Erectile dysfunction. We’ve all heard of it. And Pfizer’s advertising campaign when it introduced its blockbuster erectile dysfunction drug Viagra (sildenafil) made it a household phrase. Up to 30 million men in the US have trouble getting or maintaining an erection sufficient for sexual intercourse, according to recent estimates. It can affect men of all races and ages, though rates are moderately higher among men aged 70 and older, compared to men in younger age groups.
Contrary to popular belief, however, aging does not cause erectile dysfunction. A wide range of physical and psychological conditions can lead to erectile dysfunction, including high blood pressure, heart disease, diabetes, anxiety, depression and lifestyle factors such as alcohol and illicit drug use and smoking.
Another common cause of erectile dysfunction is prescription medications, and six types of drugs in particular have the biggest effect on libido.
“No question these impact erectile function,” says Landon Trost, MD, founder of the Male Infertility and Peyronie’s Clinic in Orem, Utah. It is not clear why blood pressure lowering medications can cause ED, but it reverses if a patient quits taking the drug. Beta blockers, thiazide diuretics and loop diuretics are among the ones more likely to cause erectile dysfunction. ”If the medication can be switched for another blood pressure drug, angiotensin receptor blockers or ACE inhibitors are preferred,” adds Trost.
Often prescribed to treat prostate cancer, androgen blockers, also called androgen receptor antagonists, include Casodex (bicalutamide) and flutamide and can cause erectile dysfunction and decreased libido along with many other side effects. “It typically takes several months to years to see the full impact of these medicines, and often they cannot be discontinued,” says Trost, unless they were prescribed for recurrent long-lasting erections — a condition called priapism — in the first place. In that case, your doctor may be able to prescribe an alternative medication.
Hair loss drugs
Hair loss medications include Propecia (finasteride), which is also sold under the brand name Proscar for benign prostatic hyperplasia (BPH), and Avodart (dutasteride), a BPH drug used off label to treat male hair loss. These drugs “diminish dihydrotestosterone levels and suppress libido in about 10% of men but these effects are much more profound in younger guys,” according to Jesse N. Mills, MD, an associate clinical professor of urology at the David Geffen School of Medicine at UCLA Health and director of the Men’s Clinic at UCLA. “Try stopping and using minoxidil instead for hair preservation,” if you have erectile dysfunction that is caused by one of these drugs, he advises.
Sedatives and anxiolytics
“Anything that depresses nerves, such as Xanax (alprazolam), Ativan (lorazepam), Valium (diazepam), alcohol, and any of the sleep aids often impact erectile function,” says Trost. The effect is reversible and is most likely caused by direct suppression of nerve signals or possibly by changes in hormonal signaling. Mills adds that “narcotic use causes suppression of testosterone which can alter blood flow to the penis.”
These commonly prescribed medications affect sexual function in different ways depending on the specific type of drug and how it works. “Central regulation of erections relies on dopamine and serotonin, so any impact on these processes can worsen erectile function,” says Trost. Antidepressants most likely to cause erectile dysfunction include selective serotonin reuptake inhibitors (SSRIs, including Prozac and Paxil), serotonin and norepinephrine reuptake inhibitors (SNRIs, including Effexor XR and Cymbalta), tricyclic and tetracyclic antidepressants, such as Pamelor and Anafranil, and monoamine oxidase inhibitors (MAOIs, such as Marplan). Trost notes that Wellbutrin (bupropion) and Remeron (mirtazapine) are among the antidepressants that have the least impact on erectile function.
Commonly used to treat allergy symptoms, heartburn or motion sickness, certain antihistamines may impact sexual function. Among its many roles in the body, histamine is thought to act as a neurotransmitter and appears to contribute to sexual arousal and erections. One antihistamine, Tagamet (cimetidine), appears to have antiandrogen properties, leading to reduced testosterone levels and thus, sexual dysfunction. Other antihistamines that may contribute to erectile dysfunction include Benadryl (diphenhydramine), Claritin (loratidine), Dramamine (dimenhydrinate), Antivert (meclizine) and Zantac (ranitidine).
While each of these medications alone can affect erectile function, “the greater the number of medications a patient is taking, the greater the impact on sexual function,” says Trost. “In addition to eliminating as many of these as possible, changing to an alternative where possible, and optimizing health through lifestyle choices, we can typically treat the erectile dysfunction directly through other therapies.”
While you shouldn’t stop taking prescribed medications without consulting your healthcare provider, you can have a discussion about whether a particular drug is necessary in the first place, suggests Mills. “For blood pressure medications and antidepressants, there are alternatives that most physicians know to prescribe if a man is having erectile dysfunction,” he says.