Dysfunctional arousal

Psychogenic dysfunction occurs if a patient does not respond to psychic arousal. It occurs in up to 30% of all cases of ED. Common causes include performance anxiety, strained relationships, lack of sexual arousability, and overt psychiatric disorders such as depression and schizophrenia.5 It is postulated that the anxious or nervous man will have excessive stimulation of the sympathetic system, leading to smooth muscle contraction of arterioles and vascular spaces within erectile tissue.6 O Many patients may initially have organic dysfunction, but develop a psychogenic component as they try to cope with their inability to achieve an erection. It has been estimated that up to 80% of ED cases have an organic cause, with many having a psychogenic component as well.1... 

Later, in his safety update of the NDA on October 17, 1986, Kapit spoke of several cases of a syndrome of fluoxetine-induced hyper-arousal and excessive stimulation... [that] resemble episodes of stimulant drug intoxication. It was especially likely to occur at higher doses, but it could occur at the standard 20 mgs. The state of overstimulation included anxiety, agitation, insomnia, headache, confusion, dizziness, obnubilation [mental clouding], memory dysfunction, tremor, impaired motor coordination. Hyperactivity, hypomania, and mania may sometimes occur. In overdose, the drug produces an even more flagrant stimulant syndrome culminating in seizures. Thus there is a continuum of stimulation effects. 

Erectile dysfunction. Sildenafil, vardenafii, and tardalafil are inhibitors of PDE-5 and are used to promote erection. During sexual arousal NO is released from nerve endings in the corpus cavernosum of the penis, which stimulates the formation of cGMP in vascular smooth muscle. PDE-5, which is important in this tissue, breaks down cGMP, thus counteracting erection. Blockers of PDE-5 "conserve cGMP. 

The adverse sexual effects of SSRIs have been reviewed (58). The use of SSRIs is most often associated with delayed ejaculation and absent or delayed orgasm, but reduced desire and arousal have also been reported. Estimates of the prevalence of sexual dysfunction with SSRIs vary from a small percentage to over 80%. Prospective studies that enquire specifically about sexual function have reported the highest figures. Similar sexual disturbances are seen in patients taking SSRIs for the treatment of anxiety disorders (59), showing that SSRI-induced sexual dysfunction is not limited to patients with depression. It is not clear whether the relative incidence of sexual dysfunction differs between the SSRIs, but it is possible that paroxetine carries the highest risk (58). 

A 36-year-old man took amfebutamone 150 mg/day as part of a smoking cessation program and soon complained of complete anorgasmia sexual desire and arousal were preserved (26). Amfebutamone was withdrawn and the sexual dysfunction resolved within 3 days. 

Despite occasional reports of reduced libido and erectile dysfunction, lithium causes little in the way of sexual dysfunction in men or women (425). In a brief review of the sexual adverse effects of psychotropic drugs, reduced libido and arousal with lithium were mentioned in passing, particularly when it was combined with other drugs (which, of course, makes it difficult to implicate lithium) (426). 

BZs should be reserved for patients at low risk of substance abuse, those who require rapid relief, or those who have not responded to other therapies. Clonazepam is the most extensively studied BZ for treatment of generalized SAD. It improved fear and phobic avoidance, interpersonal sensitivity, fears of negative evaluation, and disability measures. Adverse effects include sexual dysfunction, unsteadiness, dizziness, and poor concentration. Clonazepam should be tapered at a rate not to exceed 0.25 mg every 2 weeks. Gabapentin was effective for SAD, and onset of effect was 2 to 4 weeks. j8-Blockers blunt the peripheral autonomic symptoms of arousal (e.g., rapid heart rate, sweating, blushing, and tremor) and are often used to decrease anxiety in performance-related situations. For specific SAD, 10 to 80 mg of propranolol or 25 to 100 mg of atenolol can be taken 1 hour before the performance. A test dose should be taken at home on a day before the performance to be sure adverse effects wUl not be problematic. Incomplete response to a first-line agent may benefit from augmentation with buspirone or clonazepam. 

A 49-year-old man with Parkinson s disease was treated with ropinirole, and the dosage eventually reaching 3 mg tds. He had penile erections 20-30 minutes after each dose, lasting for 10-15 minutes. They were not associated with arousal and were very uncomfortable he had no history of sexual dysfunction. Their frequency diminished with a reduction in drug dosage, but they stopped completely only on drug withdrawal. 

Serotonin reuptake inhibitors (SSRI). Five SSRI antidepressant drugs have been included in at least one placebo-controlled randomized clinical trial in BED, with variable effect (see below). Side effects are similar for all SSRI. These include gastro-intestinal symptoms, such as nausea and diarrhea sexual dysfunction a heightened sense of arousal. 

In humans, nicotine is reported to increase arousal and attention as well as decrease reaction time and prevent decline in efficiency over time (Wesnes and Warburton, 1983, 1985). In both animals and humans nicotine improves the subject s ability to withhold responses to inappropriate stimuli (Myrsten et al., 1972 Wesnes and War-burton, 1983 Newhouse et al., 1988). This may be relevant to AD because a cardinal feature of the cognitive disorder of AD and a possible marker of cholinergic dysfunction (Fuld et al., 1982) is the difficulty demented patients have in inhibiting inappropriate responses or in responding to inappropriate stimuli. This difficulty in response selection and/or suppression is one explanation of the liberal response bias seen in AD. Gray et al. (1996) have shown that nicotine enhances hippocampal synaptic transmission which may be critical for new learning to take place. 

Nonhormonal strategies also are available to treat female sexual arousal disorder. A transdermal formulation of alprostadil, used to treat male erectile dysfunction, has been shown to improve the arousal success rate. Applied 15 minutes before intercourse, this cream can cause local irritation, which is reversible on cleansing (115). 

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