Class 2 Antiarrhythmic Drugs (Beta Blockers)
Chemistry and Pharmacodynamics Definition Class 2 antiarrhythmics include beta-blockers, which competitively inhibit epinephrine and norepinephrine from binding to the beta-adrenergic receptors on vascular and cardiac cells. Chemical structure Mechanism of action Physiologic effects Adrenergic receptor types and their properties Table: Adrenergic receptor types and their properties Receptor location Response to stimulus Response to blockade B1 […]
Movement Disorder Drugs
Overview Definition Movement disorders are a group of neurologic conditions that cause excessive voluntary or involuntary movements; these disorders can also cause reduced or slow movements. Classification Essential Tremor Definition Essential tremor, also called familial tremor, causes a benign postural tremor of the hands that can cause significant distress for individuals who are affected by […]
Antivirals for Hepatitis C
Overview Hepatitis C virus (HCV) Single-stranded RNA virus Family: Flaviviridae Transmitted via: Parenteral Blood and blood products Intravenous drug use Perinatal Sexual intercourse Infection can lead to: Acute and chronic hepatitis Cirrhosis Hepatocellular carcinoma (HCC) Viral proteins Hepatitis C virus RNA encodes: 3 structural proteins: Core (contains viral RNA) Envelope 1 (E1) and envelope 2 […]
Local Anesthetics
Chemistry and Pharmacodynamics Chemical structure Mechanism of action Physiologic effects Pharmacokinetics Absorption Distribution Metabolism Excretion Pharmacokinetics of commonly used local anesthetics Table: Pharmacokinetics of commonly used local anesthetics Agent Half-life (adults) Onset of action Metabolism Excretion Cocaine 30 minutes to 1.5 hours 15–30 seconds Hydrolysis: spontaneous and by plasma pseudocholinesterase; hepatic Renal Benzocaine Short (exact […]
Antidiarrheal Drugs
Overview Diarrhea Diarrhea is the passage of ≥ 3 loose or liquid stools within 24 hours. Classification: General management: Drug classes Antidiarrheal properties These drug classes may improve symptoms of diarrhea via: Opioid Agonists Medications within this class The opioid agonists utilized for their antidiarrheal activity are: Mechanism of action Pharmacokinetics Loperamide: Diphenoxylate: Indications Adverse […]
Thyroid Replacement Therapy
Overview Pathophysiology of hypothyroidism Medical condition defined by deficiency of thyroid hormones: Thyroxine (T4) Triiodothyronine (T3) These hormones play an integral role in various functions: Metabolism Growth and development Catecholamine function Pituitary hormone synthesis regulation (feedback loop) Clinically, a deficiency in these hormones can lead to abnormal changes in: Energy levels Weight Thermoregulation HR Bowel […]
Antithyroid Drugs
Overview Pathophysiology of hyperthyroidism Medical condition defined by overproduction of hormones by the thyroid gland: Triiodothyronine (T3) Thyroxine (T4) Results in ↓ production of thyroid-stimulating hormone (TSH) by the pituitary gland. Antithyroid agents may be used as treatment by blocking: Thyroid hormone synthesis Conversion of T4 → T3 Thyroid hormone release Antithyroid medications Thionamides Methimazole […]
Gastric Acid Drugs
Overview Physiology of acid secretion Parietal cells are located in the body of the stomach and secrete hydrochloric acid (HCl) into the lumen. Water and CO₂ are combined to produce hydrogen (H+) ions and HCO₃ ions by the action of the carbonic anhydrase enzyme. H+ is transported to the lumen of the stomach via the […]
Cardiac Glycosides
Chemistry and Pharmacodynamics Chemical structure Digoxin is the prototype drug of the cardiac glycoside class and the only drug in the class used for medicinal purposes. Mechanism of action Physiologic effects Pharmacokinetics Absorption Distribution Metabolism and excretion Indications Heart failure Arrhythmia Digoxin is indicated for rate control when other therapies are ineffective or contraindicated: Adverse […]
Opioid Analgesics
Pharmacodynamics Definitions Opioids are a class of natural or synthetic drugs that act on opioid receptors to provide analgesia and CNS effects. Mechanism of action Opioid receptors The following table summarizes and compares the effects of opioid receptors: Table: Opioid receptor subtypes Mu (μ) receptor Kappa (κ) receptor Delta (δ) receptor Effect on analgesia Spinal […]