Question | Answer |
Tetracycline MoA | Bind to the 30S ribosomal subunit, reversibly inhibiting the binding of aminoacyl-tRNA (no protein synth, no cell wall)
Mainly Static |
Tetracycline ADRs | Erosive/sclerosing
Renal fail @ expirn
Teeth staining; bone growth impaired; teratogenic
Photosenstivity (highest w/ democlocycline)
Hepatotoxicity (w/ high dose in renal failure)
NVD
anti-anabolic: raise BUN, acidosis, hyperphosphatemia |
Minocycline ADRs | Vertigo (more in women)
Skin & mucous membrane pigmentation
Lupus-like symptoms |
TCN DDIs | Anticonvulsants (Carbamazepine, Phenytoin, Phenobarbital) decrease [TCN]
Antagonistic w/ PCNs (static, while PCNs are cidal)
Lowers efficacy of OCs!
Complex w/ Fe, Zn, Ca, Mg, Al, bismuth, binding resins
Isotretinoin causes benign cranial hype |
TCN on food/empty stomach? | Tetracycline on empty stomach
Doxy & Minocycline w/ food |
TCN IV or PO? | PO: TCN, Doxycycline, Minocycline
IV: Doxy, Mino, Tigecycline |
Doxycycline | DON'T inject IM! It will burn tissue to death
Don't dose adjust in renal dysfunction |
Tetracycline PK | TCNs distribute to all tissues, liver, bile, prostate, urine, CSF, Synovial |
Tigecycline (Tigacil) | distributes best to GI organs. Indicated for IA infections. Can Tx DR enterococcus. Also for cSSIs.
Don't give in pneumonia; increases mortality!
Requires dose adjustment in hepatic impairment
Elevates LFTs
NV (slow rate to fix), AAD |
Drugs for IA infections | Tigecycline, cefoxitan and cefotetan, moxiflox, iminem, erbipenem. Zosyn & Unasyn too, but freq dosing is inconvenient |
Tetracycline SoA (all TCNs except Tigecycline) | They treat rare/WEIRD organisms. 2nd line for atypicals (after 1st line Quinolones) along with macrolides
broad spectrum of aerobic and anaerobic bacteria including intracellular pathogens
G- & G+
We don't use very often though b/c of ADRs |
Demeclocycline | for Tx of SIADH only!
Causes hyponatremia, fluid overload, concentrated urine. |
General Use for TCNs | CAP
Non-gonococcal UTI (chlamydia trachomatis)
PID - IV doxycycline w/ cefoxitin or cefotetan
Atypical pneumonia/bronchitis: Chlamydia pneum, C. psittaci, Mycoplasma pneu, Legionella
Lyme disease
Rickettsia
H. pylori (TCN w/ other drug |
Which drugs should NOT be used in babies? | TCNs & Quinolones |