% reported having anal sex after consuming drugs. Use of alcohol in conjunction with anal sex was significantly correlated with the use of other drugs in conjunction with anal sex (ρ = 0.44, P < 0.001).

Associations Among Substance Use, Phosphodiesterase Type 5 Inhibitor Use, and Unprotected Anal Sex in the Resort Area

Substance use in conjunction with sexual activity was associated with high-risk sexual behavior. Consuming alcohol before anal sex was correlated with the number of unprotected receptive anal sex acts (ρ = 0.33, P < 0.001) and the number of partners with whom participants had engaged in unprotected anal sex (ρ = 0.35, P < 0.001). Alcohol use in conjunction with sex was also associated with unprotected insertive anal sex (ρ = 0.34, P < 0.001) and number of insertive anal sex partners (ρ = 0.33, P < 0.001). In addition, having anal sex after drinking too much alcohol was negatively correlated with asking sexual partners about their HIV status (ρ = −0.13, P < 0.05). Using drugs in conjunction with sexual activity showed a similar relationship to unprotected insertive anal sex. Drug use was correlated with total unprotected insertive acts (ρ = 0.20, P < 0.01) and unprotected insertive anal sex partners (ρ = 0.24, P < 0.001).

Use of PDE-5 Inhibitors

Overall, 11% of the sample reported taking one or more PDE-5 inhibitors during their vacation. The most popular drug was Viagra, used by 6.8% of the sample, followed by Levitra (3.8%) and Cialis (2.7%). A small percentage of men (2.3%) reported taking 2 or more PDE-5 inhibitors while in the resort area. Individuals taking these medications ranged in age from 23 to 67 (mean = 42.89, SD = 9.26) and were significantly older than nonusers (mean = 37.30, SD = 10.47, t[258] = 2.97, P < 0.01). Table 1 shows the relationship between use of each of these individual medications and likelihood of engaging in unprotected sex in the resort community.

Table 2 displays more specific sexual risk information for individuals using PDE-5 inhibitors. As seen in Table 2, individuals who used these medications reported higher overall rates of HIV risk behavior. Individuals who took medication for sexual facilitation also were significantly more likely to use psychoactive substances, including marijuana, ecstasy, poppers, and ketamine (see Table 3). Users and nonusers of PDE-5 inhibitors did not differ in their use of alcohol to intoxication, cocaine, methamphetamine, or other substances.

Sexual Behavior Among Users and Nonusers of Phosphodiesterase Type 5 Inhibitors
Other Substance Use Among Users and Nonusers of Phosphodiesterase Type 5 (PDE-5) Inhibitors

Multivariate Test of Association Among Demographic Factors, Use of Substances in Conjunction With Sexual Activity, and Medications for Sexual Facilitation

Given past findings suggesting that multiple factors influence high-risk sexual behavior, we performed a sequential logistic regression analysis to determine the independent association of the use PDE-5 inhibitors with unprotected anal sex after controlling for factors previously identified as associated with risky sexual practices. Demographic characteristics, use of alcohol and street drugs in conjunction with sexual behavior, and use of medications for sexual facilitation were used to predict engaging in unprotected anal intercourse, as shown in Table 4. Demographic factors were entered on the first step as control variables. Use of alcohol and drugs in conjunction with sexual activity were entered on the second step and significantly added to the prediction of sexual behavior (chi-squared [2, N = 246] = 21.71, P < 0.0001). Alcohol use in conjunction with sexual activity, in particular, was a significant risk factor for engaging in unprotected anal sex after controlling for the influence of other factors. Use of a PDE-5 inhibitor was entered on the final step and significantly added to the prediction of high-risk sexual behavior (chi-squared [1, N = 246] = 4.66, P < 0.05). Thus, use of these medications was significantly associated with participation in unprotected anal sex in the resort area, even after controlling for demographic factors and other substance use in conjunction with anal sex.

Sequential Logistic Regression Analysis Predicting Unprotected Anal Intercourse versus No Unprotected Anal Intercourse


In the current study, many participants reported low rates of risk behaviors. However, a significant minority had engaged in behavior that could place them at risk for HIV and other sexually transmitted infections, including unprotected anal sex and substance use in conjunction with sexual activity. More than half of the sexually active men reported having anal sex with a partner of unknown HIV status and a similar number did not disclose their own HIV status to all of their sexual partners. Risk was highest for individuals who used medications for sexual facilitation or who used alcohol or drugs in conjunction with sexual activity.

