Most readily accessible over-the-counter dietary supplements sold to improve male sexual health are largely ineffective and unsafe if taken without the guidance of trained physician, warns a new study.
"While certain natural supplements we reviewed show promise for improving mild sexual dysfunction, they lack robust human evidence," said study senior author Ryan Terlecki, associate professor of urology at the Wake Forest Baptist Medical Center in Winston-Salem, North Carolina, US.
For some products, there is no scientific evidence to support claims that can positively impact erectile function, libido and sexual performance.
And some products that are advertised as being "natural," contain traces of phosphodiesterase-5-inhibitors (PDE5Is), the same class of medication that includes prescription drugs such as Viagra, used to treat erectile dysfunction.
"Men who use these medications without a physician's supervision run the risk of taking them inappropriately. Patients with advanced heart disease, for example, or who take nitrates, such as nitroglycerin, should not use PDE5Is as it may cause an unsafe drop in blood pressure," Terlecki said.
It has been found that nearly 80 percent of tested samples of over-the-counter products purchased in the US and Asia contained PDE5Is.
"Likewise, men with severe liver impairment or end-stage kidney disease requiring dialysis should avoid these products," Terlecki pointed out.
In addition, Terlecki said, men with enlarged prostates who take medications such as Flomax (tamsulosin), terazosin or doxazosin need to know how to time the dosing of the two medications to avoid causing dizziness and potential falls, which may result in fractures.
An estimated 40 to 70 percent of men experience some form of sexual dysfunction during their lives. Due to concern regarding costs of prescription drugs, or embarrassment over discussing sexual concerns with their physicians, some men turn to over-the-counter products.
"We reviewed the current evidence available for each of the ingredients in top-selling men's health products to provide urologists with a guide they could use to counsel their patients," Terlecki said.
"Patients are paying more than $5 per day to take products with no proven effectiveness," he noted.
The results were published online in the Journal of Sexual Medicine.
