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242 Cards in this Set
- Front
- Back
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What can be an underlying cause of ED?
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disease that compromise vascular flow to corpora cavernosum (peripheral vascular disease, arteriosclerosis, essential HTN)
diseases that impair nerve conduction to the brain (spinal cord injury or stroke) conditions that impair peripheral nerve conduction to the penile vasculature (DM), smoking, chronic ethanol abuse |
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What should an ideal tx of ED have?
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fast onset, be effective, convenient to administer, cost effective, low incidence of serious AE, free of serious DI
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Why are vacuum erection devices better to use for a couple in a stable relationship?
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slow onset of action (30 minutes) and are not discreet
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Do PDE inhibitors work for all causes of ED?
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yes
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How often to PDE inhibitors fail?
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30-40%
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When are PDE inhibitors CI?
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pts taking any dosage formulation of nitrate
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When should testosterone supplementation be used?
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pts with primary or secondary hypogonadism with ED from decreased libido
should not be used if serum testosterone levels are normal |
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How often do intracavernosal injections or intraurethral pellets of alprostadil fail?
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1/3 of pts
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What medications are associated with a high incidence of ED?
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BB
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What systems are involved in an erection?
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vascular, nervous, and hormonal
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What effect does acetycholine have on blood flow into corpora?
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enhanced by Ach mediated vasodilation
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Does Ach directly enhance arterial flow to corpora?
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no, it is a coneurotransmitter that works with cGMP, cAMP, or vasoactive intestinal polypeptide to produce vasodilation
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What causes erection while sleeping?
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sacral nerve reflex arc
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What part of the brain is responsible for integrating external stimuli?
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medial preoptic area of the hypothalamus
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What produces proerctogenic effect in medial preoptic area of hypothalamus?
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dopamine
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What causes penis to remain flaccid?
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alpha 2 adrenergic stimulation
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After moving down the spinal cord, how do nerve impulses travel to the penis?
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efferent peripheral nerves
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What are the inhibitory sympathetic neurons?
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T11-L2
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What are the proerectogenic parasympathetic neurons?
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S2-S4
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What are the proerectogenic somatic neurons?
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S2-S4
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What is the progression of an erect penis to a flaccid state?
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detumescence
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What causes detumescence?
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NE, contracts vascular smooth muscle to decrease arterial inflow to corpora and contracts sinusoidal tissue in the corpora, venous outflow from corpora increases
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What is normal range of testosterone?
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300-100ng/dL
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How common is hypogonadism?
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1/3 of me over 50
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What is hypogonadism?
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subphysiologic serum testosterone levels
pts complain of loss of energy, loss of muscle strength, depressive mood, and decreased libido |
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What is organic ED?
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vascular, neurologic, or hormonal etiologies of ED
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What is ED that doesn't respond to psychogenic stimuli?
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psychogenic ED
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Is there more organic or psychogenic ED?
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80% organic
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Is organic or psychogenic ED more severe?
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organic
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What can lead to psychogenic ED?
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malaise, reactive depression or performance anxiety, sedated, Alzheimer's, hypothyroidism, mental disorder
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What effect does cigarette smoking have that may lead to ED?
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vasoconstrictor
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What effect does ethanol have that may lead to ED?
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androgen deficiency, peripheral neuropathy, chronic liver disease
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What % of ED is caused by meds?
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10-25%
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What are physical signs of hypogonadism?
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gynecomastia, small testicles, decreased body hair, decreased muscle mass
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table 86-2
pt 1372 |
table 86-2
pg 1372 |
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What are signs of hypogonadism?
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gynecomastia, small testicles, and decreased body hair
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What is Peyronie's disease?
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disease associated with abnormal penile curvature
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How can you check the vascular supply to the genitals?
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femoral and lower extremity pulse
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How do you check the nerve supply to the penis?
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anal sphincter tone and other genital reflexes
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What age should digital rectal exam begin?
