Pharm Flashcards Preview

Urology > Pharm > Flashcards

Flashcards in Pharm Deck (52)
Loading flashcards...
1

Classes used for BPH?

- alpha 1 blockers (MC)
- 5 alpha reductase inhibitors (MC)
- combo:
Dutasteride-Tamulosin (Jalyn)
- Tadalafil (Cialis)

2

Class of Alpha-1 blockers?

- Terazosin (Hytrin)
- Doxazosin (Cardura)
- Alfuzosin (Uroxatrol)
- Tamsulosin (Flomax)
- Silodosin (Rapaflo)

- combo 5-alpha reductase inhibitor - alpha 1 blocker: Dutasteride-Tamulosin (Jalyn)

3

Use and MOA of Alpha-1 blockers?

- More effective than 5-alpha reductase inhibitors for short and long term sx management***
- MOA: relax smooth muscle in bladder neck and prostatic capsule and prostatic urethra
- Alpha-1 receptors located in base of bladder and in prostate
- all drugs in this class have similar efficacy

4

Efficacy of alpha-1 bockers?

-sx scores decreased by 30-40%
-urine flow rates increased by 16-25%
- Doxazosin (Cardura) and Terazosin (Hytrin) more effective than 5-alpha reductase inhibitor Finasteride (Proscar)
- efficacy of Tamsulosin (Flomax) and Finasteride (Proscar) equal

5

MC SE of alpha-1 blockers? What is done to decrease this?

- MC: dizziness and orthostatic hypotension- Terazosin (Hytrin) and Doxazosin (Cardura) cause more BP lowering than others - can cause severe hypotension if used with phosphodiesterase 5-inhibitors
- Flomax, Uroxatrol, and Rapaflo have less BP effects
- generally start at small dose at bedtime and titrate up slowly over several weeks

6

Other SEs of alpha-1 blockers?

- asthenia (muscle weakness)
- nasal congestion
- problems with ejaculation: mostly Tamsulosin (Flomax), can decrease volume of ejaculate by 90%, 35% may have no ejaculate, and up to 28% have retrograde ejaculation on Silodosin (Rapaflo)

7

Class of 5 alpha-reductase inhibitors?

- Finasteride (proscar)
- Dutasteride (avodart)
- combo:
Dutasteride-Tamulsoin (Jalyn)

8

Use of 5-alpha reductase inhibitors?

- only agents that provide long term decrease in prostate size** and decreased need for prostatic surgery
- but not as effective at controlling sxs as alpha-1 blockers

9

MOA of 5-ARIs?

- competitive inhibitor of both tissue and hepatic 5-alpha reductase
- results in inhibition of conversion of testosterone to dihydrotestosterone and markedly suppresses serum dihydrotestosterone levels - serum dihydrotestosterone decreases by 70% - primary androgen in prostate nad hair follicles
- serum testosterone increases by 10%
- decreases prostatic size

10

Efficacy of 5-ARIs?

- may be up to a yr to notice reduction in sxs
- reduced sx scores:
obstructive: 23%
non-obstructive: 18%
- increase in max urinary flow rate
- reduction in mean prostatic volume by about 18%
- decreased need for surgery
- decreased development of acute urinary retention
- larger prostate volume the more effective med
- Dutasteride (Avodart) may be more potent than Finasteride (Proscar)

11

Major side effects of 5-ARIs?

- decreased libido
- ejaculatory or erectile problems
may only have these effects for 1st yr of therapy
- decreases serum PSA by 50% - use a factor of 2 when interpreting PSA results in first 24 months of therapy
use a factor of 2.5 after 24 months
? decreased development of prostate cancer but concern for possible increased incidence of high grade lesions

12

Use of Cialis for BPH? Don't use with what other meds?

- Blocks PDE5 in prostate and bladder - mechanism of how Cialis reduces BPH sxs isn't completely understood
- Don't use wth nitrates or alpha-1 blockers
- 5 mg daily dose
- takes 2-4 wks to not sx improvement when used for BPH

13

Drugs used for ED?

prostaglandin injectable:
- Alprostadil

phosphodiasterase inhibitors:
- Tadalafil (Cialis)
- Vardenafil (Levitra)
- Sildenafil (Viagra)
- Avanafil (Stendra)

14

Use and MOA of Alprostadil (Caverject, Muse?

- drug category: prostaglandin, vasodilator
- forms: intracavernosal injections, urethral pellets
- MOA:
causes vasodilation by means of direct effect on vascular and smooth muscle, relaxes trabecular smooth muscle by dilation of cavernosal arteries when injected along penile shaft, allowing blood flow to and entrapment in lacunar spaces of penis (corporeal veno-occlusive mechanism)
- onset and duration of action:
onset 5-20 min
duration: less than 1 hr

15

CIs and SEs of Alprostadil (Caverject, Muse)?

