June 1996, Vol. XIII ,Issue 6
Paraphilias as defined by DSM-IV, are sexual impulse disorders characterized by intensely arousing, recurrent sexual fantasies, urges and behaviors (of at least six months' duration) that are considered deviant with respect to cultural norms and that produce clinically significant distress or impairment in social, occupational or other important areas of psychosocial functioning. The common paraphilias described include exhibitionism (exposure of genitals to a stranger), pedophilia (sexual activity with a prepubescent child, generally 13 years of age or younger), voyeurism (observing others' sexual activities), fetishism (use of inert objects, such as female undergarments), transvestic fetishism (cross-dressing), sexual sadism (inflicting suffering or humiliation), sexual masochism (being humiliated, beaten, bound or made to suffer) and frotteurism (touching, rubbing against a nonconsenting person).
Although several of these disorders can be associated with aggression or harm, others are neither inherently violent nor aggressive (e.g., fetishism, transvestic fetishism).
Paraphilias are predominantly male sexuality disorders with an estimated sex differences ratio of 20:1 in sexual masochism. (The other paraphilias are almost never diagnosed in females, although some cases have been reported-Ed.)
There is a second group of sexual impulse disorders not currently classified as paraphilias because the particular sexual behaviors affected are not considered "deviant" with respect to contemporary cultural norms. I have proposed to designate these disorders as paraphilia-related disorders (Kafka 1994a) based on the following clinical data:
- The boundary for social as well as sexual deviance is largely determined by cultural and historical context. As such, sexual disorders once considered paraphilias (e.g., homosexuality) are now regarded as variants of normal sexuality; so too, sexual behaviors currently considered normal (e.g., masturbation) were once culturally proscribed.
- Paraphilia-related disorders have been diagnosed in male paraphiliacs (Longo and Groth; Langevin and others), and men selected for studies of paraphilia-related disorders are reported to have paraphilias as well (Carnes).
- Paraphilia-related disorders can produce a pattern of sexual frequency and intensity with concomitant psychosocial impairment that does not readily distinguish them from nonviolent paraphilic disorders (Carnes, Kafka and Prentky 1992a).
- Analogous with paraphilias, the presence of a single paraphilia-related disorder increases the likelihood of occurrence of a multiplicity of these behaviors in an affected person.
- Paraphilias and paraphilia-related disorders can both be ameliorated by antiandrogens and serotonergic antidepressants, especially serotonin reuptake inhibitors. Disorders of sexual impulsivity can be pleomorphic and may include sexual arousal to behaviors that are socially deviant as well as normal. In fact, inasmuch as paraphilia-related disorders may be common in paraphiliacs and also occur without the companion of the latter, paraphilia-related disorders may be the more prevalent form of sexual impulsivity. In addition, although the estimated sex difference ratio for paraphilia-related disorders is unknown, protracted promiscuity (e.g., "nymphomania") and compulsive masturbation are not uncommon behaviors described by women.
Although this article is written to highlight pharmacotherapy, most males with sexual impulsivity disorders treated with pharmacotherapy should have a concurrent psychological treatment including such modalities as a specialized sex offender program, group therapy, a 12-step "sexual addiction/compulsion" recovery program or a therapist familiar with this complex's disorders.
While there is no single unifying theory to adequately explain the pathogenesis of sexual impulse disorders, there are currently two distinct classes of psychopharmacological agents, antiandrogens and serotonergic antidepressants, that are prescribed during the treatment of paraphilias and paraphilia-related disorders.
The antiandrogens cyproterone acetate (CPA) and medroxyprogesterone acetate (MPA [Amen, Depo-Provera) are the most commonly prescribed agents for the control of repetitive deviant sexual behaviors and have been prescribed for paraphilia-related disorders as well. Although neither drug has been specifically approved by the Food and Drug Administration for the treatment of paraphilic disorders, both agents are used in Canada and Europe and medroxyprogesterone is available in the United States. Both agents, available as oral or parenteral preparations, have been shown in multiple studies to reduce recidivism rates in male sexual aggressors (for review, Bradford 1995a), the group most commonly prescribed these drugs.