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50 years old
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What is the purpose of a digital rectal exam?
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rule out benign prostatic hyperplasia
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What labs should be run for ED diagnosis?
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fasting serum blood glucose and lipid profile
serum testosterone in older than 50 years or if have decreased libido |
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When should serum testosterone levels be tested, and how many do you need?
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in the morning, 2 serum testosterone levels to confirm hypogonadism
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How should arteriosclerosis be ruled out as cause of ED?
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cardiovascular risk assessment
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What is the first step in managing ED?
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identify and reverse underlying causes
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Can psychotherapy be used as monotherapy?
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yes for psychogenic ED, can also be used as an adjunct to specific tx
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Who should be in psychotherapy?
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pt and partner, to enhance the relevance
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Is psychotherapy short term?
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no, long-term is often needed and the effectiveness is generally low
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table 86-3 pg 1373
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table 86-3 pg 1373
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What is line of tx for organic ED?
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oral PDE inhibitor or vacuum first, intracavernosal therapy, intraurethral alprostadil, prosthesis
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What is the onset of vacuum erection device?
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30 minutes
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WWho do vacuum erection devices work best in?
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older pts who are married or have a stable sexual relationship because they are not discreet (first line in these pts)
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What is complaint of vacuum erection device?
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penis cool to the touch or discolored
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What usually cause pain or injury when using vacuum erection device?
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constriction bands
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When are vacuum erection devices CI, and when should they be used cautiously?
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CI in sickle cell disease because prone to priapism which can be exacerbated
use cautiously in pts taking PO anticoagulants because warfarin may cause priapism |
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How do phosphodiesterase inhibitors work?
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inhibit the catabolism of cGMP
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What is the pathway for getting an errection?
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sexual stimulation - NO released by neurons of endothelial cells in penile tissue - NO stimulates guanylate cyclase which increases tissue cocncentration of cGMP. Increased levels of cGMP produce penile erection - cGMP is catabolized by PDE and converted to GMP which is inactive
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What PDE isoenzyme is inhibited by current PDE inhibitors?
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type 5
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Where else are PDE isoenzyme type 5 also found?
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peripheral vascular tissue, tracheal smooth muscle, platelets, may produce unwanted effects
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Which of the PDE inhibitors is the most effective?
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they are equally effective
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What pts have the lowest response rates to PDE inhibitors?
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DM or pts after radical prostatectomy
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How many pts are nonresponders to PDE inhibitors?
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30-40%
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Is foreplay required when taking a PDE inhibitor?
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yes
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Should PDE inhibitors be taken on an empty stomach?
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sildenafil should, other 2 can be taken without regard to meals
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What effect does a fatty meal have on the absorption of PDE inhibitors?
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sildenafil and vardenafil have decreased absorption, tadalafil is not effected
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How many doses of PDE inhibitors before it is considered a failure?
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5-8
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What is max doses for PDE inhibitors?
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100mg sildenafil, 20mg vardenafil, 20mg tadalafil
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Is switching from a PDE inhibitor that isnt effective to another one effective?
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controversial, on study showed going from sildenafil to vardenafil was beneficial, but there needs to be more studies
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Should PDE inhibitors be used if normal erectile function?
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no
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Should PDE inhibitors be used in combo with any other tx?
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no, may lead to prolonged erections
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table 86-4 pg 1376
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table 86-4 pg 1376
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sildenafil
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Viagra
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vardenafil
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Levitra
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tadalafil
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Cialis
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What PDE isoenzymes does sildenafil inhibit?
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5 and 6
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What PDE isoenzymes does vardenafil inhibit?
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5, 6(minimally)
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What PDE isoenzymes does todalafil inhibit?
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5 and 11
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What is time to peak for sildenafil?
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0.5-1h
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What is time to peak for vardenafil?
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0.7-0.9h
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What is time to peak for tadalafil?
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2h
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Which PDE inhibitor has the longest half life?
