Treatment of ED with exogenous testosterone replacement is indicated only for men with hypogonadism. By replacing endogenous concentrations of testosterone, androgen receptors are stimulated to maintain libido. ED is not corrected directly through use of testosterone replacement therapies. Testosterone is available in multiple formulations, including tablets, gels, intramuscular injections, and scrotal and dermal patches, allowing treatment to be tailored to meet the needs of the patient. Before using testosterone, men should undergo screening for BPH and prostate cancer, as androgen therapies can worsen these conditions. The adverse effects of testosterone therapy (e.g., weight gain, acne, exacerbation of hypertension, gynecomastia, edema) are numerous and common.5 Apomorphine (Uprima) is a dopamine receptor agonist that works to increase erections through stimulation of dopamine2 receptors in the hypothalamus and the limbic system. Five percent to 15% of patients treated with subcutaneous apomorphine for Parkinson's disease experienced frequent erections, spurring further study of a sublingual (SL) formulation not yet FDA approved for ED treatment. Studies have demonstrated that 2 to 3 mg of apomorphine SL is most effective in treating ED, and higher doses show no additional effects. Apomorphine SL has an onset of action of approximately 18 to 20 minutes. The most common adverse effect reported is nausea.19 Yohimbine is an alpha2 -adrenergic antagonist that increases catecholamines to ultimately improve mood. Its proerectogenic properties are believed to allow vasodilatation. Current clinical trials assessing the effects of yohimbine involve small study populations and a short duration of therapy. Increases in blood pressure and heart rate, anxiety, palpitations, and tremors are adverse effects associated with yohimbine. Papaverine is a smooth muscle relaxant that is often used in combination with phentolamine, an alpha1 -adrenergic antagonist, making smaller doses of each individual component necessary to achieve therapeutic effects. Smaller doses of these agents minimize adverse effects, which include hypotension, hepatotoxicity, and priapism.5,14 Ginseng is often classified as an adaptogen, or an herb that increases resistance to environmental stressors. It is believed to improve stamina and perhaps sexual function. However, data supporting the use of ginseng to treat sexual impairment are limited. Ginseng may cause increased blood pressure, headache, insomnia, pruritus, increased bleeding, and gastrointestinal upset.20,21 The success rate with penile prostheses has been reported to be as high as 98%. However, these devices must be carefully inserted by a urologist during surgery that typically requires general anesthesia. Infection is the most common adverse effect experienced in the acute period following surgery. Patients are still prone to late-onset infections and mechanical failure, although the current five-year failure rate for inflatable prostheses ranges from 6% to 16%, due to improved technology. Insertion of a penile prosthesis is an expensive procedure that may cause irreversible damage to the penis due to its invasive nature. Therefore, it is often considered a last option for patients with ED.1,5,8 Some patients with ED may be managed through vascular surgery. American Urological Association recommendations recognize arterial reconstructive surgery as an option for patients who have an arterial occlusion with no evidence of generalized vascular disease. Similar to insertion of penile prostheses, vascular surgery carries a risk for infection and damage to the penile tissue.1 Health care providers should assist patients in weighing the risks and benefits associated with the surgical management of ED.
A study published in the January 2016 edition of the American Journal of Clinical Nutrition suggests a diet rich in flavonoid-rich foods can reduce the risk of ED. The study reviewed data from more 25,000 men who were middle-aged and older, and who participated in routine health survey since 1986. Researchers compared responses about having and maintaining an erection sufficient for intercourse with the number of flavonoid-rich foods each man reported consuming. Men who ate more fruit had a 14 percent reduced risk of ED. Men who consumed a high volume of flavonoid-rich fruits and exercised regularly experienced a 21 percent reduction of risk. Foods such as blueberries, cherries, blackberries, radishes, citrus fruits, and red wine offered the flavonoid profile with the greatest benefits. L-arginine is an amino acid that naturally occurs in the body and helps synthesize proteins. It is also the precursor to the compound nitric oxide (NO). NO is vital for achieving and maintaining an erection, as it helps the blood vessels relax to support blood flow throughout the body, including into the penis. Supplementing arginine in conjunction with a balanced lifestyle can offer men added support for a healthy erection. Added pounds can have a significant impact on blood flow, as well as put men at risk for diseases that may exacerbate ED. A study published in the January 2005 issue of the journal Canadian Family Physician found 30 percent of men who participated in a weight loss program and lost an average of 15 percent of their total body weight saw sexual function restored compared to only 5 percent of the control group.
