Update on the Use of Phosphodiesterase Inhibitors in the Treatment of Erectile Dysfunction

Abstract

Oral therapy for erectile dysfunction with type-5 phosphodiesterase (PDE5) inhibitors has revolutionized treatment. This review presents a comprehensive update on PDE5 inhibitors and covers areas including erectile physiology, pharmacology, dosing and side effects. In addition, the use of these drugs in certain clinical situations including cardiovascular disease, as well as a discussion of rare adverse events, daily dosing, use of these drugs for the treatment of lower urinary tract systems, recreational use, novel uses for PDE5 inhibitors, and strategies for treatment failures are covered in detail. Because of the widespread use of PDE5 inhibitors for the treatment of erectile dysfunction, a comprehensive under-standing of these issues by health-care providers is necessary to ensure safe and effective prescribing practices and to improve patient satisfaction and quality of life.

Phosphodiesterase Type 5 (PDE5) Inhibitors in Erectile Dysfunction: The Proper Drug for the Proper Patient

“…Although PDE5 inhibitors were initially approved as on‐demand therapy, in 2008, tadalafil was also approved for everyday use in 2.5‐mg or 5‐mg doses [11,15].…”

“…In diabetic patients, tadalafil once daily was efficacious and well tolerated [7,24], and its effect seemed to persist in a significant percentage of patients after cessation of a 12‐month continuous treatment [25]. Interactions in the administration of PDE5 inhibitors with concomitant oral hypoglycemic drugs or insulin are not described [7,15].…”

“…Conversely, PDE5 inhibitors should be initiated at the lowest recommended dose in patients using alpha‐blockers [7,17]. As no specific trials have been conducted in patients taking any antihypertensive drug starting daily treatment with tadalafil 5 mg, blood pressure should be monitored and an adjustment in the antihypertensive dose may be necessary [13,15].…”

“…A period of >24 hours for short‐acting PDE5 inhibitor (sildenafil, vardenafil), up to 48 hours for long‐acting tadalafil, is recommended before taking nitrates. Due to this possible interaction, short‐acting PDE5 inhibitors should be preferred in patients with concomitant CV disease [7,15,30]. Particular precaution is suggested in the use of labetalol and carvedilol (mixed alpha‐ and beta‐blocker).…”