ic16, ic19 BPH, ED Flashcards
(46 cards)
What is the prostate composed of?
Epithelial (glandular) tissue
Stimulated by DHT
Smooth muscle tissue
Contains a-1 adrenergic receptors
How does BPH occur?
1) Static component (involving epithelial tissue)
Testosterone → DHT by 5a reductase
Prostate tissue enlarges
2) Dynamic component (involving smooth muscle)
A1 receptors activated
Smooth muscle constrict, causes narrowing of urethra
1 + 2 = Urethral obstruction, Symptoms
How does bladder become over-sensitive long term?
Initially, bladder can force urine through narrowed urethra
Over time, bladder hypertrophy and decompensates
Bladder becomes overly sensitive, contract abnormally to small amounts of urine
What are some Obstructive symptoms? (6 points)
When does this occur?
Hesitancy
Weak stream
Sensation of incomplete emptying
Dribbling
Straining
Intermittent flow
Early in disease
What are some Irritative symptoms? (5 points)
When does this occur?
Dysuria (burning sensation)
Frequency
Nocturia
Urgency
Urinary Incontinence (cannot control urination)
Occurs after years of untreated BPH
What is a normal Postvoid Residual?
What is the cut-off for Anti-muscarinic use?
< 100ml
Must be < 250ml
What does Prostate Specific Antigen (PSA) help to predict?
Predict progression of BPH
but not specific, could be high due to cancer
Medications and how they contribute to BPH symptoms (5 points)
Anticholinergics (eg. antihistamines)
→ Decrease bladder contractility
Opioid analgesics
→ Increase urinary retention
Diuretics
→ Increase urinary frequency
Testosterone (DHT)
A1 adrenergic agonist
→ Contract SM
Non-pharm methods for BPH (4 points)
Limit fluid intake at night
Minimise caffeine and alcohol intake
Schedule voiding, empty completely and often
Avoid medications that can exacerbate symptoms eg. diuretics
When to treat BPH? (3 points)
When patient is bothered (QOL > 3)
→ Pharmacotherapy
When Uroflow < 10ml/s + PVR > 100ml
→Do surgery
When:
Urinary retention
Haematuria
Recurrent UTI
Bladder stones (calculi)
→Do TURP (surgery)
When do we do watchful waiting?
When patient has mild symptoms OR patient is not bothered by symptoms despite having moderate or severe symptoms
Examples of Alpha 1 Antagonists?
Where do they act on?
TeD ATaS
Non Selective (Peripheral vessels + Urinary a1 adrenergic receptors)
Terazosin
Doxazosin
Selective a1 antagonist
Alfuzosin
Tamsulosin
Silodosin
Act on the smooth muscle, cause SM relaxation and vasodilation
Difference between Non-selective A1 antagonists VS Selective
Non selective:
block peripheral vascular and urinary a1 adrenergic receptors → Cause hypotension
Selective:
Only blocks urinary receptors
Effect of Alpha 1 Antagonists
Effective in reducing obstructive symptoms with small prostate (< 40g)
Fast onset
Does not reduce prostate size or PSA
BPH can still progress and Surgery is still needed
Most common side effects for Non-selective and Selective A1 antagonists
Non-selective:
Dizziness (take medication at bedtime)
Selective:
Ejaculatory disturbances (Silodosin highest, Alfuzosin lowest)
What must we always check before dispensing A1 antagonists?
If patient is going to do cataract surgery
Tamsulosin may cause Intraoperative Floppy Iris Syndrome (IFIS)
If yes, either hold 14 days before surgery or initiate after surgery completed
Absolute contraindication with Non-selective A1 Antaognist
History of syncope
What is the MOA of 5a reductase inhibitor?
2 examples of 5ARI
Where does 5ARI act on?
Inhibit 5a reductase inhibitor (Type 2), which inhibits Testosterone → DHT
Finasteride, Dutasteride
Acts on glandular tissue, to reduce size of prostate
Who are 5ARI indicated for?
Patients with moderate or severe LUTS + Large prostate (> 40g)
if PSA > 1.5ng/mL
Effect of 5ARI (2 points)
Reduces size of prostate
Decreases PSA levels
Counselling points of 5ARI (2 points)
1) Slow onset, takes 6-12 months to decrease prostate size
2) Teratogenic
Pregnant or Females of child bearing age should NOT handle these agents
Side effects of 5ARI (3 points)
Ejaculatory disorders
Decreased libido
Erectile dysfunction
What should we do before initiating 5ARI?
Obtain baseline PSA, as PSA levels will decrease after starting 5ARI
What does PDE5i stand for?
Which PDE5i is approved for BPH?
Dose?
Side effect of PDE5i
Phosphodiesterase 5 Inhibitor
Tadalafil 5mg OD
Significant hypotension
