Renal/GU pharm overview Flashcards
what is the ending for alpha 1 adrenergic receptor antagonists
-zosin
what is the main MOA of A1 adrenergic antagonists?
blocks alpha receptors located on the prostate smooth muscle
Causes: reversal of smooth muscle contraction
what is the main effect in the body from A1 adrenergic receptors?
Relaxation of smooth muscle of the bladder neck and prostatic urethra
End result of A1 adrenergic antagonists
improve urine output
overall side effects of A1 adrenergic antagonists
- dizziness
- rhinitis
- hypotension
1st generation selective alpha1 antagonists
list 2
- Prazosin
- Alfuzosin
2nd generation selective A1 antagonist
list 4
- tamulosin
- doxazosin
- terazosin
- sildosin
what A1 antagonist is extended release?
Sildosin
Benefit of 2nd gen a1 antagonists?
enabled QD
what 4 A1 antagonists can also impact BP?
- prazosin
- doxazosin
- terazosin
- tamsulosin
tamsulosin trade name
flomax
what A1 antagonis that also lowers BP has the least effect?
Tamsulosin
what is tamsulosin indicated for?
BPH
Kidney stones
What type of patient should tamsulosin be used with caution in?
Pt with orthostatic hypotension
when should tamsulosin never be used?
pts undergoing eye surgery
what are the 3 high yield side effects of tamsulosin
- orthostatic hypotension
- headache (due to blood vessel dilation)
- Ejaculation failure
starting dose of tamsulosin?
0.4 PO QD taken 30min after a meal
food increases onset time
onset of tamsulosin
4-8 hours
what is the MOA of Doxasozin
completely inhibits the postsynaptic A1 adrenergic receptors causing vasodilation and decreased sympathetic tone (in the prostate)
what is the effect of Doxazosin for treatment of HTN
vasodilation of the veins and arterioles that decreases total peripheral resistance
what is the brand name of doxazosin
Cardura
what is the effect within the body of doxazosin for treatment of BPH
decreases sympathetic tone
of the urethra stricture
what is the high yield side effect of Doxaszosin?
Edema (due to venous dilation)
what is the MOA of terazosin
reversible a1 antagonist with MINIMAL effect on A2
what a1 antagonist preserves the negative feedback?
Terazosin
what A1 antagonist leads to decreased arterial tone?
Terazosin
what A1 antagonist causes myasthenia
Terazosin
when should terazosin be taken?
at bed time to avoid syncope
what are the three types of anti-androgens
- 5 a-reductase inhibitors
- Receptor inhibitors
- steroid synthesis inhibitors
what class is finasteride?
5 a-reductase inhibitor
what is the brand name of finasteride?
Proscar
what is the MOA of finasteride
competitively inhibits type 2, 5 alpha reductase which inhibits the conversion of testosterone to dihydrotestosterone
what three things happens within the body when taking finasteride
- suppresion of serum dihydrotestosterone
- reduction of prostate size
- improves urinary flow
what drug should be used with finasteride for symptomatic BPH
finasteride + alpha blocker (doxazosin) to reduce symptom progression
what size prostate indicates use of finasteride?
40g or more
what are the 2 main side effect of finasteride
- decreased libido
- gynecomastia
what drug is also indicated for alopecia (male pattern hair loss)
finasteride
how quickly do dihydrotestosterone levels and prostate size return to normal after stopping finasteride?
dihydrotestosterone: 14 days
prostate size: 3 months