BPH & ED Flashcards
How is dihydrotestosterone (DHT) formed and what does it do?
Testosterone converted to DHT by 5 alpha reductase in prostate
DHT: normal growth / enlargement of prostate
What is the prostate made up of?
- epithelial tissue (growth stimulated by androgens)
- stromal tissues innervated by alpha1 adrenergic receptors
Pathophysiology of BPH (short term)?
Static component
- testosterone converted to DHT -> prostate enlarges
Dynamic component
- increase smooth muscle tissue & agonism of alpha1 receptors -> narrowing of urethra outlet
=> urethral obstruction, s&sx
Pathophysiology of BPH (long term)?
- early phase: bladder muscle force urine thru narrowed urethra by contracting more forcefully
- over time, bladder (detrusor) muscle becomes thicker (hypertrophy)
- detrusor muscle becomes irritable +/ overly sensitive (detrusor overactivity / instability) -> contract abnormally in response to small amt of urine in bladder
What is LUTS and what does it consist of?
Lower urinary tract sx
- obstructive sx (early stage): hesitancy, weak stream, sensation of incomplete emptying, dribbling, straining, intermittent flow
- irritative sx (late stage If untreated): dysuria, frequency, nocturia, urgency, UI
Complications of BPH?
- recurent UTI
- bladder stones
- acute urinary retention
- UI
- hematuria
What score is used for BPH and what is the score & sx for:
- mild
- moderate
- severe
AUA-SI score
- mild ≤7: asymptomatic / mildly sx
- moderate 8-19: the above + obstructive & irritative voiding sx
- severe ≥20: the above + ≥1 complications of BPH
What is the prostate specific antigen (PSA) for BPH?
> 1.5ng/mL
What postvoid residual is considered inadequate emptying? What is normal?
> 200 mL
(normal <100mL)
What medications contribute to BPH? Why?
- anticholinergics (decrease bladder contractility)
- alpha1 adrenergic agonist (contract prostate smooth muscle)
- opioid (increase urinary retention)
- diuretics (increase urinary frequency)
- testosterone (stimulate prostate growth)
When should treatment be started for BPH? When can watchful waiting be considered?
Start: if sx bother pt / complications
Watchful waiting: mild, or moderate-severe with no bothering sx
Nonpharm for BPH? (5)
- limit fluid intake in the evening
- minimise caffeine & alcohol intake
- take time to empty bladder completely & often
- avoid meds that worsen sx
- transurethral resection of prostate (for complications)
What pharm options are used for BPH obstructive sx?
- alpha1 adrenergic antagonist
- 5 alpha reductase inhibitors
- PDE5 inhibitors (only tadalafil)
What are selective and nonselective alpha1 antagonists?
- selective: alfuzosin, tamsulosin, silodosin
- nonselective: terazosin, prazosin, doxazosin
Are selective or nonselective alpha1 antagonists preferred for BPH? When should the non-preferred one be used?
preferred: selective
nonselective preferred if pt has BPH + HTN (but cannot use as monotherapy)