- CIs:
conditions that predispose the pt to priapism, anatomic or fibrotic conditions of penis,
for pellets (Muse): urethral stricture, perineal pain

- SEs:
syncope
priapism
may cause BP lowering

16

Class of Phosphodiasterase inhibitors?

- Tadalafil (Cialis)
- Vardenafil (Levitra)
- Sildenafil (Viagra)
- Avanafil (Stendra)

17

MOA of phosphodiasterase inhibitors?

- phsyiologic mechanism of erection of penis involves release of nitrous oxide in corpus cavernosum during sexual stimulation
- NO then activates enzyme guanylate cyclase, which results in increased levels of cyclic guanosine monophosphate (cGMP) producing smooth muscle relaxation and inflow of blood to corpus cavernous
- enhances effect of NO by inhibiting phosphodiesterase type 5 (PDE-5) which is responsible for degradation of cGMP in corpus cavernosum
- don't directly cause penile erections (still need stimulation)

18

CIs of phosphodiasterase inhibitors use?

- men taking nitrates (long acting, can still have SL - wait so many hours)
- caution with alpha-1 blockers due to risk for severe hypotension

19

Adverse rxns of phosphodiasterase inhibitors?

- severe hypotension (w/ nitrates or alpha-1 blockers)
- common: flushing, HAs, dyspepsia
- visual effects: transient blue vision with sildenafil (Viagra), may increase risk for nonarteritic ischemic optic neuropathy
- hearing loss
- priapism
- drug interactions: CYP3A4 inhibitors may increase serum concentration of PDE-5

20

Administration of phosphodiasterase inhibitors?

- in general take 60 min prior to intercourse
- Vardenafil (levitra) and Avanafil (Stendra) have quicker onset of action (30 min)
- food and ETOH delay onset of action of Sildenafil (Viagra) and Vardenafil (Levitra)
- daily dose Tadalafil (Cialis) is available

21

Cost per pills of phosphodiasterase inhibitors?

- Cialis: 10 mg 37.98
- Levitra 10 mg 33.32
- Viagra 50 mg 34
- Stendra 100 mg 29.04

22

How long should you hold nitrates for after use of PDE-5?

- for 24 hours after use or 48 hrs if used Cialis

23

Why is there testosterone replacement?

- to tx low testosterone levels in primary and secondary hypogonadism
- primary: testes fail to produce testosterone
- secondary: pituitary or hypothalamus malfxn

24

MOA of testosterone replacement?

- direct action by binding to androgen receptor
- act in tissues that express enzyme 5-alpha reductase - converts to dihydrotestosterone - binds more readily to androgen receptor than testosterone
- can act as an estrogen after converting to estradiol via an aromatase and bind to estrogen receptor

25

What men should be tx with testosterone? What sxs are being tx? Goal of therapy? When should it not be used?

- only for use in men who are hypogonadal
- sxs that are tx:
decreased libido, decreased AM erections, loss of body hair, low bone density, gynecomastia, small testes, decreased muscle mass
- 3-6 months of therapy needed to note improvement in sxs
- 2 yrs for improvement in BMD
- goal of therapy: return testosterone levels back to normal range

- shouldn't be used to tx impaired spermatogenesis: testosterone therapy suppresses pituitary gonadotropin secretion and leads to more impairment of spermatogenesis

26

Prior to starting testosterone therapy - what needs to be done?

- screen for prostate cancer in men over 50 or in men over age 40 if any risk factors
- screen for erythrocytosis
-if sleep apnea is present - make sure it is being tx

27

SEs of testosterone therapy?

- polycythemia
- worsening of BPH sxs
- acne
- increase in PSA
- oral and prolonged IM doses assoc with multitude of liver issues (jaundice, hepatitis, elevated LFTs)
- increased risk of prostate cancer
- decreased spermatogenesis
- fluid retention
- worsening of sleep apnea
- possible increased risk of CV events (shouldn't start if had event in last 6 months)

28

CIs to testosterone therapy?

- known prostate cancer
- known breast cancer
- severe lower urinary tract sxs
- HCT over 50%
- untx severe sleep apnea
- PSA over 4 mcg/L
- PSA over 3 mcg/L w/ any prostate CA RFs
- CV in last 6 months - relative CI

29

Why is testosterone on FDA watch list - may be assoc with increased risk of what?

- may be assoc with risk of stroke, heart attack, and death in men taking FDA-approved testosterone products
- FDA evaluating 2 diff studies that suggest an increased risk of CV evetns among groups of men Rx testosterone, although agency hasn't concluded that these products increase the risk of stroke, heart attack or death

30

Diff routes of delivery for testosterone?

- oral (hepatic SEs)
- buccal tablet (BID)
- subq pellet (replace 3-6 months)
- nasal gel (TID)
- parenteral (IM): long acting, extra long acting (restricted prescribing)
- transdermal/topical: patch or gel