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Paroxetine Treatment of Problematic Pornography Use: A Case Series

Background How best to conceptualize problematic pornography use (PPU) and intervene most effectively remain debated, with obsessive–compulsive disorder (OCD) and addiction frameworks. We investigated the efficacy of the serotonin-reuptake inhibitor paroxetine in combination with cognitive-behavioral therapy in the treatment of problematic pornography use (PPU). Case presentation Three heterosexual males with PPU were treated with cognitive-behavioral therapy and paroxetine. Frequency of pornography use, other sexual behaviors, and anxiety were assessed during treatment. Discussion Paroxetine treatment, although seemingly initially effective in reducing pornography use and anxiety, appeared related to new compulsive sexual behaviors after 3 months. Conclusions Paroxetine may hold promise for short-term reduction of PPU and related anxiety, but new potentially distressing sexual behaviors may emerge. The cases suggest that PPU may arise from multiple domains. We propose an explanation of the effects based on recent neuroscientific research on sexual behaviors and alcohol use.


CASE REPORTS
Patients were Caucasian, heterosexual males [measured with the Polish adaptation of Kinsey's Sexual Orientation Scale (Wierzba et al., 2015)] seeking treatment for PPU accompanied by compulsive masturbation (characteristics in Table 1). None took medication, had significant medical problems or histories of risky sexual behaviors, use of paid sexual services or affairs. All reported some risky alcohol drinking. Two had episodes of depressive disorder at ages 18 (Mr. A) and 24 (Mr. C) years, respectively. All reported preoccupations/urges, numerous failed quit attempts, and significant distress related to PPU and masturbation.
Patients attended cognitive-behavioral therapy delivered by doctoral-level clinical psychologists and completed selfmonitoring reports of pornography consumption (daily) and anxiety (weekly; Figure 1).
All patients were asked about sexual dysfunction related to the medication and reported decreased libido and delayed ejaculation during the initial 2-4 weeks of paroxetine intake (20 mg/day). Within 10 weeks from the onset of paroxetine treatment, reported libido was close to the normal and patients A and B did not experience any difficulties in erection or ejaculation during sexual activity with their partners or during solitary sexual activity (patient C had only solitary sexual activity and also did not report experiencing any troubles). Within the 10 weeks of paroxetine intake, all patients also experienced significant decreases in self-reported anxiety [A: 45%; B: 50%; C: 49%; M before = 7.03; SD = .38; M after = 3.66; SD = .4; t(2) = 90.7; and p < .001]. Similarly, frequency of pornography consumption decreased, albeit not to a statistically significant level [A: 80%; B: 69%; C: 52%; M before = 7.57; SD = 2.46; M after = 2.25; SD = .28; t(2) = 3.78; and p = .078]. Interestingly, within 12-14 weeks, new sexual behaviors appeared. Patients A and C started engaging in paid sexual relations (up to three times a week), and patient B initiated an extra-marital affair (with his children's care provider). After 13 weeks of treatment, patient C went on vacation during which he engaged in an almost 2-weeklong paid sexual relationship and quit medication. Due to those new behaviors, all patients were evaluated for mania/ hypomania according to the criteria presented by Basco and Rush (2005). Patients A and B were assessed for symptoms of mania for three consecutive weeks and patient C for two consecutive weeks. None of the patients met criteria for mania or hypomania. Interestingly, all of the new sexual behaviors had a dyadic characteristic and were not accompanied with rebound of pornography use and masturbation.
The appearance of new sexual behaviors was discussed with patients during the meetings. Patient C reported the use of paid sexual services as having ego-syntonic elements. In his words, a vacation with paid "girlfriend-like-experiences" was one of the best times of his life. Patient C declared that he always preferred dyadic sexual activity over solitary activity, but due to high anxiety level and difficulties in creating intimate relationships with women, he was more prone to use pornography and masturbate. Patients A and B had very strong religious-based beliefs that extra-marital sexual relationships are morally reprehensible. In the case of patient A, his first use of paid sexual services was described as having a mixture of pride and guilt. Patient A described that he always wanted to have sexual experience with prostitute but was afraid to try. He also wanted to see what it was like to have sex with another person other than his girlfriend (who was his first sexual partner). His guilt was related to feeling that he was cheating on his girlfriend in a manner not consonant with his religious beliefs. A mixture of pride regarding sexual initiation and engagement and guilt related to a mismatch of this behavior with his religious beliefs was present during his sexual encounters. Patient B also described his extra-marital affair as being characterized by feelings of both pride and guilt. As in the case of patient A, his wife had been his first and only sexual partner (with the sexual initiation age of 20 years), and the drive for the affair involved fascination and a desire "to try something new." As patients A and B perceived the new behaviors as being contrary to their beliefs, yet nonetheless reported strong motivations to continue the behaviors, paroxetine treatment was stopped. In the following weeks, Mr. B reported ending his extra-marital relations, while Mr. A and Mr. C continued engaging in paid sexual services (about once a week). None of the patients were interested to increase the amounts of pornography use and frequency of masturbation (instead of the use of paid sexual services), as they were describing the pornography use as isolating, time

