BPH Flashcards
What is Benign Prostatic Hyperplasia
MC benign neoplasm of american men
What are Obstructive signs and symptoms of BPH
Urinary hesitancy
Dribbling
Bladder fullness post voiding
What are Irritative signs and symptoms of BPH
Urinary frequency
Urgency
Nocturia
(longstanding obstruction at bladder neck)
What are complications of BPH
CKD hematuria incontinence recurrent UTI bladder diverticula bladder stones
In which lobe is cancer most common
posterior lobe of prostate
What are the 3 types of tissue of the prostate and what do they do
- Epithelial (glandular)- makes secretions; stimulated by androgens (DHT) to grow
- Stromal (smooth muscle)- has alpha 1 receptors; NE causes contraction (= extrinsic urethra compression= decreased bladder emptying)
- Capsule (fibrous CT and smooth muscle)- has alpha1 receptors; NE causes contraction
What are Testosterone and Androstenedione and what are they responsible for
-Inactive forms converted to DHT (active) by 5a reductase in target cells
penile/scrotal enlargement
increased muscle mass
normal male libido
What is DHT
Active metabolite that has greater affinity for, and forms a more stable complex with intraprostatic androgen receptors
-In prostate, DHT causes growth of gland
What are the two types of 5a reductase (converts testosterone to DHT)
Type 1: local to sebaceous glands in frontal scalp, liver, skin= acne, increased body and facial hair
Type 2: local to prostate, genital, and hair follicles of scalp= more DHT= growth of prostate gland
How do we improve urine flow in men with BPH
Reverse the smooth muscle contraction in enlarged prostate (caused by NE in stromal and capsule)
What are the normal and abnormal prostate gland tissue ratios
Normal= Stromal:Epithelial is 2:1 Abn= Stromal:Epithelial is 5:1
What are the two general Tx for BPH
5a reductase inhibitors= less DHT= reduce enlarged prostate (by 25%)
Alpha antagonist= Sx management of urinary flow (relax smooth muscle so more urine can pass)
What are Static factors of BPH
Enlargement of prostate= physical block at bladder neck= urine obstruction
- Due to 5a reductase converting to DHT in epithelial tissue
- Sx are exacerbated by stress or pain
What are Dynamic factors of BPH
Contraction of prostate around urethra
- Due to excess alpha 1 tone of stromal tissue
- *Sx of dynamic factors are obstructive voiding (with normal size prostate)
How does micturition occur
PNS causes detrusor contraction and internal urethral sphincter relaxation
What meds can exacerbate BH symptoms
Anticholinergics Antihistamines TCA Phenothiazines (dc med usually relieves Sx)
How do you Tx mild ASx or mildle bothersome BPH (if without complications)
Watchful waiting
Behavior modification
Follow up q12 mo to assess worsening S/Sx
What are the 3 categories of BPH drug therapy (mod-severe Sx)
- Reduce static factor: interfere w/ testosterone stimulating prostate enlargement
- Reduce dynamic factor: relax smooth muscle
- Improve urine storage capacity: relax detrusor
Why is BPH MC in 60+ y/o
2/2 androgen driven growth in size of prostate
What reduces dynamic (contraction of stromal tissue) factors of BPH
- nonselective alpha 1 blocker: Prazosin, Alfuzosin (er), Terazosin (ir), Doxazosin* (ir)
- selective alpha 1 blocker: Tamsulosin* aka flomax, Silodosin
- Smooth muscle relaxation: Tadalafil aka cialis (PDE11 inhibitor)
What is significant about Terazosin and Doxazosin
They are second gen, and immediate release
Must slow titrate up to minimize orthostatic hypotension and first-dose syncope
What is the Slow titration (schedule 1) for Terazosin and Doxazosin administration
Day 1-3: 1mg at bedtime
Day 4-14: 2mg
Week 2-6: 5mg
Week 7+: 10mg (bedtime)
What is Quick titration (schedule 2) for Terazosin and Doxazosin
Day 1-3: 1mg at bedtime
Day 4-14: 2mg
Week 2-3: 5mg
Week 4+: 10mg at bedtime
What meds reduce static (enlargement 2/2 5a reductase) factor
- 5a reductase blocker: Finasteride*, Dutasteride
- DHT receptor blocker: Bicalutamide, Flutamide
- Pituitary blocker (no LH): Leuprolide, Goserelin
- Pituitary blocker and androgen receptor blocker: Megestrol acetate
What meds relax the detrusor muscle of bladder
Oxybutynin* (ditropan)
Tadalafil (Cialis)- PDE11 inhibitor
Mirabegron- B3 agonist
What relieves voiding Sx
alpha 1 antagonist (voiding sx are dynamic)
What should patients with a prostate of at least 40g (norm 20) take
5 alpha reductase blocker (no DHT= less enlargement)
What are the ADE of Second generation (IR) alpha 1 antagonists
cardiovascular effects;
first dose syncope, orthostatic hypotension, dizziness
*Use third gen (Tamulosin, Silodosin) as alternatives, they are uroselective
What is Alfuzosin
an extended release second gen that functions as uroselective
Less cardiac effects than Terazosin and Doxazosin
How long do 5a reductase inhibitors take to work
Up to 6 months! Takes a while to shrink the prostate
What are the ADE of 5a reductase inhibitors
Decreased libido ED Ejaculaiton disorders *Gynecomastia (No 5a reductase= no DHT)
What are the ADE of Alpha 1 Antagonists
**Floppy iris syndrome Syncope light headed orthostatic hypotension tachy (cardiac adverse effects) nasal congestion Ejaculatory dysfunction priapism
What must you monitor if taking alpha 1 blockers
BP
HR
How do you administer alpha 1 blockers
start on lowest possible dose
take first dose at bedtime
slowly titrate up
Important info to tell patient (pt education)
If you have had cataract surgery, inform ophthalmologist ASAP to prevent complications
If you have a painful erection lasting longer than 4 hours, seek immediate medical attention
What must you monitor if taking 5a reductase inhibitors
PSA
-If adherent, patients PSA should decrease by 50%
What is the difference in onset time between 5a reductase inhibitors and alpha 1 blockers
a1 blocker: 1-6 weeks peak onset
5a: 3-6 months peak onset
What are ADE of PDE inhibitors
HA, dizziness, congestion, dyspepsia, back pain, myalgia, hearing loss
***If hearing loss occurs, DC Tadalafil
What must you monitor when taking PDE inhibitors
BP
Pulse
hearing loss
What must you monitor if on anticholinergics
mental status
bowel habits
ability to urinate
-ADE are dose dependent and reversible
How does Mirabegron work
B3 receptors are in the bladder- when stimulated, increase cAMP and relax detrusor muscle relieving irritative Sx and increasing capacity
B3 agonist= relaxes detrusor muscle in bladder
Usually onset in 2 weeks, sometime 8
Does have some cardiovascular effects
What are ADE of Mirabegron
*HTN tachy constipation diarrhea HA *Impaired cognition -ADE are dose dependent and reversible
What must you monitor if taking Mirabegron
BP
bowel habits
What are your surgical options for BPH if with mod-severe Sx and patient does not respond/tolerate drug therapy
TURP (do biopsy) Green light (cant do biopsy)
