Pharmacology: Penicillin Mechanism of Action and Classification

Study Notes

Mechanism of Action: Penicillin works by inhibiting the synthesis of the bacterial cell wall, specifically by blocking the cross-linking of peptidoglycan chains.
Classification: Penicillin is a type of beta-lactam antibiotic, which is a class of antibiotics that includes cephalosporins, carbapenems, and monobactams.
Types: There are several types of penicillin, including:
- Natural penicillins (e.g. penicillin G)
- Semisynthetic penicillins (e.g. ampicillin, amoxicillin)
- Synthetic penicillins (e.g. piperacillin)

Spectrum of Activity: Penicillin is effective against a wide range of bacterial infections, including:
- Gram-positive bacteria (e.g. Staphylococcus, Streptococcus)
- Some Gram-negative bacteria (e.g. Neisseria, Haemophilus)
Indications: Penicillin is used to treat various infections, including:
- Pneumonia
- Meningitis
- Skin and soft tissue infections
- Bone and joint infections
- Endocarditis
Resistance: Bacterial resistance to penicillin has become a significant concern, with many bacteria producing beta-lactamases that can break down the antibiotic.

Penicillin's mechanism of action involves inhibiting bacterial cell wall synthesis by blocking peptidoglycan chain cross-linking.
Penicillin is classified as a beta-lactam antibiotic, a class that also includes cephalosporins, carbapenems, and monobactams.

Penicillin is effective against a wide range of bacterial infections, including Gram-positive bacteria like Staphylococcus and Streptococcus.
Penicillin is also effective against some Gram-negative bacteria, such as Neisseria and Haemophilus.