Consistent with previous research, substance use in the current study was associated with high-risk sexual behavior.27,28 Away from the constraints of their everyday lives, MSM on vacation may be especially prone to engage in higher rates of substance use. Over the course of approximately 3 days, more than half of the present sample reported drinking until they were intoxicated and a significant minority (16%) reported illicit substance use. PDE-5 inhibitors were used by a significant subset of the sample; these medications were the third most common substance used, eclipsed in popularity only by alcohol and marijuana. Men reporting Viagra, Levitra, or Cialis use had high rates of sexual risk behaviors and were likely to report using other substances. The association between Viagra use and sexual risk has led some investigators to suggest that Viagra should carry a warning label alerting users of this association.39 The pattern shown in this research suggests that Viagra and similar medications are being used much like any other recreational club drug. Some individuals may also be using these medications specifically to counteract the negative sexual effects of other substances such as alcohol. In addition to the sexual risks associated with use of these medications, men may also be at risk for adverse interactions between PDE-5 inhibitors and substances of abuse. For example, in the current study, men using medications for erectile dysfunction also commonly reported poppers use over a relatively short time period despite warnings that these substances can be dangerous when used together.

These findings suggest there is a particularly risky subgroup of MSM travelers that should be the focus of behavioral interventions. However, interventions directed at MSM travelers face many challenges. Most empirically validated HIV prevention approaches rely on ongoing contact with the individuals at risk, an approach not practical for use with travelers. Potential interventions for this population might include informational outreach, media campaigns, motivational enhancement messages, and social marketing campaigns. Successful HIV prevention interventions for MSM travelers will need to incorporate substance abuse reduction strategies. Educational efforts concerning the potential negative interactions between medications for erectile dysfunction and other substances also are warranted. Approaches also might elicit the assistance of individuals present in risk settings such as bartenders or resort workers to provide information and deliver prevention messages. Providing health information or motivational messages at opportune times such as when first checking into a hotel in the resort area may be beneficial. In addition, it may be possible to provide health information for some travelers before they arrive in the tourist area (e.g., if they have made travel arrangements through a gay-oriented travel agency, aboard a gay-oriented cruise ship, and so on). Any intervention techniques directed at this population should focus on the special characteristics of vacationers at risk.

Interventions designed to reduce risk in this population also need to recognize that many persons on vacation are seeking new experiences and are frequently hoping to find new romantic or sexual partners.7,8,40 Efforts to alter what may be the primary motivations for travel may engender resistance or resentment. In environments such as these, harm reduction approaches and interventions that take a nondirective, nonauthoritarian tone (e.g., motivational enhancement) may promote safety while remaining acceptable to the target population.41–43 Future research should examine the extent to which MSM are open to receiving prevention messages while on vacation. In addition, future studies should determine the best ways to reach those MSM travelers at highest risk, including individuals using PDE-5 inhibitors, alcohol, and other substances.


The current study collected data from a convenience sample in 2 tourist destinations popular among gay men. Generalization to all MSM travelers or travelers to other types of tourist areas may not be warranted. The study relied on self-reports of sexual behavior and substance use. Therefore, our methodology may have resulted in underreporting of these socially stigmatized behaviors. The cross-sectional design of the study also limits our ability to draw causal conclusions concerning associations among medications for sexual facilitation, substance use, and sexual risk behavior. Associations between substance use and sexual risk, although significant, accounted for modest amounts of variance. Future research should examine additional factors that may be associated with risk, including HIV prevention knowledge and attitudes toward sex on vacation. The current study was further limited by the necessity of brevity and the need to make paper questionnaires simple and understandable for self-administration. Future research should examine a number of factors not assessed in the current study, including motivations for travel, travel circumstances that may be related to sexual risk (e.g., whether men were traveling alone or with a partner), and differences in sexual risk behaviors between home and vacation environments.

One challenge facing this area of research is the difficulty in measuring the risk behaviors of MSM travelers when they are in their home communities to make meaningful comparisons with their behaviors in the tourist area. Whittier et al6 recruited MSM travelers and assessed their sexual behavior during their time in the resort community and for the previous 60 days spent in their home communities. Although a valuable first step, this methodology raises concerns because participants are recalling both recent (vacation) behaviors and more distant (home) behaviors. In addition, the assessment timeframes are not consistent across settings. Future research should attempt to assess behaviors in both settings using consistent assessment periods.

