Lincosamides

Question 1

What the MOA of lincosamides?

Answer 1

MOSTLY bacteriostatic, May be bactericidal, Time-dependent.Binds to 50S ribosomal subunit → inhibition of protein synthesis

Question 2

What are the main mechanisms of resistance?

Answer 2

Changes to target site
Mutations
Enzyme modification
Methylases
Enzyme Inactivation
G-ves are intrinsically resistant
Not affected by macrolide efflux pumps

Question 3

What are the pharmacokinetics?

Answer 3

A - Oral absorption = almost complete (≈ 100%). t1/2 = 2.9hrs. Topical = 10%
D - Good penetration into tissues / fluids. Abscess, Phagocytes, macrophages, Neutrophils *Bone (60%) and joints (85%)
M - Liver
E - Liver, Bile, Urine (10% unchanged) t1/2 = 2.9hours = 6 hrs (anuria)

Question 4

What is the spectrum of activity?

Answer 4

MAJOR TARGETS
Gram + Aerobes, Anaerobes, Other: Malaria, Toxoplasma, Pneumocystis

Question 5

Gaps in the spectrum

Answer 5

Enterococci and gram - aerobes

Question 6

What are the clinical uses?

Answer 6

Intra-abdominal and, Pelvic Infections, Aspiration Pneumonia or Lung Abscess, Skin and soft Tissue Infections
Osteomyelitis, Acne, Oral Infections

Question 7

What are the adverse effects?

Answer 7

GIT Effects
Pseudomembranous colitis
C difficile
Clindamycin resistance
Diarrhoea, Nausea/vomiting
Abdominal cramps
Other Effects
Metallic taste
Impaired hepatic function
Hypersensitivity reactions
Blood dyscrasias
May inhibit neuromuscular transmission

Question 8

How do you manage C difficile colitis?

Answer 8

STOP implicating antibiotic
Avoid antimotility drugs
Treat with: Metronidazole
Oral Vancomycin
Fidaxomicin