Mechanism of Action - Pharmacy Freak

Mechanism of Action of Pepto-Bismol

April 29, 2026 Harsh Singh Rajput

Introduction Pepto-Bismol contains bismuth subsalicylate, an over-the-counter medication used for the treatment of diarrhea, dyspepsia, nausea, and upset stomach. It has multiple mechanisms of action including antimicrobial, anti-secretory, and mucosal protective effects. Its combination of bismuth and salicylate components contributes to its broad therapeutic activity in gastrointestinal disorders. Mechanism of Action (Step-wise) A key exam … Read more

Mechanism of Action of Pepcid (Famotidine)

April 29, 2026 Harsh Singh Rajput

Introduction Pepcid is the brand name for famotidine, a histamine H2 receptor antagonist used to reduce gastric acid secretion. It is commonly used in conditions such as gastroesophageal reflux disease (GERD), peptic ulcer disease, and dyspepsia. Famotidine works by blocking histamine-mediated stimulation of acid secretion in gastric parietal cells. Mechanism of Action (Step-wise) A key … Read more

Mechanism of Action of Pentoxifylline

April 29, 2026 Harsh Singh Rajput

Introduction Pentoxifylline is a hemorheologic agent used to improve blood flow, particularly in peripheral vascular diseases such as intermittent claudication. It enhances microcirculation by improving red blood cell flexibility and reducing blood viscosity. Unlike classic vasodilators, pentoxifylline primarily acts by modifying blood rheology and cellular properties. Mechanism of Action (Step-wise) A key exam point is … Read more

Mechanism of Action of Pantoprazole

April 28, 2026 Harsh Singh Rajput

Introduction Pantoprazole is a proton pump inhibitor (PPI) used in the treatment of acid-related disorders such as gastroesophageal reflux disease (GERD), peptic ulcer disease, and Zollinger–Ellison syndrome. It reduces gastric acid secretion by irreversibly inhibiting the proton pump in gastric parietal cells. Pantoprazole is highly effective in reducing both basal and stimulated acid secretion. Mechanism … Read more

Mechanism of Action of Oxymetazoline

April 28, 2026 Harsh Singh Rajput

Introduction Oxymetazoline is a topical decongestant and vasoconstrictor commonly used in nasal sprays and ophthalmic preparations. It is an imidazoline derivative that acts on adrenergic receptors to reduce mucosal congestion. It provides rapid relief in conditions such as allergic rhinitis, sinusitis, and nasal congestion. Mechanism of Action (Step-wise) A key exam point is that oxymetazoline … Read more

Mechanism of Action of Opiates

April 27, 2026 Harsh Singh Rajput

Introduction Opiates are a class of drugs derived from opium that produce potent analgesic effects. They act primarily on opioid receptors in the central and peripheral nervous system to relieve pain, produce sedation, and induce euphoria. Common examples include morphine, codeine, and heroin. Opiates are widely used for moderate to severe pain but are associated … Read more

Mechanism of Action of Noradrenaline

April 23, 2026 Harsh Singh Rajput

Introduction Noradrenaline (norepinephrine) is an endogenous catecholamine that functions as both a neurotransmitter and a hormone. It is widely used clinically as a vasopressor in conditions such as septic shock and acute hypotension. Noradrenaline primarily acts on α-adrenergic receptors with additional β1 receptor activity, leading to potent vasoconstriction and increased blood pressure. Mechanism of Action … Read more

Mechanism of Action of Sodium Nitroprusside

April 19, 2026 Harsh Singh Rajput

Introduction Sodium nitroprusside is a potent, rapid-acting vasodilator used primarily in hypertensive emergencies and acute heart failure. It produces both arterial and venous dilation, leading to a significant reduction in blood pressure. Due to its immediate onset and short duration of action, it is administered intravenously under close monitoring. Mechanism of Action (Step-wise) A key … Read more

Mechanism of Action of Nitrous Oxide

April 19, 2026 Harsh Singh Rajput

Introduction Nitrous oxide is an inhalational anesthetic gas with analgesic and sedative properties. It is widely used in anesthesia practice and procedural sedation, especially for short procedures. It has a rapid onset and recovery due to low blood solubility. Nitrous oxide provides good analgesia but relatively weak anesthetic potency, so it is often used in … Read more

Mechanism of Action of Nitroglycerin

April 19, 2026April 19, 2026 Harsh Singh Rajput

Introduction Nitroglycerin is an organic nitrate widely used in the management of angina pectoris and acute coronary syndromes. It acts as a potent vasodilator, primarily affecting venous capacitance vessels, thereby reducing cardiac workload. It also improves coronary blood flow and relieves ischemic chest pain. Nitroglycerin is considered a cornerstone drug for rapid relief of angina. … Read more