Antimicrobials: Tetracyclines Flashcards
tetracyclines drugs (3)
tetracycline
minocycline
doxycycline
MoA tetracyclines
reversibly binds to 30S subunit on the ribosome, preventing protein synthesis.
are tetracycline bacteriostatic or bacteriocidal?
bacteriostatic
tetracyclines in renal and hepatic impaired patients
avoid tetracycline and minocycline, dose adjust if the drug is necessary
activity of tetracyclines
- good activity against gram pos and gram neg EXCEPT pseudomonas
- no activity against gram neg anaerobes
- very good against atypical pathogens of pneumonia (doxycycline)
- MRSA (doxycycline)
which tetracycline is good for MRSA?
doxycycline - MRSA in cellulitis
one of few PO drugs for MRSA.
distribution of tetracyclines
everywhere
half life of tetracyclines
8 - 16 hours
can dose less freq’ly than PCN
adverse events of tetracycline
hypersensitivity
photosensitivity
depression of skeletal growth in children (tetracycline)
GI symptoms
hepatotoxicity
CNS symptoms
aggravation of pre existing renal failure (tetracycline)
tetracycline patient education (2)
- give a 2-4 hour window between tetracycline and di-, trivalent cations like milk, antacids, sucralfate, didanosine.
- take with a lot of water and do not lay down after as it is a major esophageal irritant
fanconi syndrome
expired tetracycline can cause renal dysfunction
dose adjustment of the tetracyclines
necessary for tetra and mono with decreased renal/hepatic function but doxy does not need to be reduced.
monitoring while on tetracyclines
C&S
CBC
RFTs
pregnancy category/considerations of tetracyclines
D
will go into breast milk
pediatric considerations: tetracyclines
watch for effects on teeth
