BPH Flashcards
Obstructive s/s of BPH?
urinary hesitancy
urine dribbling
bladder fullness post voiding
Irritative s/s of BPH?
result from long-standing obstruction at the bladder neck
urinary frequency
urgency
nocturia
Complications of BPH progression?
chronic kidney disease
gross hematuria
urinary incontinence
recurrent UTI
bladder diverticula
bladder stones
Normal prostate size?
2 x 3 x 4 cm
weighs ~ 20g
What are the 3 types of tissue in the prostate?
epithelial tissue (aka glandular)
stromal (aka smooth muscle)
capsule
What stimulates epithelial tissue growth?
androgens
Stromal tissue and the capsule is embedded with….
alpha 1 adrenergic receptors
-norepinephrine causes smooth muscle contraction and capsule contraction around the urethra
What is the principal testicular androgen?
What is the principal adrenal androgen?
testosterone
Androstenedione
Testosterone and Androstenedione are responsible for….
penile and scrotal enlargement
increased muscle mass
maintenance of the normal male libido
Testosterone and Androstenedione are converted by…. in target cells to….
5 alpha reductase
dihydrotestosterone (DHT), an active metabolite
Which is a more potent androgen in the prostate, DHT or testosterone?
DHT
What does DHT do in the prostate?
induces growth and enlargement of the gland
What drug class can help to reduce enlarged prostate gland (epithelial tissue)?
5 alpha reductase inhibitors
What drug class can help with sxs due to problem with stromal tissue?
alpha1-adrenergic antagonists are quickly effective in symptomatic management of urinary flow
BPH sxs may be exacerbated by which drug classes?
anticholinergic agents
antihistamines
tricyclic antidepressants
phenothiazines
Goals of BPH management?
control sxs
prevent progression of complications
delay need for surgical intervention
Tx for moderate/severe sxs BPH?
drug therapy or surgery
Sxs of BPH usually result from both…
static and dynamic factors
Which drugs can help to reduce dynamic factors?
Blocks alpha adrenergic receptors in prostatic stromal tissue: Prazosin, Doxazosin, Terazosin
Blocks alpha receptors in the prostate: tamsulosin
Causes smooth muscle relaxation: Tadalafil
What are the 2 types of 5alpha reductase?
Type I- localized to sebaceous glands in frontal scalp, liver and skin > causes acne and increased body and facial hair
Type II- localized to the prostate, genital tissue, and hair follicles of the scalp > induces growth and enlargement of the gland
What ratio is exaggerated in BPH?
stromal-to-epithelial tissue ratio of 5:1
normal is 2:1
What drug class can help with sxs due to problem with stromal tissue?
alpha1-adrenergic antagonists are quickly effective in symptomatic management of urinary flow
What are static factors involved in BPH?
anatomic enlargement of the prostate gland
> depends on androgen stimulation of epithelial tissue and estrogen stimulation of stromal tissue in the prostate
What are dynamic factors involved in BPH?
excessive alpha-adrenergic tone of the stromal component of the prostate gland
> results in contraction of the prostate gland around the urethra and narrowing of the urethral lumen
What are the 3 categories of drug therapies for BPH?
- Agents that interfere with testosterone’s stimulatory effect on prostate gland enlargement (static)
- agents that relax prostatic smooth muscle (dynamic)
- agents that relax bladder detrusor muscle (improves urine storage capacity)
Which drugs can help to reduce dynamic factors?
Doxazosin, Terazosin, Prazosin, etc.
Tamsulosin
Tadalafil
What are the two ways to dose IR Terazosin and Doxazosin?
Schedule 1: slow titration
Schedule 2: quicker titration
(slow to minimize orthostatic hypotension)
What mechanisms reduce static factor?
blocks 5 alpha reductase enzyme (Finasteride)
Blocks diihydrosterone at its IC receptor
blocks pituitary release of LH
blocks pituitary release of LH and blocks androgen receptor
MOA of Oxybutynin and Mirabegron?
relaxes detrusor muscle of bladder
Role of alpha 1 adrenergic antagonist?
relieves voiding sxs
Older second-generation immediate-release formulations(e.g., terazosin, doxazosin) can cause…
adverse CV effects: 1st dose syncope, orthostatic hypotension, dizziness
Name 2 3rd generations alpha 1 adrenergic antagonists
Tamulosin, Silodosin
Uroselective agents, good alternatives
Which patients are 5 alpha reductase inhibitors good for?
for pts with large prostates who wish to avoid surg and can’t tolerate the side effects of alpha1 adrenergic antagonists
Disadvantage of 5 alpha reductase inhibitors?
SLOW ONSET, taking up to 6 months for maximal effects
What should you monitor in pts taking alpha adrenergic antagonists?
BP, HR
ADEs of alpha adrenergic antagonists?
floppy iris syndrome, priapism, syncope, lightheadedness, orthostatic hypotension, nasal congestion
What should you monitor in a pt taking 5 alpha reductase inhibitors?
PSA
should decrease by 50% iif adherent to therapy(
ADEs of 5 alpha reductase inhibitors?
Erectile dysfunction
Decreased libido
Ejaculatory dysfunction
Gynecomastia
What should you use if you need to fix BPH immediately?
What if sxs are just mild and prostate is enlarging slowly?
alpha1 adrenergic antagonists
5 alpha reductase inhibitors
ADEs of phosphodiesterase inhibitors?
Headache Dizziness Nasal congestion Dyspepsia Back pain Myalgia Hearing loss
What side effect would make you want to discontinue Tadalafil?
hearing loss
Name a beta3 adrenergic agonists. What does it do?
Mirabegron
release cAMP, which relazes the detrusor muscle –> reducing the irritative voiding sxs (increased urinary bladder capacity)
ADE of Mirabegron?
HTN
impaired cognition
others: tachycardia, dry mouth, nausea, constipation, HA
Surgical option for BPH?
for pts with severe sxs who don’t respond to or don’t tolerate meds
TURP (Bx possible)
Green Light (no bx possible)
Tx for mild sxs?
watchful waiting
Tx for moderate sxs with ED?
alpha-adrenergic antagonist
phosphodiesterase inhibitor
or BOTH
Tx for moderate sxs with small prostate and low PSA?
alpha-adrenergic antagonist
Tx for moderate sxs with large prostate and increased PSA?
5 alpha reductase inhibitor
+
alpha-adrenergic antagonist
Tx for moderate sxs predominant irritative voiding sxs?
alpha-adrenergic antagonist
+ anticholinergic agent
OR
alpha-adrenergic antagonist +
Mirabegron
Tx for severe sxs with complications?
minimally invasive surg or prostectomy?
Which decreased prostate size; alpha1 adrenergic antagonists or 5alpha reductase inhibitors?
5 alpha reductase inhibitors
Which relaxes prostatic smooth muscle; alpha1 adrenergic antagonists or 5alpha reductase inhibitors?
alpha 1 adrenergic antagonists
which halts disease progression; alpha1 adrenergic antagonists or 5alpha reductase inhibitors?
5 alpha reductase inhibitors
which has CV adverse effects; alpha1 adrenergic antagonists or 5alpha reductase inhibitors?
alpha 1 adrenergic antagonists