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tadalafil, 18h compared to 3-5 for others
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Which PDE inhibitor is excreted the most in feces?
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vardenafil
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Which PDE inhibitor is excreted the least in feces?
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tadalafil
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Are PDE inhibitors excreted more in feces or urine?
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feces
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Which PDE inhibitor is excreted the most in urine?
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tadalafil
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Which PDE inhibitor is excreted the least in urine?
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vardenafil
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What is the duration of the PDE inhibitors?
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sildenafil and vardenafil are 4 hours, tadalafil is 24-36h
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Which PDE inhibitor can be given in severe hepatic impairment?
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sildenafil (25mg)
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Which PDE inhibitor doesn't require a lower dose in pts >/= 65?
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tadalafil
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What PDE inhibitor requires a dose reduction in moderate renal impairment?
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tadalafil
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Which PDE inhibitors require a dose adjustment in severe renal impairment?
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sildenafil and tadalafil
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Which PDE inhibitor requires a dose adjustment for mild hepatic impairment?
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tadalafil (10mg)
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Which PDE inhibitor requires a dose adjustment for moderate hepatic impairment?
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vardenafil (5-10) and tadalafil (10)
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What is dosage for PDE inhibitors if taking CYP3A4 inhibitors?
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sildenafil (25mg), vardenafil (2.5-5mg q24-72hrs), tadalafil (10mg q72h)
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Where is PDE 6 located and what can inhibition lead to?
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rods and cones of the eye, inhibition associated with blurred vision and cyanopsia
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Where is PDE 11 located and what can inhibition lead to?
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striated muscle, inhibition associated with myalgia and muscle pain
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Which PDE inhibitor offers greater spontaneity for pts because one dose can last through an entire weekend and allow for multiple acts of sexial intercourse with a single dose?
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tadalafil
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How long does it take for PDE inhibitors to work?
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50% may develop erection in 20-30 minutes from 100mg sildenafil, 20mg vardenafil, or 20mg tadalafil
the rest may take a full hour |
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What can happen if take PDE inhibitor with ethanol?
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orthostatic hypotension
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How are PDE inhibitors catabolized?
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CYP3A4
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If pt doesn't respond to on demand PDE inhibitor, what can be tried?
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regular daily dosing may improve endothelial function in cavernosal tissue
regular use may increase local concentrations of cGMP |
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Are AE of PDE inhibitors permanent?
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most are mild or moderate and self-limited, and pts often become tolerant to them with continued use
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What are the most common AE for PDE inhibitors?
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HA, facial flushing, dyspepsia, nasal congestion, dizziness, all of which result from vasodilation or smooth muscle relaxation secondary to inhibition of PDE 5 in extragenital tissues
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Which PDE inhibitors cause a decrease in BP and how much?
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sildenafil and vardenafil
8-10mm Hg systolic and 5-6mm Hg diastolic decrease 1hr after dose and lasting for 4 hrs |
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When should a pt undergo complete cv workup and treadmill stress test to determine tolerance to increasic myocardial energy consumption associated with increased sexual activity bevor being considered for PDE inhibitor?
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>/= 3 risk factors for CV disease
moderate stable angina MI or stroke in past 6 weeks moderate congestive heart failure |
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When are PDE inhibitors CI and sexual intercourse deferred?
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unstable or symptomatic angina despite tx
uncontrolled HTN severe congestive heart failure MI or stroke in past 2 weeks moderate or severe valvular heart disease high-risk cardiac arrhythmias obstructive hypertrophic cardiomyopathy |
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Why do airplane pilots have to be cautious when taking PDE inhibitors?
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can cause blue-green color discrimination from inhibition of PDE 6 (sildenafil and vardenafil)
usually at higher doses |
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What eye disorder should should cause all PDE inhibitors to be used cautiously?
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risk for retinitis pigmentosa
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What can sudden vision loss whiled taking a PDE inhibitor be a sign of?
