Doxycycline

C. diff Risk

Low

Oral Bioavailability

Excellent

Approximate Cost

IV: $$$
PO: $

Dosing

Adult

100mg PO BID

Renal

No change required

Pediatric

2mg/kg/dose Q12H
Maximum: 100mg/dose

No adjustment required for renal insufficiency.

General Information

Common Usage

  • ┬áSkin and soft tissue infection

  • Methicillin resistant staphylococcus aureus infections

  • Community acquired pneumonia

  • Malaria prophylaxis

  • Zoonoses

Drug Monitoring

Laboratory

  • Consider periodic LFTs with prolonged use

Clinical

  • Hypersensitivity

  • Diarrhea

  • GI effects

  • Drug interactions

  • Photosensitivity (avoid prolonged sun exposure)

Adverse Effects

  • Photosensitivity

  • Permanent staining of developing teeth (avoid in pregnant women and children <8y)

  • GI effects

  • Rash

Major Interactions

Divalent cations - decreased absorption

Some anticonvulsants can decrease doxycycline levels

Increased digoxin levels

Increased INR with warfarin

Pharmacology

Antimicrobial class: Tetracycline

Pregnancy category: D

Average serum half life: 18 hours

Biliary penetration: Therapeutic

CSF penetration: Poor

Lung penetration: Therapeutic

Urine penetration: Therapeutic