Sexual Side Effects of Alpha Blockers and 5-Alpha-Reductase Inhibitors

ORLANDO, Fla., May 18, 2014 /PRNewswire-USNewswire/ -- Two studies evaluating the sexual function in men with Lower Urinary Tract Symptoms (LUTS) as well as post bilateral nerve-sparing radical prostatectomy will be presented to the media at a special press conference during the 2014 Annual Scientific Meeting of the American Urological Association (AUA). Tobias S. Köhler, MD, MPH, FACS; associate professor & residency program director with Southern Illinois University School of Medicine will moderate the session, which will take place on Sunday, May 18, 2014 at 2:00 p.m. ET, in the Orange County Convention Center, Orlando, FL.

Study Details
Tadalafil Once a Day Significantly Reduces Penile Length-Loss in Patients Post Bilateral Nerve-Sparing Radical Prostatectomy – Results from a Randomized Controlled Trial (#MP48-10): Erectile dysfunction following radical prostatectomy for clinically localized prostate cancer is a known side effect to the surgery; however with the introduction of the nerve-sparing radical prostatectomy technique, many men can expect to recover erectile function, but early recovery of natural erectile function is not common. Increasing attention has been given to this concern in recent years and is why researchers from Canada, the United States and five European countries compared the efficacy and protective effect of Tadalafil (a phosphodiesterase type 5 inhibitor approved to treat erectile dysfunction), on penile function after nerve-sparing radical prostatectomy.

Researchers conducted a randomized, nine month double-blind, double-dummy, placebo-controlled clinical trial in men ≤68 years of age with normal pre-operative erectile function. More than 420 patients were randomly allocated to receive one 5 mg Tadalafil on a daily basis, one 20 mg Tadalafil on demand or a placebo, followed by a six week drug-free washout and a three month open-label once a day treatment.  Secondary outcome measures included change of stretched penile length, responses to Sexual Encounter Profile Questions one and three and the Standardized Morning Erection Question.

Results showed:

• Of the four hundred twenty-three patients randomized to Tadalafil once daily (n = 139 Tadalafil), on demand (n = 143), and placebo (n = 141), greater erectile function was retained with Tadalafil at the end of the nine month double-blind treatment.
• ­Men who took Tadalafil 5 mg once daily experienced improved erectile function than those who were given Tadalafil 20 mg on demand or nothing at all. 
• Penile tumescence (SEP 1) and the ability for sexual intercourse (SEP 3) significantly improved for patients on Tadalafil once a day versus those on placebo.
• At month nine, penile length loss was significantly reduced versus placebo in the Tadalafil once daily group only (LS mean difference 4.1 mm; 95 percent CI, 0.4–7.8; p = 0.032).

Researchers concluded Tadalafil may have a role in the recovery of erectile function after prostatectomy and possibly provide protection from penile structural changes.

Change in Sexual Function in Men with LUTS/BPH Associated with Long-Term Treatment with Doxazosin, Finasteride and Combined Therapy (#PD23-06): The incidence of benign prostatic hyperplasia (BPH) and resulting lower urinary tract symptoms (LUTS) in men increases with age. For those with BPH/LUTS, many not only have trouble urinating, but also experience changes in their sexual function. Doxazosin and Finasteride are two drugs used either alone, or in combination, to treat the symptoms of BPH/LUTS.

Comprehensive assessments of sexual function in men with LUTS who are treated long-term with drugs such as Doxazosin, Finasteride or a combination of the two is lacking, which is why leading researchers from Illinois and Maryland recently completed a study examining the effects both drugs had on a man's sexual function. Utilizing data from the multi-center, randomized, double-blind, placebo-controlled clinical trial, Medical Therapy of Prostatic Symptoms, more than 2,780 men were analyzed with changes in sexual function assessed by the Brief Male Sexual Function Inventory (BMSFI).

Results showed:

• Men taking Finasteride experienced significant worsening of ejaculatory function than those not.
• Men prescribed both Doxazosin and Finasteride also experienced significant worsening in erectile function and sexual problem assessment
• There was no significant difference in changes in any of the BMSFI domains when men assigned to Doxazosin were compared to those on placebo.

Researchers concluded treatment with Doxazosin alone had minimal, if any, negative impact on sexual function in men with LUTS, while treatment with Finasteride was associated with a worsening of several domain of sexual function.

"The use of oral medications in treating certain urologic conditions can be associated with both beneficial outcomes as well as potentially unfavorable long-term effects on a man's sexual health," said Dr. Köhler.  "When discussing treatment options with patients, physicians should make certain they cover any potential positive or negative effects the treatments may have on a man's sexual function and overall health, which will help to better inform their decision-making on treatment."

About the American Urological Association: The 109^th Annual Meeting of the American Urological Association takes place May 16 – 21 at the Orange County Convention Center in Orlando, FL.

Founded in 1902 and headquartered near Baltimore, Maryland, the American Urological Association is a leading advocate for the specialty of urology, and has more than 20,000 members throughout the world. The AUA is a premier urologic association, providing invaluable support to the urologic community as it pursues its mission of fostering the highest standards of urologic care through education, research and the formulation of health policy.

Contact:
Christine Frey, AUA
410-999-7091, [email protected]

SOURCE American Urological Association