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nonarteritic anterior ischemic optic neuropathy (NAION)
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What causes nonarteritic anterior ischemic optic neuropathy?
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the BP lowering decreases blood flow to the optic nerve and leads to sudden unilateral decrease in vision
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What pts are at risk of nonarteritic anterior ischemic optic neuropathy?
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glaucoma, macular degeneration, diabetic retinopathy, those who have undergone eye surgery, or experienced eye trauma
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What explains the lower back and limb muscle pain from tadalafil?
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PDE 11 inhibition
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Sildenafil inhibits PDE 5 in platelets, what AE?
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none
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Which PDE inhibitors cause more priapism?
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rare, sildenafil and vardenafil (shorter half life)
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What is the main DI with PDE inhibitors?
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nitrates
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What is there a DI with nitrates?
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severe hypotension:
nitrates on their own produce hypotension nitrates are nitric oxide donors which stimulate activity of guanylate cyclase and increase tissue levels of cGMP |
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How long after PDE inhibitor can you give nitrates?
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24hrs after sildenafil or vardenafil and 48hrs after tadalafil
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What should pt use if taking PDE inhibitor and need tx for angina?
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non-nitrate containing agents (CCB, BB, morphine)
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What is tx if take nitrate and PDE inhibitor and experience hypotension?
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Trendelenburg position and aggressive fluid administration
if continues, parenteral alpha adrenergic agonists (dopamine) |
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Do dietary sources of nitrates, nitrites, or L-arginine interact with PDE inhibitors?
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no because they dont increase levels of NO in humans
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Do PDE inhibitors interact with antihypertensive medications?
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no, same amount of hypotension experiences as PDE inhibitors alone
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When taking PDE inhibitors and alpha adrenergic antagonists together, how should they be taken?
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4 hour interval between doses of PDE inhibitors and alpha adrenergic antagonists
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Hepatic metabolism of all PDE inhibitors is inhibited by what?
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CYP3A4 inhibtors (cimetidine, erythromycin, clarithromycin, ketoconazole, itraconazole, ritonavir, saquinavir)
use a lower starting dose |
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What is normal range for testosterone levels?
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300-1100ng/dL
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How does testosterone replacement work for ED?
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directly stimulates androgen receptors in CNS and maintains normal sexual drive
also stimulates nitric oxide synthase, thereby increasing cavernosal concentrations of NO, enhances the effects of PDE type 5 in cavernosal tissue |
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How do you distinguish between primary or secondary hypogonadism?
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primary have elevated LH and secondary have decreased LH
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What is andropause?
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primary hypogonadism, characteristic of aging men, the Leydig cells of testes slowly and progressively decrease testosterone production
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Is testosterone replacement ever used if have normal serum testosterone?
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no
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Do testosterone replacement regimens directly correct ED?
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no, they improve libido
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How fast are testosterone levels corrected when using testosterone replacement?
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within days or weeks
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What routes is testosterone given?
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orally, perenterally, or transdermally
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Which route of testosterone is preferred?
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injectable: effective, inexpensive, and not associated with bioavailability problems or hepatotoxic AE of PO.
TD testosterone are much more expensive, use only if refuse injections |
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When are normal peaks and troughs of testosterone?
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peak early morning, trough late afternoon
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What are metabolites of testosterone?
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dihydrotestosterone and estradiol
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Does natural testosterone have good oral bioavailability?
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no because of extensive first pass hepatic metabolism, must take large doses
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What was done to testosterone to get better bioavailability?
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alkylated derivatives (methyltestosterone and fluoxymesterone)
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What is drawback of oral alkylated testosterone derivatives?
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higher incidence of serious hepatotoxicity
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What is an alternative to oral administration of testosterone?
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testosterone buccal system (Striant), it's applied to the gum above the upper incisor teeth BID, it forms a gel and it bypasses first pass hepatic catabolism which increases bioavailability
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What is the shortest acting IM testosterone?
