Nitroglycerin
vasodilator
Uses
appears to releive symptoms, not reduce events.
Mechanism
- nitric oxide relaxes smooth muscle, leading to vasodilation, especially in veins
- increased venous pooling leads to decreased preload and wall stress
- at higher doses, lowered BP can desult in tachycardia
- dilates coronary arteries
Dose and Half Life
sublingual tabs or spray
- used for attacks of angina, or prophylactically
- short acting; onset 1-5 minutes, duration 15-30 mins
- use this first in emergencies
- oral administration leads to liver metabolism
- IV in emergencies
- transdermal patch provides 8-12 hours of activity
Adverse Drug Reactions
short term
- headaches
- reflex increase in heart rate due to baroreceptor response (tachyphylaxis)
- high degree of tolerance over time
long term
Counter-Indications and Drug Interactions
- can cause profound hypotension if used with sidenafil (Viagra)
Metabolism and Excretion
Dependency