Tetracyclines

Question 1

Tetracycline drugs

Answer 1

Tetracycline, Doxycycline, Minocycline

Question 2

Pharmacokinetics

Answer 2

Oral bioavailability reduced if taken with diary, antacids, Fe supplements (binds divalent and trivalent cations

Question 3

Mechanism

Answer 3

Binds 30s subunit; prevents new aa’s from being added (competitive inhibition of tRNA)
Bacteriostatic

Question 4

Resistance

Answer 4

Tet A protein

resistant to 1 tetracycline = resistant to all tetracyclines

Question 5

Adverse effects

Answer 5

Epigastric distress, calcified tissues (discoloration of tissues, stunt growth temporary)
Nephro- and photo- toxicity

Question 6

Contraindications

Answer 6

Children <8, pregnant or nursing women

Question 7

Clinical uses

Answer 7

Rickettsiae, spirochetes, mycoplasms, chlamydiae
**Rocky mt spotted fever (Rickettsia), Lyme disease (Borrelia), relapsing fever (Borrelia)
**Doxy = genital C. trachomatis
M. pneumoniae (macrolide alternative)
Acne vulgaris, cholera