Drugs for Erectile Dysfunction Flashcards
Drugs for Erectile Dysfunction
Alprostadil Methyltestosterone Avanafil Testosterone Sildenafil Tadalafil Yohimbine Vardenafil Alfuzosin †
Alprostadil Mechanism:
PGE1 agonist: Increases cAMP which increases PKA this leads to decrease intracellular Ca2 & smooth muscle relaxation.
Local Delivery of Alprostadil:
Urethral suppository Dissolves in residual urine
Intra-cavernosal injection
Alprostadil Duration:
Rapid onset (minutes); durable effect (½-several hrs) Varies by patient.
Alprostadil Adverse Effects:
Rarely (≤ 3%) adverse CV effects reported. Prudent to monitor and initially dose-titrate in patients with preexisting CV disorders.
Oral Drugs?
Avanafil
Sildenafil
Tadalafil
Vardenafil
Avanafil Metabolism Tmax, hr T½, hr Common adverse effects Rare but serious adverse effects
3A4>>2C; fecal/renal (3:1) ½-¾ 5 headache <10% Non-arteritic ischemic optic neuropathy, sudden hearing loss; unstable angina
Sildenafil Metabolism Tmax, hr T½, hr Common adverse effects Rare but serious adverse effects
3A4»2C; fecal/renal (4:1)
delayed by high fat meal to > 1
4
headache <46%; indigestion ~17%; visual disturbances ~11%; epistaxis 9%
Non-arteritic ischemic optic neuropathy, Anterior, sudden hearing loss
Tadalafil Metabolism Tmax, hr T½, hr Common adverse effects Rare but serious adverse effects
3A4; fecal/renal (2:1)
2-4 hr
<42%; indigestion ~13%; naasea 13%;
backache 12%; myalgia 14%; flushing 13%; resp tract infect. 13% nasopharyngitis 13%
Non-arteritic ischemic optic neuropathy,
Anterior, sudden hearing loss; CV adverse effects;
angina, MI, tachycardia
Vardenafil Metabolism Tmax, hr T½, hr Common adverse effects Rare but serious adverse effects
3A4 & 2C; fecal/renal (9:1)
1 hr; bioavailability decrease by high fat meal
~5
headache 15%; flushing 11%; rhinitis 9%
Non-arteritic ischemic optic neuropathy, sudden hearing loss; angina, MI
Drug Interactions for the "afils" & mechanism? Avanafil Sildenafil Tadalafil Vardenafil
• Absolute contraindication: NITRATES • Potential interactions with: – Alpha-blockers increase hypotension – Drugs affecting CYP activity PDE5 inhibitors
Vardenafil: interaction with
> 70 drugs leading to increase risk of QT prolongation
Approximately 65% of hypogonadal men may have
improvement in?
Erectile function with testosterone replacement therapy.
Testosterone replacement therapy may improve?
The response of hypogonadal men to PDE5 inhibitors such as sildenafil citrate
Yohimbine Response rate?
Response ranges from 34-86% in placebo-controlled, double-blind trials in patients with ED
– High placebo effect
– Drug > placebo in only minority of trials
