Vasodilators Flashcards
Oral vasodilators for long term outpatient therapy of hypertension
Hydralazine and minoxidil
Parenteral vasodilators used to treat hypertensive emergencies
Nitroprusside, diazoxide, and fenoldopam
Vasodilators used for long term outpatient therapy and hypertensive emergencies.
Ca channel blockers
Vasodilators mainly used for angina
Nitrates
Vasodilators that relax also veins
Na nitroprusside and nitrates
Using these drugs will not cause orthostatic hypertension or sexual dysfunction because sympathetic reflexes are intact
Vasodilators
Dilates arterioles but not veins. Tachyphylaxis. Used particularly in severe hypertension and combined with nitrates for patients with both hypertension and heart failure especially in african american patients
Hydralazine
Well absorved and rapidly metabolized by the liver. Metabolized in part by acetylation and vascular effects persisit longer than blood concentrations due to avid binding to vascular tissue
Hydralazine
Most common side effects of hydralazine
Headache, nausea, anorexia, palpitations, sweating and flushing
Reflex tachycardia and sympathetic stimulation may provoke angina or ischemic arrhythmias in patients with ischemic heart disease
Hydralazine
Produces lupus erythematosus like symptoms at dosages of 400 mg/d or more
Hydralazine
Serious but uncommon side effects of hydralazine
Peripheral neuropathy and drug fever
Hyperpolarizes smooth muscle membrane through opening of K channels causing the vessel to be stabilized and contraction less likely
Minoxidil and diazoxide
Should replace hydralazine when maximal doses are not effective or in patients with renal failure and severe hypertension who do not respond well to hydralazine. Also dilates arterioles and not veins just like hydralazine
Minoxidil
Must be used in combination with a B blocker and a loop diuretic
Minoxidil(but i guess all of vasodilators must be combined with these drugs)
Headache, sweating, and hypertrichosis which are particularly bothersome to women are relatively common with the use of this drug. Rogain is used a stimulant for hair growth in the correction of baldness.
Minoxidil
Powerful parenterally administered vasodilator used in treating hypertensive emergencies as well as severe heart failure. Dilates both arterial and venous vessels resulting in reduced PVR and venous return.
Na nitroprusside
Rapidly metabolized onto RBC liberating cyanide
Na nitroprusside
Sensitive to light and must therefore made up fresh before administration and covered with opaque foil.
Na nitroprusside
Most serious toxicity is associated with accumulation of cyanide. Metabolic acidosis, arrhythmias, excessive hypotension, and death.
Na nitroprusside
Advocated for prophylaxis or treatment for cyanide poisoning during nitroprusside infusion.
Na thiosulfate
Hydroxocobalamine
Can cause thiocyanate toxicity manifested as weakness, disorientation, psychosis, muscle spasms, and convulsions. Rarely delayed hyperthyroidism occurs and methemoglobinemia.
Na nitroprusside
Effective and relatively long acting parenterally administered arteriolar dilator occasionally used to treat hypertensive emergencies
Diazoxide
Similar chemically to thiazide diuretics but has no diuretic activity. Hypotensive effects are greater when patients are pretreated with B blockers to prevent reflex tachycardia and associated increase in cardiac output
Diazoxide
Most significant toxicity of this drug is excessive hypotension that has resulted in stroke and MI.
Diazoxide
Reflex sympathetic response can provoke angina, electrocardiographic evidence of ischemia, and cardiac failure in patients with ischemic heart disease and should be avoided in this situation.
Diazoxide
Inhibits insulin release from the pancreas and is used to treat hypoglycemia secondary to insulinoma. Can also cause renal salt and water retention.
Diazoxide
Peripheral arteriolar dilator used for hypertensive emergencies and postoperative hypertension. Agonist of dopamine D1 receptors resulting in dilation of peripheral arteries and natriuresis. R isomer mediates pharmacologic activity
Fenoldopam
Major toxicities of this drug are reflex tachycardia, headache, flushing, and can inrease intraocular pressure and should be avoided in patients with glaucoma.
Fenoldopam