Introduction Labetalol is a non-selective beta‑adrenergic antagonist with additional alpha‑1 blocking activity. It is commonly employed in the management of hypertension, particularly during acute hypertensive emergencies, and in certain forms of arrhythmia. The drug exhibits a unique pharmacologic profile that allows for both reduction of cardiac output and vasodilation, thereby providing a balanced cardiovascular effect….
1. Introduction Definition and Overview Dobutamine is a synthetic catecholamine that functions primarily as a β1-adrenergic agonist with comparatively weaker β2 and α1 activity. It is conventionally administered intravenously to augment myocardial contractility and cardiac output in conditions of reduced cardiac performance. The drug’s utility spans acute heart failure, cardiogenic shock, and cardiac stress testing….
Introduction Isoprenaline (also known as isoproterenol) is a synthetic catecholamine that functions primarily as a non‑selective beta‑adrenergic agonist. Its pharmacological profile encompasses activation of β1 and β2 adrenergic receptors, leading to pronounced cardiovascular, pulmonary, and metabolic effects. Historically, isoprenaline was first synthesized in the early 20th century and introduced clinically in the 1940s as a…
Introduction Dobutamine is a synthetic catecholamine analog frequently employed in cardiovascular therapeutics, particularly for the management of acute heart failure and cardiogenic shock. Its pharmacologic profile is characterized by predominant β1-adrenergic agonism with ancillary β2 and α1 receptor activity, culminating in enhanced myocardial contractility, modest vasodilatory effects, and a reduction in systemic vascular resistance. The…
Introduction Clonidine is an imidazoline derivative that has been employed therapeutically for several decades. The drug exhibits a selective agonistic effect on alpha‑2 adrenergic receptors and possesses modest affinity for imidazoline I1 receptors, resulting in a pronounced central sympatholytic action. Since its introduction in the 1950s as an antihypertensive agent, clonidine has expanded to a…
Introduction Phenylephrine is a selective α1-adrenergic receptor agonist that has been widely employed as a sympathomimetic agent for its potent vasoconstrictive properties. Historically, phenylephrine was first isolated in the early 20th century from the roots of the Rhododendron species and subsequently synthesized in the laboratory, enabling its mass production and diverse therapeutic applications. Phenylephrine’s pharmacological…
Introduction Definition and Overview Edrophonium, also known as Tetraethylammonium chloridate or by the trade name Tensilon, is a synthetic quaternary ammonium compound that functions as a short‑acting acetylcholinesterase inhibitor. The drug reversibly binds to the active site of acetylcholinesterase, thereby increasing the concentration of acetylcholine at cholinergic synapses. The pharmacologic profile of edrophonium is characterized…
Introduction Definition and Overview Bethanechol (C₁₀H₁₇NO₃) is a synthetic cholinergic agonist that selectively stimulates muscarinic acetylcholine receptors, predominantly the M₃ subtype. It possesses a structural resemblance to acetylcholine but is resistant to cholinesterase hydrolysis, thereby prolonging its action on target tissues. Bethanechol is commonly employed to enhance smooth muscle contractility in the urinary bladder and…
Introduction Definition and Overview Flumazenil is a selective antagonist at the benzodiazepine binding site on the gamma-aminobutyric acid type A (GABAA) receptor complex. It competitively inhibits the action of benzodiazepines and related agents, thereby reversing their sedative, anxiolytic, anticonvulsant, and muscle relaxant effects. The drug is administered intravenously, typically in a hospital setting, and is…
Introduction Dimercaprol, also known as British anti-Lewisite (BAL), represents a pivotal member of the class of dithiol chelating agents employed in the treatment of heavy‑metal intoxication. The compound is chemically designated as 3,3′-dithiodipropionic acid bis(2-ethylhexyl ester), and its therapeutic activity is largely attributable to the presence of two sulfhydryl groups capable of forming stable complexes…