BPH Flashcards
MOA of alfuzosin
alpha1-a blocker. Relaxes muscles near prostate and bladder neck. Improves lower urinary tract symptoms and has no significant effects of dizziness, asthenia and ejaculatory dysfunction.
ADE of alfuzosin
GI - xerostomia, nausea
CNS - dizziness, somnolence, asthenia, headache, insomnia
Abnormal retrograde ejaculation.
Floppy iris syndrome
Do NOT have to titrate because has less effects on CV system
MOA of tadalafil
relief of BPH via smooth muscle relaxation
ADE of tadalafil
Headache, nausea, URT infections.
Rarely non-arteritic ischemic optic neuropathy hearing loss and retinal artery occlusion.
Contraindicated with organic nitrates = PROFOUND HYPOTENSION made worse with alcohol.
Hepatic 3A4 metaoblized
MOA of saw palmetto
nothing. Studies show it has no benefit on BPH over placebo. Supposedly it inhibits DHT production.
ADE of saw palmetto
doesn’t work
Contrast the pattern of adverse effects for alpha-1a antagonists with that of other alpha-1 drugs.
All have comparable efficacy and common side effects of GI (xerostomia, nausea) and CNS (dizziness, somnolence, asthenia, headache, insomnia). All can cause floppy irish syndrome.
alpha1-a have no need for dose titration and have less effect on CV function!
However alpha1-a can cause retrograde ejaculation and can block dopamine.
Which receptor stimulates detrusor muscle contraction and relaxation of internal urethra sphincter?
M3 receptor (Ach) para makes you pee
Which receptor is predominant in prostatic stroma?
overwhelmingly alpha-1a.
alpha1-d to a lesser extent
Where does the alpha-1d receptor predominate in the urinary system?
bladder and detrusor muscle. D for detrusor
Which receptors allow urine storage?
B3 (NorEpi) - inhibit PNS contraction of detrusor
a1 (NorEpi) - mediate contraction of internal urethral sphincter
Nicotinic M receptors (Ach) - contract external urethral sphincter
Which receptor causes constriction of external urethral sphincter?
Nicotinic M receptors (Ach).