Despite the limitations, this study is one of the few investigations of substance use and sexual risk behavior among MSM vacationing in the United States. Participants in the current study traveled to Key West and Rehoboth Beach from around the United States and from several other countries. Many participants traveled from areas of low HIV prevalence to these high HIV prevalence locations. Individuals who are sexually active in multiple locations may unintentionally spread HIV to areas that were previously little affected by the disease. In this way, MSM travelers may be an epidemiologically important group that facilitates the dissemination of sexually transmitted infections from areas of high prevalence to areas of low prevalence. The current study reports initial evidence for the need to provide interventions for this population. In an era of limited budgets for prevention programs, interventions directed at substance-using MSM travelers may prove cost-effective in reducing the spread of HIV.


1. AIDS Epidemic Update: December 2002. Geneva: UNAIDS, 2003.
2. Centers for Disease Control and Prevention. Increases in unsafe sex, rectal gonorrhea among men who have sex with men: San Francisco, CA, 1994–1997. MMWR Morb Mortal Wkly Rep 1999; 35:773–777.
3. Rietmeijer CA, Patnaik JL, Judson FN, et al. Increases in gonorrhea and sexual risk behaviors among men who have sex with men: A 12-year trend analysis at the Denver metro health clinic. Sex Transm Dis 2003; 30:562–567.
4. Clift SM, Forrest SP. Factors associated with gay men’s sexual behaviours and risk on holiday. AIDS Care 1999; 11:281–95.
5. Benotsch EG, Mikytuck JM, Ragsdale K, et al. Sexual risk and HIV acquisition among MSM travelers to Key West, Florida: A mathematical modeling analysis. AIDS Pat Care STDs. In press.
6. Whittier DK, St. Lawrence JS, Seeley S. Sexual risk behavior of men who have sex with men: Comparison of behavior at home and at a gay resort. Arch Sex Behav 2005; 34:95–102.
7. Bellis MA, Hughes K, Thomson R, et al. Sexual behavior of young people in international tourist resorts. Sex Transm Infect 2004; 80:43–47.
8. Black P. Sex and travel: Making the links. In: Clift S, Carter S, eds. Tourism and Sex: Culture, Commerce and Coercion. London: Pinter Press, 2000:250–264.
9. McKercher B, Bauer TG. Conceptual framework of the nexus between tourism, romance, and sex. In: Bauer TG, McKercher B, eds. Sex and Tourism: Journeys of Romance, Love and Lust. New York: Haworth, 2003:3–17.
10. Kanigher S. Tourism bureaus say slogan deal unusual. Las Vegas Sun, July 7, 2005. Available at: Accessed August 2, 2005.
11. Apostolopoulos Y, Sönmez S, Yu CH. HIV-risk behaviors of American spring break vacationers: A case of situational disinhibition? Int J STD AIDS 2003; 13:733–743.
12. Bellis MA, Hughes K, Lowey H. Healthy nightclubs and recreational substance use from a harm minimization to a healthy settings approach. Addict Behav 2002; 27:1025–1035.
13. Egan CE. Sexual behaviours, condom use and factors influencing casual sex among backpackers and other young international travelers. Can J Hum Sex 2001; 10:41–58.
14. Eiser JR, Ford N. Sexual relationships on holiday: A case of situational disinhibition? J Soc Pers Rel 1995; 12:323–339.
15. Elliot L, Morrison A, Ditton J, et al. Alcohol, drug use and sexual behaviour of young adults on a Mediterranean dance holiday. Addict Res 1998; 6:319–340.
16. Maticka-Tyndale E, Herold ES, Oppermann M. Casual sex among Australian schoolies. J Sex Res 2003; 40:158–169.
17. Mewhinney DM, Herold ES, Maticka-Tyndale E. Sexual scripts and risk-taking of Canadian university students on spring break in Daytona Beach, Florida. Can J Hum Sex 1995; 4:273–288.
18. Rogstad KE. Sex, sun, sea, and STIs: Sexually transmitted infections acquired on holiday. BMJ 2004; 329:214–217.
19. Wright ER. Travel, tourism, and HIV risk among older adults. J Acquir Immun Defic Syndr 2003; 33:S233–S237.