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testosterone propionate, dosing 3x/week
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How are testosterone cypionate and enanthate dosed?
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every 2,4, or 6 weeks
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What is the longest acting testosterone injection?
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SQ testosterone, dosed every 4-6 months
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What is drawback of SQ testosterone?
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must be administered by physician and implant can be extruded after administration, may also cause mood swings from suprapharmacologic patterns of serum testosterone
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What advantage does patch have over injection or oral testosterone?
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produces physiologic pattern of serum testosterone
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How often are topical testosterone administered?
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daily
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How often for testosterone to reach normal range when using topical?
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2-6hrs
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How long for testosterone levels to return to baseline when using topical testosterone?
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24hrs after patch administration
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When is the testosterone patch applied?
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bedtime
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When is the testosterone gel applied?
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morning
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Where is the original Testoderm patch applied?
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scrotal application, it is thinner and has a richer vascular supply than arms or thighs, produces excellent absorption of hormone
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What is drawback of scrotal application?
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patch can fall off if scrotum is damp or moist, when pt exercises, or if scrotum is hairy
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Where can Androderm patches be applied?
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arms, buttocks, back, thighs
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Where can Testoderm TTS patches be applied?
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arms, buttocks, back
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Does Androderm or Testoderm scrotal patch cause more contact dermatitis?
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Androderm because of the addition of absorption enhancers and different adhesives
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What is strength of AndroGel?
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1%
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How much AndroGel is applied daily?
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much larger doses, 5-10g
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Where is AndroGel applied?
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shoulders, upper arms, abdomen
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How long for AndroGel to be absorbed?
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30 minutes, but may take several hours for complete absorption
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How long should pt wait after applying AndroGel before showering?
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5-6hrs
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What is considered and adequate tx trial of testosterone at a particular dose?
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2-3 months
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In pts over 40, what should be screened for before testosterone administration?
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BPH and prostate cancer
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What are AE of testosterone replacement?
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Na retention: wt gain, HTN, congestive heart failure, edema
Gynecomastia from conversion of testosterone to estrogen in peripheral tissues decreased HDL |
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What labs should be monitored if on long-term testosterone replacement?
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serum testosterone level, lipid profile, hct before starting and every 6-12 omnths
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What hct level is needed to withhold testosterone replacement?
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55%, to avoid polycythemia
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What is a serious AE that oral alkylated testosterone has caused?
|
hepatotoxicity
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Do patches or gel have more contact dermatitis?
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patch
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What is MOA of alprostadil?
|
prostaglandin E1
stimulates adenyl cyclase, resulting in increased production of cAMP, a secondary messenger that causes smooth muscle relaxation of the arterial blood vessels and sinusoidal tissues in the corpora. This results in enhanced blood flow to and blood filling of the corpora |
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What dosage forms of alprostadil are available?
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intracavernosal injection (Caverject and Edex) and intraurethral insert (medicated urethral system for erection, MUSE)
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What are indications for alprostadil?
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monotherapy for ED
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Is intracavernosal or intraurethral Alprostadil route more effective?
|
intracavernosal, because bioavailability is excellent when injected into corpora cavernosum
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Does intracavernosal or intraurethral Alprostadil have a higher dose?
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intraurethral dose is generally several hundred times larger than intracavernosal
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Are ther any other agents that have been used off-label for intracavernosal therapy?
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papaverine, phentolamine, atropine
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Why is alprostadil the preferred intracavernosal agent for ED?
|
FDA approved, doesn't require compounding, low potential for prolonged erections and priapism
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When should Alprostadil be used?
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when pt doesn't respond or can't use less invasive interventions (VED, PDE inhibitors)
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How is effectiveness of alprostadil related to dose?
