Mechanism of action, clinical uses, and adverse effects of beta lactam antibiotics

Pharmacology of Beta Lactam Antibiotics

Beta Lactam Antibiotics

This class of antibiotic agents, including penicillin derivatives, (penams), cephalosporins (cephems), monobactams, and carbapenems, is the most widely used antibiotic. In fact, more than half of the antibiotics that were commercially sold in 2003 were ?-lactam compounds. Beta lactam antibiotics are characterized by a molecular ?-lactam ring structure (Drawz & Bonomo, 2010). The beta lactam antibiotics inhibit the biosynthesis of the cell walls of bacterial organisms by interfering with the synthesis of peptidoglycan. . The penicillin-binding proteins (PBPs) are the bacterial enzymes affected by beta lactam antibiotics, which means that beta lactams do not act against microbes that do not have cell walls containing peptidoglycan, such as chlamydiae, mycoplasmata, rickettsiae, and mycobacteria.

Pharmacotherapeutics

The ?-lactam antibiotics are indicated for the treatment and prevention of bacterial infections. When first introduced to the market, ?-lactam antibiotics were only effective against Gram-positive bacteria (Drawz & Bonomo, 2010). With further development, ?-lactam antibiotics were formulated to act as broad-spectrum antibiotics that are active against Gram-negative organisms (Drawz & Bonomo, 2010).

Pharmacodynamics

The bacteriocidal ?-Lactam antibiotics act by inhibiting the synthesis of the peptidoglycan layer of the bacterial cell wall. The structural integrity of bacterial cell walls is dependent on the peptidoglycan layer. This is particularly true for Gram-positive organism in which the peptidoglycan layer is the primary and outermost component of the cell wall. When ?-Lactam antibiotics are present in the bacterial cell medium while it is dividing, it causes the bacteria to shed cell walls, rendering them unable to divide; instead the bacteria form enlarged and fragile spheroplasts.

Adverse Drug Reactions (ADR)

Common adverse effects of ?-lactam antibiotics include rash, hives (urticarial), diarrhea, nausea, superinfection (particularly of candidiasis). Less frequently, people who are administered ?-lactam antibiotics develop angioedema, dermatitis, erythema, fever, pseudomembranous colitis, vomiting. When ?-lactam antibiotics are administered parenterally, commonly experienced adverse effects are inflammation and pain.

Patient Teaching / / Nursing Interventions

The key considerations in nursing interventions that utilize antibiotics are as follows: 1) Identification of the microbe; 2) Client assessment, including history of drug allergy; 3) Administration of the drug specific to the microbe involved; 4) Safe, accurate, and timely administration of the drug; 5) Evaluation of the drug effects; 6) Monitoring for any adverse reactions; and, 7) Educating the client (Holten & Onusko, 2000). Advice to patients taking antibiotics includes the following: 1) Finish all the prescribed amount of antibiotics; 2) Take all medications at evenly spaced intervals; 3) Take a missed dose as soon as remembered but not at the same time as the next dose; 4) Not share or save medications; 5) Assess for infection and responses, not positive and adverse, to the medication; and, 6) Wear allergy ID to alert health care personal of drug allergies (Holten & Onusko, 2000).