20. Crosby R, DiClemente RJ, Mettey A. Correlates of recent unprotected anal sex among men having sex with men attending a large sex resort in the south. Sex Transm Dis 2003; 30:909–913.
21. Kalichman SC, Gore-Felton C, Benotsch EG, et al. Trauma symptoms, sexual behaviors, and substance abuse: Correlates of childhood sexual abuse and HIV risks among men who have sex with men. J Child Sex Abus 2004; 13:1–15.
22. Leigh BC, Stall R. Substance use and risky sexual behavior for exposure to HIV: Issues in methodology, interpretation, and prevention. Am Psychol 1993; 48:1035–1045.
23. Mansergh G, Colfax GN, Marks G, et al. The circuit party men’s health survey: Findings and implications for gay and bisexual men. Am J Public Health 2001; 91:953–958.
24. Purcell DW, Parsons JW, Halkitis PN, et al. Substance use and sexual risk behavior among HIV-positive men who have sex with men. J Subst Abuse 2001; 13:185–200.
25. Benotsch EG, Kalichman SC, Kelly JA. Sexual compulsivity and substance use in HIV seropositive men who have sex with men: Prevalence and predictors of high-risk behaviors. Addict Behav 1999; 24:857–868.
26. Halkitis PN, Parsons JT, Stirrat MJ. A double epidemic: Crystal methamphetamine drug use in relation to HIV transmission among gay men. J Homosex 2001; 41:17–35.
27. Hirshfield S, Remien RH, Humberstone M, et al. Substance use and high-risk sex among men who have sex with men: A national online study in the USA. AIDS Care 2004; 16:1036–1047.
28. Mattison AM, Ross MW, Wolfson T, et al. Circuit party attendance, club drug use, and unsafe sex in gay men. J Subst Abuse 2001; 13:119–126.
29. Parsons JW, Vicioso K, Kutnick A, et al. Alcohol use and stigmatized sexual practices of HIV seropositive gay and bisexual men. Addict Behav 2004; 29:1045–1051.
30. Kim AA, Kent CK, Klausner JD. Increased risk of HIV and sexually transmitted disease transmission among gay or bisexual men who use Viagra, San Francisco, 2000–2001. AIDS 2002; 16:1425–1428.
31. Benotsch EG, Kalichman S, Cage M. Men who have met sex partners via the Internet: Prevalence, predictors, and implications for HIV prevention. Arch Sex Behav 2002; 31:177–183.
32. Chu PL, McFarland W, Gibson S, et al. Viagra use in a community-recruited sample of men who have sex with men, San Francisco. J Acquir Immun Defic Syndr 2003; 33:191–193.
33. Sherr L, Bolding G, Maguire M, et al. Viagra use and sexual risk behaviour among gay men in London. AIDS 2000; 14:2051–2053.
34. Crosby R, DiClemente RJ. Use of recreational Viagra use among men having sex with men. Sex Transm Infect 2004; 80:466–468.
35. Rosen RC, McKenna KE. PDE-5 inhibition and sexual response: Pharmacological mechanisms and clinical outcomes. Annu Rev Sex Res 2002; 13:36–88.
36. Centers for Disease Control and Prevention. Cases of HIV infection and AIDS in the United States, 2003. HIV AIDS Surveill Rep 2004; 15. Available at: Accessed August 5, 2005.
37. Hays WL Statistics, 4th ed. Fort Worth: Holt, Rinehart, and Winston, 1988.
38. Kleinbaum DG. Logistic Regression. New York: Springer-Verlag, 1994.
39. San Francisco asks FDA to place STD warning on Viagra. AIDS Policy Law 2002; 17:8.
40. Benotsch EG, Nettles CD, Wong F, et al. Sexual risk behavior in men attending Mardi Gras celebrations in New Orleans, Louisiana. Poster presented at the 27th annual meeting of the Society of Behavioral Medicine, San Francisco, CA, March 2006.
41. Kippax S, Noble J, Prestage G, et al. Sexual negotiation in the AIDS era: Negotiated safety revisited. AIDS 1997; 11:191–197.
42. Davidovich U, de Wit JBF, Stroebe W. Behavioral and cognitive barriers to safer sex between men in steady relationships: Implications for prevention strategies. AIDS Educ Prev 2004; 16:304–314.
43. Kalichman S, Cain, D, Weinhardt, et al. Experimental components analysis of brief theory-based HIV/AIDS risk-reduction counseling for sexually transmitted infection patients. Health Psychol 2005; 24:198–208.
© Copyright 2006 American Sexually Transmitted Diseases Association