Flucytosine, Griseofulvin, and Terbinafine
Classification and Chemistry Classification In addition to the 3 major classes of antifungal agents (azoles, polyenes, and echinocandins), there are several other clinically important antifungals agents. These drugs include: Chemical structures Pharmacodynamics: Mechanisms of Action Flucytosine Flucytosine is a pyrimidine analog that disrupts both DNA and RNA synthesis. Griseofulvin The exact mechanisms of griseofulvin are […]
Echinocandins
Classification Echinocandins are a group of antifungal agents that target the fungal cell wall and are typically used to treat invasive candidiasis in individuals with neutropenia or those who are critically ill. Chemistry and Pharmacodynamics Chemical structure Mechanism of action Echinocandins exert their effects by inhibiting fungal cell wall production by interfering with the synthesis […]
Polyenes
Classification Polyenes are one of the original classes of antifungal medications. There are 2 primary polyenes that are currently used: Chemistry and Pharmacodynamics Chemical structure Nystatin and amphotericin B have very similar chemical structures, including: Mechanism of action Polyenes exert their effects by creating pores in the fungal cell membrane through binding to ergosterol; however, […]
Azoles
Classification Azoles are a group of widely used antifungal medications, which can be classified into 2 subgroups: Chemistry and Pharmacodynamics Chemical structure Mechanism of action Azoles cause deterioration in the fungal cell membrane by inhibiting ergosterol production. Pharmacokinetics Different azoles have variable (and sometimes complex) pharmacokinetics. Absorption Distribution Table: Pharmacokinetics of azoles Drugs Protein binding […]
Carbapenems and Aztreonam
Chemistry and Classification Beta-lactam classification Carbapenems and monobactams are both members of the beta-lactam family of antibiotics. They are all cell-wall synthesis inhibitors. Members of the beta-lactam family include: Penicillins Cephalosporins Carbapenems: Imipenem Doripenem Meropenem Ertapenem Monobactams: Aztreonam Carbapenem structure Carbapenems consist of: A beta-lactam ring: a 4-member ring containing 2 carbons (the α and […]
Fluoroquinolones
Classification and Chemistry Classification Fluoroquinolones are a class of broad-spectrum antibiotics. The common medications in the class include: 1st generation: norfloxacin (no longer clinically used) 2nd generation: Ciprofloxacin (prototypical drug) Ofloxacin 3rd generation: Levofloxacin Moxifloxacin Gemifloxacin 4th generation: delafloxacin Chemical structure Fluoroquinolone structures: Bicyclic core structure (all) Ketone functional group (quinolones) Fluorine atom (fluoroquinolones) Mechanisms […]
Nitroimidazoles
Chemistry and Pharmacodynamics Chemical structure Nitroimidazoles are composed of an imidazole ring and an attached nitro group. Mechanism of action Nitroimidazoles passively diffuse into the microbial cell. Nitroreductases (produced by susceptible organisms) → reduce the nitro group on the molecule and thus activating it Results in the production of: Free radicals Cytotoxic metabolites → interact […]
Acetaminophen
Chemistry and Pharmacodynamics Definition Acetaminophen, also known as paracetamol (N-acetyl-p-aminophenol), is a nonopioid analgesic and antipyretic agent used to treat pain and fever. Chemical structure Mechanism of action Physiologic effects Pharmacokinetics Absorption Distribution Metabolism Excretion Indications Acetaminophen is an equivalent of aspirin and has analgesic and antipyretic effects; however, acetaminophen does not have platelet-inhibiting effects […]
Sulfonamides and Trimethoprim
Classification Sulfonamide antibiotics are antimicrobial drugs containing a sulfonamide functional group. Sulfamethoxazole is the prototypical drug in the class. Other sulfonamide antibiotics include: Sulfadiazine Sulfisoxazole Many other sulfonamide drugs are not antimicrobial: Sulfasalazine (treats Crohn’s disease) Sulfonylureas (antidiabetic agents such as glipizide) Some diuretics (e.g., acetazolamide, chlorthalidone, furosemide, and hydrochlorothiazide) Some antiviral and antiretroviral medications […]
Glycopeptides
Chemistry and Pharmacodynamics Definition Glycopeptide antibiotics (GPAs) are actinomycete-derived, glycosylated, nonribosomal peptides, which target gram-positive bacteria by inhibition of cell wall synthesis: Vancomycin Teicoplanin (not available in the United States) Chemical structure Both vancomycin and teicoplanin are heptapeptides, but the carbohydrate groups of each drug differ. Mechanism of action Glycopeptides are bactericidal through inhibition of […]