C/16. Clindamycin. Streptogramins. Oxazolidinones

Question 1

Drugs need to know in this topic

Answer 1

Clindamycin
Quinupristin/dalfopristin
Linezolid

Question 2

Clindamycin

Answer 2

Mechanism is similar to macrolide

Narrow specturm
Gram positive, anaerobic flora
Skin and sofr tisse infection caused by staph, and strep
Community acquried MRSA
Osteomyelitis by staph
Endocarditis prophylaxis
Pneumocystis jirovecii, toxoplasmosis
B.fragilis infection

Oral, parenteral
Hepatic metabolism
Excreted in bile and urine

Resistant mechanism
Methylation of ribosomal binding site
Enzymatic inactivation

GI symptoms
Skin rash
Neutropenia
Hepatotoxicity
C. Difficile superinfection

Question 3

Quinupristin/Dalfopristin

Answer 3

Streptogramin
Binds to the 50S ribosomal subunit; blocking the exit channel on the ribosome
Bactericidal effect

Effective against MRSA. PRSP, VRSA, and resistant strains of E. Faecium

IV administraion
Inhibitor of CYP450 enzymes

Resistant mechanism
Efflux pump
E. Faecalis is resistant

Arthralgia-myalgia syndrome

Question 4

Linezolid

Answer 4

Oxazolidinone
Binds to the 50S ribosomal subunit; inhibits the formation of initiation complex in bacterial translation
Bacteriostatic effect

Effective against multidrug resistant gram-positive cocci

Oral/parenteral
Hepatic metabolism
Inhibitor of MAO-A and MAO-B

Thrombocytopenia
Neutropenia
Optic neuropathy
Serotonin syndrome