Beta lactams - Penicillin

Question 1

MOA

Answer 1

inhibits cell wall synthesis

Question 2

Use indications

Answer 2

Targets gram +ve, particularly anaerobes
Can work against some gram -ve bacteria: fusobacterium, pasturella
Urinary tract infections

Question 3

Side effects/contraindications

Answer 3

It is very safe, side effects usually due to symbiosis - don’t give horses/small herbivores PO

• hypersensitivities (allergic reactions)
• doesnt cross BBB, eye globe, prostate

Question 4

PK quirks

Answer 4

B-lactams only kill during bacteria replication
hydrophilic
rapid absorption
weak acid
renal elimination - concentrates in urine
Free procaine may elicit a CNS reaction

Question 5

Representative drugs

Answer 5

Penicillin G is often combines with procaine or benzathine –> combines with salts to increase half life

Staohylococcus often have B-lactamses but there are B-lactamase resistant penicillins
eg amoxicillin-clavulonic acid (which is effective against G-ve E.coli and proteus)

Ticarcillin - clavulonic kills pseudomas

Question 6

-cidal vs -static

concentration/time

Answer 6

bactericidal, time dependant