DISCUSSION AND CONCLUSIONS
These cases highlight several important points. In the 1990s, Dr. Coleman proposed that compulsive sexual behaviors may be driven by anxiety-reduction mechanisms (Coleman, 1991 (Coleman, 1991(Coleman, , 2015, PPU may arise from multiple domains (e.g., with anxious and rewardrelated/impulsive components), and paroxetine treatment may target only anxiety-related aspects. Our data do not provide convincing support for the first three possibilities. Frequently endorsed symptoms of hypomania, such as unusually high energy, decreased need for sleep, increased goal-directed activity, grandiosity, or expansive mood were not observed (Fiedorowicz et al., 2011). The new sexual behaviors had a dyadic characteristic and were not accompanied by rebound of PPU and solitary sexual activity, thus not providing strong support for the second possibility, although it cannot be completely excluded. If patients were pursuing more risky or arousing sexual behavior to overcome sexual dysfunction, we might anticipate increases in time spent viewing pornography and masturbating and new content of pornography being viewed within the first weeks of paroxetine treatment. We did not observe these patterns. Furthermore, prior to the emergence of new problematic sexual behaviors, patients were reporting the return of normal sexual functioning, suggesting that the new behaviors were not compensatory to sexual dysfunction. A possibility that fits with the data and warrants additional study relates to a theory described elsewhere  in response to a recent research by Nikolova et al. on risky alcohol drinking (Nikolova, Knodt, Radtke, & Hariri, 2015) and Victor et al. on risky sexual behaviors (Victor et al., 2015). Both theories propose that imbalances in ventral-striatum-related reward reactivity and amygdala-related threat reactivity may promote problematicalcohol drinking (Nikolova et al., 2015) or sexual risk taking Victor et al., 2015). Problematic behaviors may result from increased impulsivity (related to ventral-striatum-related reward reactivity) or increased anxiety (related to amygdala-related threat reactivity). Previous studies show that anxiety may be diminished with paroxetine, which has been linked to reductions in amygdala's volume (Szeszko et al., 2004), while other medications such as naltrexone may reduce reward responsivity (e.g., craving) and impulsivity (Bostwick & Bucci, 2008;Raymond, Grant, & Coleman, 2010;Kraus, Meshberg-Cohen, Martino, Quinones, & Potenza, 2015). Therefore, we hypothesize that in PPU, both of the above-mentioned mechanisms may operate, and this possibility warrants additional investigation. Although currently speculative, we may explain the observations in this case series as follows. All three patients had an initially high level of anxiety (as presented in Figure 1) and PPU may have helped them regulate their anxiety. Paroxetine may have helped to decrease amygdalarelated reactivity, resulting in decreased anxiety and subsequently decreased PPU. However, at some point, without targeting craving or reward-related processes, new compulsive sexual behaviors may have emerged in the setting of diminished anxiety. While such mechanisms appear to have support from experimental studies on sexual behaviors and problematic alcohol use Nikolova et al., 2015;Victor et al., 2015), they deserve further investigation in PPU. We are aware that there exists a big leap from three cases to neuronal mechanisms; however, at the level of symptoms, the accounts of these three individuals suggest that anxiety, and reward-related processes may both warrant strong consideration in the treatment of PPU and perhaps other compulsive sexual behaviors. Therefore, future clinical trials should consider combinations of paroxetine and naltrexone with careful assessment of sexual behaviors and individual-difference measures (e.g., impulsivity and anxiety) that may relate to treatment outcome. Authors' contribution: MG worked with patients, collected clinical data, and performed the statistical analysis. MG and MP analyzed the findings, interpreted them, and wrote the manuscript.

Conflict of interest:
The authors report no conflict of interest with respect to the content of this manuscript. Dr. M. N. Potenza has consulted for and advised Ironwood, Lundbeck, INSYS, Shire, RiverMend Health, and Opiant/ Lakelight Therapeutics; has received research support from Mohegan Sun Casino, the National Center for Responsible Gaming, and Pfizer; has participated in surveys, mailings, or telephone consultations related to drug addiction, impulsecontrol disorders, or other health topics; has consulted for gambling and legal entities on issues related to impulsecontrol and addictive disorders; provides clinical care in the Connecticut Department of Mental Health and Addiction Services Problem Gambling Services Program; has performed grant reviews for the National Institutes of Health and other agencies; has edited journals or journal sections; has given academic lectures in grand rounds, CME events and other clinical or scientific venues; and has generated books or book chapters for publishers of mental health texts.