Antivirals for Herpes Virus
Overview Human herpesviruses (HHVs) Antiherpes agents Nucleoside Analogs Chemical structure Pharmacodynamics Acyclovir: Pharmacokinetics Indications Acyclovir (and other related agents): Adverse events and contraindications Acyclovir: Comparison of nucleoside analogs Table: Comparison of nucleoside analogs against herpesviruses Agent Characteristics and mechanism of action Pharmacokinetics Approved indication Adverse drug effects Acyclovir Nucleoside analog Polymerase inhibitor Poor oral bioavailability […]
Antivirals for Influenza
Overview Influenza Virus strains are classified by the core proteins (A, B, C). Seasonal influenza is an illness caused by influenza A or B virus. Influenza is often a self-limited infection, but those at risk for complications can have significant morbidity and mortality. Antiviral drugs are available for prevention and treatment of influenza. Mechanism of […]
Class 5 Antiarrhythmic Drugs
Overview Vaughan-Williams classification This is the most commonly used classifications for antiarrhythmic drugs. There are 5 classes based on the drug class’s general effect (mechanism of action): Digoxin Mechanism of action Pharmacokinetics Indications Adverse effects Contraindications Drug interactions Adenosine Chemistry Adenosine is a naturally occurring purine nucleoside base. Mechanism of action Cardiac nodal cells: Vascular […]
Class 1 Antiarrhythmic Drugs (Sodium Channel Blockers)
Overview Cardiac action potential The trajectory followed by the action potential depends on the membrane potential of cardiac cells, which varies between different parts of the heart. Phase 4: resting potential Phase 0: rapid depolarization phase that occurs because of the influx of Na ions through voltage-dependent Na channels Phases 1‒3: Represent repolarization Prominent efflux […]
Hypertension Drugs
Overview Etiology Pathophysiology Classes of antihypertensive medications Current guidelines American Heart Association and American College of Cardiology guidelines (2017, 2021): Eighth Joint National Committee (JNC 8, 2014) guidelines: Selection of antihypertensive agent should be based on: Classification of hypertension Table: Classification of hypertension (2017 JNC 8 guidelines) BP category Systolic BP (mm Hg) Diastolic BP […]
Serotonin Reuptake Inhibitors and Similar Antidepressants
Chemistry and Pharmacodynamics Mechanisms of action Pharmacodynamics Pharmacokinetics Secondary serotonin reuptake inhibitors Serotonin-norepinephrine reuptake inhibitors Serotonin antagonist and reuptake inhibitor = trazodone (nefazodone is not currently available in the US) Serotonin modulator and stimulator = vortioxetine 5-Hydroxytryptamine1A receptor partial agonist = vilazodone Classification and Indications Antidepressant medications that affect serotonin levels in the brain to […]
Nonhormonal Contraception
Overview Classification Nonhormonal contraception can be classified into: Physiologic methods: Withdrawal/coitus interruptus Fertility awareness method (FAM): Rhythm method Basal body temperature method Cervical mucus method Lactational amenorrhea Abstinence from all sexual activity Barrier methods: Condom (male or female) Spermicide Contraceptive sponge Diaphragm Vaginal pH regulator gel Copper intrauterine device Surgical methods: Tubal occlusion or salpingectomy […]
First-Generation Antipsychotics
Chemistry and Pharmacodynamics Neurotransmitters that may be modulated by antipsychotics for a therapeutic effect include dopamine, serotonin (also called 5-hydroxytryptamine (5-HT)), and norepinephrine (NE). Mechanism of action Blockade of postsynaptic dopamine D2 receptors in the mesolimbic pathway → relief of psychotic symptoms Blockade in mesocortical, nigrostriatal, and tuberoinfundibular pathways → adverse effects Low-potency agents have […]
Antimycobacterial Drugs
Overview Definition Antimycobacterial agents represent a diverse group of compounds used against mycobacterial infections (e.g., TB, leprosy, Mycobacterium avium complex). Antimycobacterial agents Table: Treatment regimens for mycobacterial infections Bacteria Treatment regimen* Prophylaxis Mycobacterium tuberculosis RIPE: Rifampin (RIF), Isoniazid (isoniazid (isonicotinic acid hydrazine (INH)), Pyrazinamide (PZA), Ethambutol (EMB) 3- to 4-drug regimen (to reduce resistance) Isoniazid […]
Parkinson’s Disease Drugs
Overview Definition Parkinson’s disease (PD) is a degenerative disease of the basal ganglia characterized by a clinical syndrome manifesting with diminished facial expression, bradykinesia, festinating gait (progressively shortened and accelerated steps), cogwheel rigidity, and a “pill-rolling” tremor at rest. Pathophysiology Pharmacotherapy for Parkinson’s disease Levodopa Chemistry and pharmacodynamics Pharmacokinetics Indications Recommended as 1st-line therapy for […]