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dose related, higher the dose the longer the erection (12-44 minutes)
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How do psychogenic and neurogenic ED respond to alprostadil compared to vasculogenic ED?
|
higher percent respond to lower doses of alprostadil
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Does tolerance develop from intracavernosal alprostadil?
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no
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What are the most common reasons for d/c of intracavernosal alprostadil?
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lack of perceived effectiveness, inconvenience of administration; unnatural, nonspontaneous erection; needle phobia; loss of interest; cost of therapy
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How often do pts not respond to usual doses of intracavernosal alprostadil?
|
1/3
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What is next if pt doesn't respond to intracavernosal alprostadil?
|
can use combo alprostadil with VEDs
can use intracavernosal injections of synergistic combinations of vasoactive agents (papaverine, phentolamine) |
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What is advantage of combination intracavernosal combos?
|
typically produces longer erection
fewer systemic and local fibrotic AE |
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What AE from papaverine is less likely when used in low dose combination?
|
hypotension and liver dysfunction
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What AE from phentolamine is less likely when used in low dose combination?
|
tachycardia and hypotension
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What is drawback of intracavernosal combination?
|
have to be compounded
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Where is intracavernosal injection injected?
|
ONE corpus cavernosum, the drug reaches the other corpus cavernosum through vascular communications between 2 corpora
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What is onset of action of alprostadil?
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5-15 minutes
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What is duration of excretion of alprostadil?
|
no more than 1hr at usual dosage, higher doses have a longer duration of action
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Is it a problem if any of the alprostadil escapes into systemic circulation?
|
no, it is deactivated on first pass through the lungs
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What is plasma half life of alprostadil?
|
1 minute
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Is alprostadil renal or hepatic dosed?
|
no
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When should intracavernosal alprostadil be given?
|
5-10 minutes before intercourse
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How is intracavernosal alprostadil dosed?
|
start with a 1.25mcg dose and increase in increments of 1.25mcg-2.5mcg at 30 minute intervals up to the lowest dose that produces a firm errection for 1hr and no AE
This is time consuming and physician usually starts at 10mcg and moves quickly up. |
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How often can intracavernosal alprostadil be given?
|
once a day, 3 days per week
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Where should intracavernosal alprostadil injection be given?
|
on the lateral surface of the proximal third of the penis, never on the dorsal or ventral surface to preven inadverten injection into arteries
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What should be done after the injection is made?
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masage penis to help distribute into opposite corpus cavernosum, rotate stie of injection, manual pressure should be applied to injection site for 5 minutes to reduce likelihood of hematoma.
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How often should pt return for followup when using intracavernosal alprostadil?
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every 3-6 months
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What are most common AE for intracavernosal alprostadil?
|
local AE (cavernosal plaques), penile pain, priapism
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What should be done if cavernosal plaques or fibrosis occur?
|
suspend further injections until plaques resolve, may cause penile curvature (similar to Peyronie disease)
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What should be used to treat pain from intracavernosal injections?
|
oral analgesics (APAP)
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What is Caverject?
|
commercially available alprstadil (acidic) that is buffered with sodium citrate (base) to reduce pain on injection
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When is the greatest risk for blood sludging in the corpora leading to tissue hypoxia and cavernosal fibrosis and scarring?
|
erections longer than 4hrs
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What is a urologic emergency?
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drug induced erections longer than 1hr, should seek medical attention
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How is priapism managed?
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supportive care (analgesics, sedatives), needle aspiration of sludged blood in corpora or intracavernosal injection of alpha adrenergic agonists (phenylephrine)
this facilitates venous drainage of corpora, allowing venout outflow to catch up with arterial inflow |
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What systemic AE from large doses of intracavernosal injections?
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dizziness and hypotension
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Who should use intracavernosal injection therapy cautiously?
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risk of priapism (sickle cell disease, lymphoproliferative disorders), bleeding complications (anticoagulants), poor quality injection technique (psychiatric disorders, obese pts, blind, arthritis)
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What is third line tx for ED?
