Clindamycin Flashcards
Clindamycin is a
lincosamide antibiotic; chlorine-substituted derivative of lincomycin
Clindamycin is bactericidal/bacteriostatic
bacteriostatic
Clindamycin MOA
inhibits protein synthesis by binding reversibly to 50S ribosomal subunits of susceptible bacteria
inhibits peptide formation and interferes with translocations step
binds near site where macrolides bind
Clindamycin spectrum coverage
dark purple: prevotella
light purple: streptococcus, s. pneumoniae, viridans, MSSA, MRSA
dark red: fusobacterium
light red: bacteroides, clostridium
Other: pneumocystic jirovecii, protozoa
Clindamycin resistance mechanisms
mutation of bacterial ribosomal RNA
alterations in 50S ribosomal proteins at receptor site
enzymatic inactivation
modification of 23S ribosomal unit of 50S receptor by methylation of adenine (erm)
inducible resistance occurs during therapy
Macrolide and Lincosamide resistance
methylation of the ribosomal target which leads to cross-resistance to macrolides, lincosamides, and streptogramin B
MLSB phenotype which can be constitutive or inducible
Macrolide and Lincosamide resistance is mediated by
plasmids
Efflux by ERY
msrA (low level)
ribosome alteration (ERY, CLI)
Erm (high level)
Drug inactivation (CLI)
inuA (rare)
D-test positive is when
erythromycin causes clindamycin ring to look like a D
msrA
ERY:
CLI:
E: R
C: S
erm
ERY:
CLI:
E: R
C: S inducible
erm
ERY:
CLI:
E: R
C: R constitutive
both negative
ERY:
CLI:
E: S
C: S
Clindamycin absorption
nearly completely absorbed after oral administrayion
Clindamycin can be given
IV/IM or PO
Clindamycin tissue penetration
readily distributed into most fluids and tissues EXCEPT CSF
penetrates well into abbesses and phagocytic cells
high levels in bones
crosses placenta
Clindamycin elimination
metabolized by liver so accumulation may occur in severe hepatic failure, may require dose adjustment
Antimicrobial activity persists in feces for
> 5 days after IV is stopped
Clindamycin 1/2 life
2.5 hours, short
Clindamycin should/should not be renally adjusted
should not
In severe hepatic disease, monitor
liver enzymes during therapy
Clindamycin indications
skin and soft tissue infections caused by strep and staph
- CA MRSA
- inhibits bacterial toxin synthesis (role in necrotizing infections)
respiratory tract infections
other anaerobic infections
- female genital tract
- prophylaxis of endocarditis in patients with valvular disease undergoing certain dental procedures
with primaquine used as alternative for pneumocystis jirovecci pneumonia
with pyrimethamine for AIDS related toxoplasma encephalitis
topical clindamycin for acne and bacterial vaginosis
anaerobic infections (tooth abscesses)
surgical prophylaxis
antibiotic prophylaxis for GBS in penicillin allergic
Clindamycin adverse effects
GI: nausea, vomiting, diarrhea, mostly with PO
skin rash
impaired liver function
neutropenia
C. diff infections
may potentiate effect of neuromuscular blockers if administer concurrently
Clindamycin drug interactions
may block neuromuscular transmission and enhance the action of other blocking agents
Clindamycin use during pregnancy
inconclusive or inadequate evidence in pregnant, WHO recommends avoiding while breast feeding