Common side effects of antiandrogens include weight gain, fatigue, hypertension, headaches, hyperglycemia, leg cramps and diminished spermatogenesis. In addition, there may be an increased risk of thromboembolism in men (and women) with risk factors associated with clotting disorders and rare feminization effects such as breast swelling and changes in hair distribution during prolonged treatment.
Medroxyprogesterone acetate, an analog of progesterone, lowers serum testosterone by reducing the production of testosterone from its precursors, and by significantly increasing its metabolic clearance rate from serum by interfering with the binding of testosterone to a serum sex-hormone binding globulin. It is most commonly prescribed in the parenteral depot form and injected weekly or biweekly in doses ranging from 100 to 800 mg (usually 200 to 500 mg). Although less clinical data exist on oral medroxyprogest-erone, encouraging results have been reported (Gottesman and Schubert) using doses from 20 to 100 mg per day.
Cyproterone acetate inhibits testosterone directly at androgen receptor sites and also exhibits antigonadotrophic effects. In its oral form, the usual prescribed dosage range is 50 to 200 mg per day. Parenterally, it is usually administered every one to two weeks at dosages of 300 to 600 mg per injection.
Testosterone, the principal androgen (sex hormone) produced by the testes, is considered the most important androgen affecting male sexual behavior. The role of testosterone as a primary etiological factor in physical and sexual aggression in men, however, remains ambiguous. The majority of studies of testosterone in male sex offenders reveal that serum total testosterone (i.e., protein bound and unbound) is within normal limits in all but a subgroup of the most violent paraphiliacs (Hucker and Bain). In fact, there are reports of male paraphilias with low baseline serum testosterone (Seim and Dwyer). Despite these data, most men prescribed antiandrogens report a calming effect in both sexual aggression and general irritability, and these agents have become the standard biological intervention for sexually aggressive paraphiliacs. Since the prescription of antiandrogens for paraphilias is still considered an off-label use (i.e., not FDA-approved for that specific use), it is prudent to document informed consent in a patient's record before antiandrogen administration, and to obtain baseline fasting glucose, liver functions, vital signs, serum FSH and total testosterone.
The effect of antiandrogens on sexual desire and associated fantasies, erections, urges and other sexual behaviors is usually evident by two to four weeks after the initiation of pharmacotherapy. Pharmacological tolerance to their effects has not been described, and either agent can be tapered without a rebound increase in sexual or aggressive behaviors. After a period of symptom stabilization, a lower maintenance dose can sometimes be titrated to minimize side effects, and in some cases, to permit a more selective mitigation of deviant sexuality in comparison with conventional sexual desire.
Sexual fantasies and erections usually return approximately two to four weeks after an antiandrogen is gradually tapered, although in some men it may take longer for the effects to be fully reversed.
Although there may not be a linear relationship between lowered serum testosterone and diminished deviant sexual behavior, some investigators seek to lower serum testosterone to prepubertal levels (100 ng per dL) and others target a 50-percent reduction of circulating testosterone as adequate for a therapeutic effect with less side effects. This clinical feature of monitoring circulating testosterone as well as the parenteral administration of these agents provides a means to assure compliance in men who are court-mandated, are sexual predators or are incapable of taking oral medications reliably to assure that compliance with treatment had been maintained should an offense reoccur. On the other hand, oral MPA or CPA can be utilized with highly motivated males with paraphilias and paraphilia-related disorders (Gottesman and Schubert).
In oral preparation, the daily dose of antiandrogens can be more readily titrated to perhaps preserve "conventional"sexual arousal. Compliance is enhanced because the patient is afforded improved self-efficacy, and the dose can be more easily adjusted during a slow taper phase.
It is common practice that antiandrogen pharmacotherapy is utilized as a therapeutic modality early (e.g., three to 12 months) during cognitive, behavioral and group therapies in the treatment of sex offender paraphiliac patients. In some circumstances, however, antiandrogens have been prescribed for more than a decade with no significant untoward effects and with continued beneficial mitigation of deviant sexual arousal.