Introduction Antacids are weakly basic compounds that neutralize excess gastric acid in the stomach, providing rapid relief from heartburn, acid reflux, gastritis, and peptic ulcer disease. Mechanism of Action of Antacids involves a direct chemical reaction with hydrochloric acid (HCl) in gastric juice to form salt and water, thereby increasing gastric pH and reducing acidity. … Read more
Introduction Amitriptyline is a tricyclic antidepressant (TCA) primarily used in the management of major depressive disorder, neuropathic pain, migraine prophylaxis, and insomnia. Mechanism of Action of Amitriptyline involves inhibition of serotonin (5-HT) and norepinephrine (NE) reuptake at presynaptic nerve terminals, thereby increasing their synaptic concentrations. Additionally, it exhibits significant anticholinergic, antihistaminic, and alpha-adrenergic blocking effects, … Read more
Introduction Amiloride is a potassium-sparing diuretic that acts on the distal nephron of the kidney to promote sodium excretion while conserving potassium. Mechanism of Action of Amiloride involves direct inhibition of epithelial sodium channels (ENaC) in the late distal tubule and collecting duct, leading to decreased sodium reabsorption and reduced potassium excretion. Unlike aldosterone antagonists … Read more
Introduction Amikacin is a broad-spectrum aminoglycoside antibiotic primarily used to treat severe Gram-negative bacterial infections, including those resistant to other aminoglycosides. Mechanism of Action of Amikacin involves irreversible inhibition of bacterial protein synthesis by binding to the 30S ribosomal subunit, leading to misreading of mRNA and defective protein formation. Because of its stability against many … Read more
Introduction Ambroxol is a mucolytic and expectorant agent widely used in the treatment of respiratory tract disorders associated with excessive or viscous mucus, such as bronchitis, COPD, and asthma. Mechanism of Action of Ambroxol involves enhancing mucus clearance, stimulating surfactant production, and improving mucociliary transport. It not only facilitates expectoration but also exerts anti-inflammatory and … Read more
Introduction Alprazolam is a short-acting benzodiazepine widely prescribed for anxiety disorders, panic attacks, and generalized anxiety disorder (GAD). Mechanism of Action of Alprazolam involves potentiation of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) at the GABA-A receptor, resulting in sedation, anxiolysis, and muscle relaxation. Known by its common brand name Xanax, alprazolam has a rapid onset … Read more
Introduction Alpha-adrenergic blockers, also called alpha-blockers, are a class of drugs that antagonize the effects of catecholamines (epinephrine and norepinephrine) at alpha-adrenergic receptors. Mechanism of Action of Alpha-Adrenergic Blockers involves inhibition of alpha-1 and/or alpha-2 receptors, resulting in vasodilation, decreased peripheral vascular resistance, and reduced blood pressure. These drugs are commonly used in the management … Read more
Introduction Allopurinol is a xanthine oxidase inhibitor used primarily in the management of gout and hyperuricemia associated with malignancy or chemotherapy. Mechanism of Action of Allopurinol involves inhibition of uric acid production by blocking the enzyme xanthine oxidase, thereby reducing serum uric acid levels and preventing crystal deposition in joints and tissues. It is a … Read more
Introduction Aldosterone is a mineralocorticoid hormone synthesized in the zona glomerulosa of the adrenal cortex. It plays a vital role in maintaining electrolyte balance, blood volume, and blood pressure through regulation of sodium and potassium homeostasis. Mechanism of Action of Aldosterone involves binding to intracellular mineralocorticoid receptors (MR) in epithelial cells of the distal nephron, … Read more
Introduction Ethanol, commonly referred to as alcohol, is a psychoactive substance and central nervous system (CNS) depressant with widespread social and clinical significance. Mechanism of Action of Alcohol involves modulation of several neurotransmitter systems—most notably GABA, glutamate, and dopamine—leading to sedation, euphoria, impaired motor coordination, and cognitive effects. Ethanol’s pharmacological effects depend on dose, chronicity … Read more
