adrenergic neuron blocker

definition

drugs inhibiting release of noradrenaline from sympathetic nerve endings

drugs depleting noradrenaline from sympathetic nerve ending

guanethidine

inhibits the release of noradrenaline from sympathetic nerve endings leading to reduction of the sympathetic tone - VD and marked drop in BP

severe postural and exertional hypotension

reserpine

depletion of catecolamines both central from brain and peripheral from the sympathetic nerve endings leading to lowering of the blood pressure

parkinsonism - nightmares - psychic - depression with suicidal attempts

alpha 2 agoinsts

clonidine - methyldopa - guanfacine - guanabenz

inhibit noradrenaline release

used in hypertension

imidazoline receptor agonists (I1)

rilmenidine - moxonidine

stiimulate I1 receptors in brain stem → decreasing VMC → sympathetic outflow → decreasing NA release → VD → decreasing BP

used in hypertension

ganglion blocker

trimethaphan →

only one used clinically

IV infusion

emergency hypotension or controlled hypotension