Erectile Dysfunction Flashcards
what are the ED drug classes
- phosphodiesterase inhibitors
- alpha 2 antagonists
- prostaglandin E1 analogs
what is the suffix for ED therapeutic agents
-afil
which ED agent is a natural source
Yohimbine
what is the indication for sildenafil citrate
- ED
2. pulmonary arterial hypertension
what is the mechanism of action of sildenfafil citrate
PDE 5 inhibitor; sustains the vasodilatory effects of nitric oxide-dependent synthesis of cCMP
what is nitric oxide
a free radical produced in our body that can be toxic. benefits are that it is a vasodilator.
what does nitric oxide do
- inhibits platelet aggregation
- inhibits adhesion of monocytes
- inhibits LDL oxidation
- inhibits superoxide radical elaboration
- inhibits smooth muscle cell proliferation
NO activates gaunylate cyclase which converts GTP –> _____. Phosphodiesterase 5 promotes cGMP degradation.
cGMP
what is the aa which is a substrate by which NO is generated
L argenine
What activates phosphodiesterase
transducin
Our ability to see light depends on ______
phosphodiesterase
what are common adverse effects of sildenafil citrate
- headache
- abnormal vision
- dizziness
- nasal congestion
what are serious adverse effects of sildenafil citrate
- MI
- stroke
- ventricular tachycardia
- hyoptension/shock
- anemia
- leukopenia (loss of WBC)
what are ocular adverse effects
- retinal hemorrhage
- NAION: non arteritic ischemic optic neuropathy
- vision loss
- elevated IOP
- cyanopsia
why do you get ischemia from a drug that is a vasodilator
it doesn’t enhance perfusion of optic nerve head. If you get vasodilation everywhere else in body, the perfusion pressure in optic nerve is reduced to presence of lower pressures all around which creates ischemic event.
