Guanethidine 4959500 210101051 2008-05-04T13:33:21Z 77.103.112.47 {{drugbox | IUPAC_name = 2-(2-azocan-1-ylethyl)guanidine | image = Guanethidine.svg | CAS_number = 645-43-2 | ATC_prefix = C02 | ATC_suffix = CC02 | ATC_supplemental = {{ATC|S01|EX01}} | PubChem = 3518 | DrugBank = APRD01007 | C=10 | H=22 | N=4 | molecular_weight = 198.309 g/mol | bioavailability = | protein_bound = | metabolism = | elimination_half-life = 1.5 days | pregnancy_category = | legal_status = | routes_of_administration = }} '''Guanethidine''' is an [[antihypertensive]] drug that reduces the release of [[catecholamines]], such as noradrenaline. Its mechanism is inhibition of the [[Mg++ATPase dependent pump]]. Side effects include orthostatic and exercise hypotension, sexual dysfunction, and diarrhea. It is no longer available in the US due to side effects and because substantially better drugs are available. It is still licensed in some countries, e.g. UK, for the rapid control of blood pressure in a [[hypertensive emergency]]. Guanethidine is transported by uptake 1 into the presynaptic terminal. (In this it competes with noradrenaline so can potentiate exogenously applied noradrenaline). Once inside the terminal it blocks the release of noradrenaline in response to arrival of an action potential. Spontaneous release is not affected. Intravenous nerve block ([[Bier block]]) using guanethidine can be used to treat [[chronic pain]] caused by [[complex regional pain syndrome]]. {{Antihypertensives and diuretics}} {{Antiglaucoma preparations and miotics}} {{antihypertensive-stub}} [[de:Guanethidin]] [[hu:Guanethidin]] [[pl:Guanetydyna]]