Lincosamide

Clindamycin

A lincosamide for anaerobic, skin, bone and joint infections, also used on the skin or in the vagina for acne and bacterial vaginosis.

Drug card

Class: Lincosamide
How it works: Binding the 50S subunit so unfinished peptide chains drop off the ribosome
Used for: Serious anaerobic infections
Skin and soft tissue infections
Bone and joint infections
Pneumonia, lung abscess and empyema
Known for: C. difficile colitis (pseudomembranous colitis)
Its name: -mycin means an antibiotic from Streptomyces bacteria

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Mechanism of action

How does clindamycin work?

Clindamycin is made from lincomycin by swapping a hydroxyl group for a chlorine atom. It binds the 23S rRNA of the 50S subunit and mainly stops bacteria growing. It covers staphylococci, streptococci and anaerobes such as Clostridium perfringens, Fusobacterium and Prevotella, but not Enterococcus faecalis, and it does not enter the cerebrospinal fluid in useful amounts.

Uses

What is clindamycin used for?

Serious anaerobic infections
Skin and soft tissue infections
Bone and joint infections
Pneumonia, lung abscess and empyema
Bacterial vaginosis (vaginal cream or gel)
Acne (gel, lotion or solution on the skin)

Side effects

Side effects of clindamycin

C. difficile colitis (pseudomembranous colitis)Known forSerious
Diarrhea
Nausea and vomiting
Abdominal pain
Measles-like rash, the most common reaction
Severe skin reactions (SJS, TEN, DRESS, AGEP)Serious
AnaphylaxisSerious
Jaundice and abnormal liver testsSerious
Acute kidney injurySerious
Esophagitis and esophageal ulcers (capsules)
Unpleasant or metallic taste
Vaginal thrush (vulvovaginal candidiasis)

Known for marks what an exam expects you to know it for.

Watch for

Cautions and what sets it apart

Diarrhea, even weeks after the course, can mean C. difficile colitis: stop clindamycin and test.
Never give it as a rapid IV bolus: fast injection has caused low blood pressure and cardiac arrest.
Capsules taken lying down or with little water can cause esophagitis and esophageal ulcers.
It is not used for meningitis, and it can enhance neuromuscular blockers given during anesthesia.

Good to know: Macrolide-resistant staphylococci and streptococci can carry inducible clindamycin resistance, so labs screen them with a D-zone test. WHO lists it as first choice for necrotizing fasciitis.

Remember it

A way to remember it

Lincosamides: anaerobes out, C. difficile in.

They act on many anaerobes and Gram-positive cocci, but by clearing normal gut bacteria they let C. difficile overgrow, which is why their labels carry a boxed warning for colitis.

Written for biofideX

Its name

-mycin means antibiotic from Streptomyces bacteria
Spans classes: macrolides (azithromycin), lincosamides (clindamycin), glycopeptides (vancomycin), aminoglycosides (streptomycin) and anticancer bleomycin. Gentamicin is spelled -micin.
Every drug name stem

Its class

Lincosamides

Lincosamides bind the 23S rRNA of the 50S ribosomal subunit and stop peptidyl-tRNA shifting from the ribosome's A site to its P site, so it falls away and unfinished proteins are released. They are mainly bacteriostatic and act on Gram-positive cocci and many anaerobes. Their binding site overlaps that of macrolides, so a change in the 23S rRNA can make bacteria resistant to both.

Easily mixed up with macrolides and nitroimidazoles.

Sources

Checked against

Written for biofideX in plain words, after checking these references:

For learning pharmacology, not for treatment decisions: no doses are given, and a prescriber, pharmacist or the product's own label is the word on any one patient. Spotted a mistake? Tell us and we'll correct it.

Practice it

Antibiotics: protein synthesis

Clindamycin is one of 10 drugs practiced together here: their classes, how they work, what they treat and what they're known for.

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