drugs that can cause erectile/sexual dysfunction
- alcohol - SSRIs, SNRIs - BBs, clonidine, thiazide diuretics - 1st gen antipsychotics - prolactone-raising 2nd gen antipsychotics (risperidone, paliperidone) - finasteride, dutasteride, silodosin
natural products used to treat ED
- yohimbe - L-arginine - panax ginseng
1st line treatment for ED
PDE5 inhibitors - sildenafil - vardenafil - tadalafil - avanafil
what are other indications for some PDE5 inhibitors?
- tadalafil: BPH, PAH - sildenafil: PAH
PDE5 inhibitors
- MOA: inhibits cGMP degradation, causing increased smooth muscle relaxation - does not increase libido, drugs won't work if no libido - CI with nitrates and riociguat - dose-related impaired color discrimination - hearing loss, visiono loss - hypotension - priapism - HA, flushing, dizziness - dyspepsia - back pain (mostly tadalafil) - CYP3A4 substrates
sildenafil
(Viagra), PDE5 inhibitor - on-demand: usually start at 50 mg 1 hour before sex - do not take with high fat or large meal, decreased efficacy
vardenafil
PDE5 inhibitor - on-demand: usually start at 10 mg 1 hour before sex
tadalafil
(Cialis, Adcirca), PDE5 inhibitor - daily dosing: 2.5-5 mg daily - on-demand: usually start at 10 mg ≥ 30 minutes before sex - renal dose adjustments for CrCl ≤ 50 and < 30 - avoid with alpha-1 blockers
avanafil
PDE5 inhibitor - take 15-30 minutes before sex
what populations should a PDE5 inhibitor does should start with half the usual dose?
- ≥ 65 y/o - using an alpha-blocker - using a CYP3A4 inhibitor - severe renal or liver disease
when is it okay for patients taking alpha-1 blockers to start PDE5 inhibitors?
after being stable on the alpha-1 blocker without excessive dizziness/hypotension
alprostadil
prostaglandin E1 - MOA: vasodilates the cavarnosal arteries of the penis to enlargen it - CI in priapism - injection or urethral pellet insertion, very painful - does not last as long as PDE5 inhibitors - used by men who can't tolerate or have CIs to PDE5 inhibitors - store in fridge
what is hypoactive sexual desire disorder (HSDD)?
low sexual desire that causes marked distress or interpersonal difficulty that is not due to a health condition or drug
what is the single population that HSDD treatment is indicated for?
premenopausal females
flibanserin
- MOA: unknown but has 5-HT1A agonist activity and 5-HT2A antagonist activity - indicated for premenopausal women only - not very effective - CI with alcohol, REMS required - CI with moderate-strong CYP3A4 inhibitors - hypotension, syncope - avoid in pregnancy/breastfeeding
bremelanotide
- MOA: unknown but is a nonselective melanocortin receptor agonist - SQ injection - CI in HTN or known CV disease - avoid in pregnancy