3. Antibiotics - Clindamycin Flashcards
What class of drug is clindamycin?
lincosamide
What is the history of lincosamides?
- first came Lincomycin, first isolated from Streptomyces lincolnesis
- now replaced by clindamycin which is a semisynthetic derivative synthesised in 1968
What is the spectrum of activity of clindamycin (what does clindamycin work against)?
- gram +ve/gram -ve bacteria
- anaerobic/facultative/aerobic
- penicillinase producing staph.
- bacteroides
- prevotella
- porphyromonas, veillonella, peptostrep, actinomyces, eubacteria and clostridium
What tends to be resistant to clindamycin?
aerobic gram -ve bacilli
What is the mechanism of action of clindamycin?
inhibits protein synthesis
- binds to the 50S ribosomal subunit
bacteriostatic, bactericidal at higher concentrations
What does clindamycin have the same site/mechanism of action as?
macrolides:
- clarithromycin
- erythromycin
What is the oral absorption % of clindamycin?
90%
What is the half life of clindamycin?
3 hours
What is the peak serum level of clindamycin?
2.5ugmL
What is the peak serum time of clindamycin?
45-60 mins
Does food affect clindamycin?
no
What is the distribution of clindamycin?
wide, PMNs
What does clindamycin penetrate?
- penetrates bone very well
- does not penetrate the CSF
Where is clindamycin metabolised?
liver (90%)
Where is clindamycin concentrated?
polymorphonuclear leukocytes, alveolar macrophages and abscess tissue
How is clindamycin excreted?
urine
What preparations can clindamycin come in?
- IM
- slow IV infusion
- oral capsules
- paediatric suspension
What are the main unwanted effects of clindamycin?
- Nausea/vomiting
- Abdominal pain
- Oesophagitis
- Glossitis
- Stomatitis
- Allergy
- Myelosupression (reversible)
- Metallic taste
- Maculopapular rash (3-10%)
What is a serious and potentially fatal unwanted effect of clindamycin?
pseudomembranous colitis (possibly 10%)
What kinds of patients are more at risk of pseudomembranous colitis?
- had recent antibiotics
- middle aged - elderly
- women
- following surgery
- GI disturbance
What other antiobiotic notably can also cause pseudomembranous colitis?
amoxicillin
What antiobiotics would you give if the pt has pseudomembranous colitis?
vancomycin or metronidazole
What are the symptoms of pseudomembranous colitis?
GI upset, diarrhoea, abdominal cramps (mild to severe)
- bloody stools
- fever
- urge to have a bowel movement
- watery diarrhoea (often 5-10 times per day)
What interacts with clindamycin?
- non-depolarising neuromuscular blocking agents (theoretical)
- absorption slowed by some anti-diarrhoeal drugs
- antagonism with erythromycin
What are the contraindications of clindamycin?
- allergy
- avoid 2 months following pseudomembranous colitis
What are the indications for clindamycin?
second-line antibiotic
- as for penicillin for oro-facial infections
- penicillin allergy
- refractory to penicillin(s)/metronidazole
- beta lactam resistance
What does the BNF/SDCEP state regarding the use of clindamycin?
- Clindamycin should not be used routinely
- No more effective than Penicillin
- Cross resistance with erythromycin-resistant bacteria
What is the dose of clindamycin?
150-300mg
What is the interval for taking clindamycin?
6 hourly
What is the duration of taking clindamycin?
3-5 days
What is the route of clindamycin delivery?
oral
Does clindamycin require a loading dose?
no
When would clindamycin use be immediately ceased?
diarrhoea
Summary slide (clindamycin):
