Doxycycline

C. diff Risk

Low

Oral Bioavailability

Excellent

Approximate Cost

Dosing

100 mg PO/IV every 12 hr

General Information

Unacceptable Uses

Avoid in pregnant women and children < 8 yr, permanent staining of developing teeth may occur.

Common Usage

  • Skin and soft tissue infection

  • Community acquired pneumonia

  • Malaria prophylaxis

  • Zoonoses

  • Methicillin resistant staphylococcus aureus infections

Drug Monitoring

Lab

  • Consider periodic LFTs with prolonged use

Clinical

  • Hypersenistivity

  • GI effects/diahhrea

  • Photosensitivity

Adverse Effects

  • GI upset and erosive esophagitis

  • Photosensitivity rash

  • Teeth staining (avoid in pregnant women and children)

Major Interactions

  • Divalent cations - decreased absorption

  • Increased digoxin levels

  • Increased INR with warfarin

  • Some anticonvulsants can decrease doxycycline levels

Pharmacology

Antimicrobial class: Tetracycline

Pregnancy category: D

Average serum half life: 18 hours

Urine penetration: Therapeutic

CSF penetration: Poor

Biliary penetration: Therapeutic

Lung penetration: Therapeutic