Sexual dysfunction duloxetine

The recent approval of the SNRI duloxetine for the treatment of diabetic neuropathy reinforces the utility of this drug class in the treatment of neuropathic pain. Other largely untapped areas which remain to be exploited with this drug class include sexual dysfunction, such as premature ejaculation, irritable bowel syndrome, obesity, neurodegenerative diseases such as Parkinson s disease, restless leg syndrome, and substance abuse and addiction. It is apparent that considerable opportunities for drug discovery will exist in this area for some time to come. 

Regarding side-effect profiles, all three SSNRIs are generally well tolerated, most adverse events occurring early in treatment, with a mild to moderate severity and a tendency to decrease or disappear with continued treatment. Venlafaxine (1) seems to be the least weU-toIerated SNRI, combining a higher level of serotonergic adverse events (nausea, sexual dysfunction, withdrawal problems) with dose-dependent hypertension. In contrast, milnacipran (2) and duloxetine (3) appear better tolerated and essentially devoid of cardiovascular toxicity. 

Side effects, mainly due to serotonin reuptake inhibition include G1 upset, nervousness, and sexual dysfunction. SSRls are associated with an increased risk of falls. Hyponatraemia due to SIADH is an uncommon, but important side effect in elderly patients. Selective serotonin and norepinephrine reuptake inhibitors (S SNRls) such as venlafaxine and duloxetine are also useful in older patients. Other heterocyclic antidepressants of importance in older patients because of relative safety include bupro-prion and mirtazepine. They are reserved for patients with resistance to or intolerance of SSRls. Currently, trazodone is used mostly for sleep disturbance in depression in doses of 50-100 mg at bedtime. The monoamine oxidase inhibitors phenelzine. 

Sexual dysfunction. The controlled clinical trials of duloxetine in the treatment of major depression used a rating scale to assess prospectively treatment-emergent sexual dysfunction. As with... 

SSRIs and venlafaxine, males who received duloxetine experienced more difficulty with ability to reach orgasm than did males who received placebo. However, females did not experience more sexual dysfunction while taking duloxetine than did those taking placebo. The reason for fewer sexual side effects in females is not clear, and some females will experience treatment-emergent anorgasmia or decreased libido. 

Duloxetine has recently been marketed as an antidepressant in Europe. It inhibits the re-uptake of serotonin and noradrenaline, with minimal effects on other neurotransmitter mechanisms. It is therefore classified as a serotonin and noradrenaline re-uptake inhibitor (SNRI) and is grouped with venlafaxine. The adverse effect profile of duloxetine appears to be similar to that of the SSRIs and venlafaxine. In placebo-controlled trials the most common adverse effects were nausea (37%), dry mouth (32%), dizziness (22%), somnolence (20%), insomnia (20%), and diarrhea (14%). Sexual dysfunction has also been reported. Current data suggest that, unlike venlafaxine, duloxetine does not increase the blood pressure, but further post-marketing surveillance studies will be needed to confirm this (1). 

In a study on the effects of maca for sexual dysfunction induced by selective serotonin reuptake inhibitors (SSRI), patients who were stable on an SSRI (patients were taking escitalopram, citalopram, sertraline, venlafexine, fluoxetine, paroxetine, duloxetine, or fluvoxamine) were orally administered 1.5 or 3 g of maca daily for 12 weeks. No adverse effects of maca, including effects on SSRI efficacy, were reported, and patients in the high dose group had a modest improvement in depression (Dording et al. 2008). 

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