NURS 306 Lecture Notes - Lecture 4: Penicillin Binding Proteins, Side Effects Of Penicillin, Beta-Lactam
Document Summary
Drug of choice for a large number of infections. Beta-lactam ring in structure: essential for antibacterial agents allergic reactions are prinicipal effect (a lot of allergies to pcn) Mechanism of action: beta lactam antibiotics disrupt the cell wall integrity, pcn binding proteins. Penicillin penetrates the cell wall and bind to these proteins on the cytoplasmic membrane of the bacteria: bactericidal: Weaken the cell wall causing it to take up water and rupture lethal to bacteria undergoing active growth and division. Peniciilin binding proteins are only present during growth and division: mammalian cells lack a cell wall- penicillin has no direct effect on the host. Mechanism of penicillin resistance: inability of penicillin to reach the target pbps (penicillin binding proteins) inactivation of the penicillins by bacterial enzymes (penicillinase) Pharmacokinetics: oral- unstable in stomach acid, im- different salts absorbed at different rates, iv- only potassium salt. Distributes well- increased penetration in csf, joints and eye in the presence of inflammation.
