II. Background

  1. Adrenergic Receptor agonists increase Blood Pressure
    1. Alpha 1 Adrenergic Receptor binding increases Vasoconstriction
    2. Beta 1 Adrenergic Receptor binding increases myocardial contractility
  2. Presynaptic Adrenergic Release Inhibitors lower Blood Pressure
    1. Central Acting Adrenergic Agonists
      1. Activate alpha-2 receptors that inhibit CNS sympathetic signals
      2. Results in increased parasympathetic effects and side effects
    2. Peripheral Acting Adrenergic Antagonists
      1. Block peripheral Norepinephrine release

III. Preparations: Peripheral Acting Adrenergic Antagonists

  1. Mechanism
    1. Peripheral Acting Adrenergic Antagonists block Norepinephrine release from postganglionic nerve terminals
  2. Agents
    1. Reserpine (Serpasil)
    2. Guanethidine (Ismelin)
    3. Guanadrel (Hylorel)

IV. Preparations: Central Acting Adrenergic Agonists

  1. Mechanism
    1. See Alpha Adrenergic Receptor
    2. Bind central alpha-2 receptors (vasomotor receptors) to inhibit sympathetic outflow
      1. Decreases peripheral vascular resistance (and Blood Pressure)
      2. Decreases Heart Rate
  2. Preparations
    1. Clonidine (Catapres)
    2. Methyl-Dopa (Aldomet)
    3. Guanabenz (Wytensin)

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Cost: Medications

Methyldopa (on 6/18/2017 at Walmart.com)
Methyldopa 250mg #60 tablets for $4.00 $0.07 each
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Ontology: Guanabenz (C0018312)

Definition (MSH) An alpha-2 selective adrenergic agonist used as an antihypertensive agent.
Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D006143
SnomedCT 372867002, 82951001
English 2,6-Dichlorobenzylideneaminoguanidine, Guanabenz, 2,6 Dichlorobenzylideneaminoguanidine, Hydrazinecarboximidamide, 2-((2,6-dichlorophenyl)methylene)-, guanabenz, Guanabenz [Chemical/Ingredient], GUANABENZ, Guanabenz (product), Guanabenz (substance)
Swedish Guanabenz
Czech guanabenz
Finnish Guanabentsi
Japanese グアナベンツ, グアナベンズ
Polish Guanabenz
Spanish guanabenz (producto), guanabenz (sustancia), guanabenz, Guanabenzo
French Guanabenz
German Guanabenz
Italian Guanabenzo
Portuguese Guanabenzo

Ontology: Wytensin (C0018313)

Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D006143
English Wyeth-Ayerst of Guanabenz Acetate, Wyeth Ayerst of Guanabenz Acetate, Acetate Wyeth-Ayerst, Guanabenz, Guanabenz Acetate Wyeth-Ayerst, Wytensin

Ontology: Guanethidine (C0018318)

Definition (MSH) An antihypertensive agent that acts by inhibiting selectively transmission in post-ganglionic adrenergic nerves. It is believed to act mainly by preventing the release of norepinephrine at nerve endings and causes depletion of norepinephrine in peripheral sympathetic nerve terminals as well as in tissues.
Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D006145
SnomedCT 387456007, 79305004
English Guanethidine, Octadine, Oktadin, ((2-Hexahydro-1(2H)-azocinyl)ethyl)guanidine, guanethidine, Guanidine, (2-(hexahydro-1(2H)-azocinyl)ethyl)-, guanethidines (medication), guanethidines, Octatensine, (2-(Octahydro-1-azocinyl)ethyl)guanidine, Guanethidine [Chemical/Ingredient], Guanethidine (product), Guanethidine (substance), GUANETHIDINE
Swedish Guanetidin
Czech guanethidin
Finnish Guanetidiini
Japanese グアネチジン, 硫酸グアネチジン
Polish Guanetydyna, Ismelina
Spanish guanetidina (producto), guanetidina (sustancia), guanetidina, Guanetidina
French Guanéthidine
German Guanethidin
Italian Guanetidina
Portuguese Guanetidina

Ontology: Methyldopa (C0025741)

Definition (NCI) A phenylalanine derivative and an aromatic amino acid decarboxylase inhibitor with antihypertensive activity. Methyldopa is a prodrug and is metabolized in the central nervous system. The antihypertensive action of methyldopa seems to be attributable to its conversion into alpha-methylnorepinephrine, which is a potent alpha-2 adrenergic agonist that binds to and stimulates potent central inhibitory alpha-2 adrenergic receptors. This results in a decrease in sympathetic outflow and decreased blood pressure.
Definition (MSH) An alpha-2 adrenergic agonist that has both central and peripheral nervous system effects. Its primary clinical use is as an antihypertensive agent.
Concepts Pharmacologic Substance (T121) , Neuroreactive Substance or Biogenic Amine (T124) , Amino Acid, Peptide, or Protein (T116)
MSH D008750
SnomedCT 373542000, 84078002
LNC LP16200-5, MTHU016766
English Alphamethyldopa, alpha Methyl L Dopa, alpha Methyldopa, alpha-Methyl-L-Dopa, alpha-Methyldopa, methyldopa, L-Tyrosine, 3-hydroxy-alpha-methyl-, 3-Hydroxy-alpha-methyl-L-tyrosine, L-2-Amino-2-methyl-3-(3,4-dihydroxyphenyl)propionic Acid, Levo-3-(3,4-Dihydroxyphenyl)-2-methylalanine, O methyl DOPA, methyldopa (medication), Methyldopa [Chemical/Ingredient], alphamethyldopa, alpha-methyldopa, alpha methyldopa, METHYLDOPA, Methyldopa, Alpha methyldopa, Methyldopa (product), Methyldopa (substance)
Swedish Metyldopa
Czech methyldopa
Finnish Metyylidopa
Japanese α-メチルドーパ, メチルドパ, メチルドーパ, アルファ-メチルドーパ
Spanish alfa-Metildopa, metildopa (producto), metildopa (sustancia), metildopato, metildopa, Metildopa
French alpha-Méthyldopa, alpha-L-Méthyldopa, Méthyldopa
Polish Metylodopa
German Alphamethyldopa, Methyldopa
Italian Metildopa
Portuguese alfa-Metildopa, Metildopa