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intraurethral alprostadil
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How fast is intraurethral alprostadil absorbed?
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90% absorbed in < 10minutes
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When is peak absorption of intraurethral absorption?
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20-25 minutes
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How much intraurethral alprostadil reaches the cavernosum?
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20%
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Does intraurethral alprostadil have systemic effect?
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no, rapidly metabolized on first pass through lungs
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What is onset of intraurethral alprostadil?
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5-10minutes
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When should intraurethral be administered?
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5-10 minutes before sexual intercourse
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How often can intraurethral alprostadil be given?
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BID
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What should pt do before administering intraurethral alprostadil?
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empty bladder
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How far is intraurethral applicator inserted into urethra?
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0.5 inches
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What AE from intraurethral alprostadil?
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urethra injury, urethral pain, priapism
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What rare systemic effects from high doses of intraurethral alprostadil?
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syncope and dizziness
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What effects might female partner experience from intraurethral alprostadil?
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vaginal burning, itching, or pain
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Are combos of proerctogenic drugs (sildenafil plus alprostadil) recommended by FDA?
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no, may cause priapism
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What depression medication can be used off label for ED?
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trazodone
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How does trazodone work for ED?
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antagonizes peripheraly alpha adrenergic receptors resulting in a predominant cholinergic effect, that causes peripheral arteriolar vasodilation and relaxation of cavernosal tissues, enhancing blood filling of corpora
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What AE from trazodone?
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dry mouth, sedation, dizziness
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Where does yohimbine come from?
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tree bark derviative
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What is MOA of yhimbine?
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central alpha 2 adrenergic antagonist that increases catecholamines and improves mood
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Is yohimbine effective?
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no, no more effective than placebo
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What AE from yohimbine?
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anxiety, insomnia, tachycardia, HTN
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What is MOA of papaverine?
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nonspecific PDE inhibitor that decreases metabolic catabolism of cAMP in cavernosal tissue
results in enhanced levels of cAMP, smooth muscle relaxation, cavernosal sinusoids fill with blood, penile erection results |
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Is papaverine FDA approved for ED?
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no
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Why is intracavernosal papaverine not used alone?
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large doses are required than produce dose related AE (priapism, corporal fibrosis, hypotension, and hepatotoxicity)
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How is papaverine usually given?
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low dose combined with phentolamine and/or alprostadil
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Is papaverine systemically absorbed?
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a portion is, and its prolonged half life increases AE
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How often do LFTs need to be run for pts taking papaverine with a history of underlying liver disease or alcohol abuse?
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6-12 months
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What is MOA of phentolamine?
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competitive nonselective alpha adrenergic blocking agen
It reduces peripheral adrenergic tone and enhances cholinergic tone. As a result, it improves cavernosal filling and is proerectogenic |
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Why is phentolamine not used as monotherapy?
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large doses required, systemic hypotensive AE
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How is phentolamine usually given?
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intracavernosal injection in combo with other vasoactive agents
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How is phentolamine usually dosed with papaverine?
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30mg papaverine to 0.5-1mg phentolamine
usual dose is 0.1-1mL of mixture |
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What is the purpose of the mixture of papavarine and phentolamine?
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promotes local effects of phentolamine and minimizes systemic hypotensive AE
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What is the most common AE of phentolamine?
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hypotension
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What is malleable prostheses?
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2 bendable rods inserted into corpora cavernose, permanent erection, can bend penis into position
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What is inflatable prosthesis?
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more natural erection, develops erection only when device is activated
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What is the most common early complication of prosthesis?
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infection
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What late complications may occur?
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mechanical failure, erosion of rods through penis, late onset infection
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What are steps for tx of failure to improve the quality and quantity of penile erections?
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1.ensure pt prescribed max tolerated dose and adequate clinical trial of specific tx before discarding as ineffective
2. switch to another drug, usually with more AE and complications 3. surgical tx for pts who do not respond to drug tx |