Ontology: Reserpine (C0035179)

Definition (NCI) An alkaloid, derived from the roots of Rauwolfia serpentine and vomitoria, and an adrenergic uptake inhibitor with antihypertensive effects. Reserpine is lipid soluble and can penetrate blood-brain barrier. This agent binds and inhibits catecholamine pump on the storage vesicles in central and peripheral adrenergic neurons, thereby inhibiting the uptake of norepinephrine, dopamine serotonin into presynaptic storage vesicles. This results in catecholamines and serotonin lingering in the cytoplasm where they are destroyed by intraneuronal monoamine oxidase, thereby causing the depletion of catecholamine and serotonin stores in central and peripheral nerve terminals. Depletion results in a lack of active transmitter discharge from nerve endings upon nerve depolarization, and consequently leads to a decreased heart rate and decreased arterial blood pressure as well as sedative effects.
Definition (MSH) An alkaloid found in the roots of Rauwolfia serpentina and R. vomitoria. Reserpine inhibits the uptake of norepinephrine into storage vesicles resulting in depletion of catecholamines and serotonin from central and peripheral axon terminals. It has been used as an antihypertensive and an antipsychotic as well as a research tool, but its adverse effects limit its clinical use.
Definition (CSP) alkaloid isolated from the root of Rauwolfia species, used as an antihypertensive and sedative.
Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D012110
SnomedCT 363523003, 387447004, 78379001
English Reserpine, Yohimban-16-carboxylic acid, 11,17-dimethoxy-18-((3,4,5-trimethoxybenzoyl)oxy)-, methyl ester, (3beta,16beta,17alpha,18beta,20alpha)-, (3beta,16beta,17alpha,18beta,20alpha)-11,17-Dimethoxy-18-[(3,4,5-trimethoxybenzoyl)oxy]yohimban-16-carboxylic Acid Methyl Ester, reserpine, reserpine (medication), Reserpine [Chemical/Ingredient], RESERPINE, Reserpine - chemical, Reserpine - chemical (substance), Reserpine (product), Reserpine (substance)
Swedish Reserpin
Czech reserpin
Finnish Reserpiini
Japanese レセルピン
Polish Rezerpina, Serpazyl
Spanish reserpina - sustancia química (sustancia), reserpina - sustancia química, reserpina (producto), reserpina (sustancia), reserpina, Reserpina
French Réserpine
German Reserpin
Italian Reserpina
Portuguese Reserpina

Ontology: guanadrel (C0061938)

Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH C004945
SnomedCT 372820001, 69204002
English (1,4-dioxaspiro(4.5)dec-2-ylmethyl)guanidine, guanadrel, guanadrel [Chemical/Ingredient], Guanadrel, Guanadrel (product), Guanadrel (substance), GUANADREL
Spanish guanadrel (producto), guanadrel (sustancia), guanadrel

Ontology: Central alpha-adrenoceptor agonist (C0360167)

Concepts Pharmacologic Substance (T121)
SnomedCT 349933002, 372623002
English Central alpha-adrenocep agon., Central alpha-adrenoceptor agonist, Central alpha-adrenoceptor agonist (product), Central alpha-adrenoceptor agonist (substance)
Spanish agonista central alfa adrenérgico (producto), agonista central alfa adrenérgico (sustancia), agonista central alfa adrenérgico, agonista de adrenorreceptor alfa central (sustancia), agonista de adrenorreceptor alfa central

Ontology: Aldomet (C0591055)

Concepts Pharmacologic Substance (T121) , Amino Acid, Peptide, or Protein (T116)
MSH D008750
English aldomet, Aldomet, Biopat Brand of Methyldopa, Cahill May Roberts Brand of Methyldopa, Merck Brand of Methyldopa, Merck Sharp & Dohme Brand of Methyldopa, Methyldopa Biopat Brand, Methyldopa Merck Brand

Ontology: Ismelin (C0701214)

Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D006145
English guanethidine sulfate (Ismelin), Ismelin

Ontology: Hylorel (C0720982)

Concepts Organic Chemical (T109) , Pharmacologic Substance (T121)
MSH C004945
English Hylorel, Celltech brand of guanadrel sulfate

Ontology: Serpasil (C0729168)

Concepts Organic Chemical (T109) , Pharmacologic Substance (T121)
MSH D012110
English Serpasil