Antimicrobials
Doxycycline

Doxycycline

Low
Excellent (90 to 100%)
See Additional Information

Spectrum of Activity

Dosing

General Information

  • GI upset
  • Erosive esophagitis
  • Photosensitivity rash
  • Teeth staining
  • Vulvovaginal candidiasis

Antacids: May decrease the absorption of Tetracyclines

  • Management: Separate administration of antacids and oral tetracycline derivatives by several hours when possible to minimize the extent of this potential interaction

Bismuth Subcitrate: May decrease the serum concentration of Tetracyclines

  • Management: Avoid administration of oral tetracyclines within 30 minutes of bismuth subcitrate administration. This is of questionable significance for at least some regimens intended to treat H. pylori infections

Bismuth Subsalicylate: May decrease the serum concentration of Tetracyclines

  • Management: Consider dosing tetracyclines 2 hours before or 6 hours after bismuth. The need to separate doses during Helicobacter pylori eradication regimens is questionable

Divalent and Polyvalent Cations (Calcium, Magnesium, Zinc, Iron): May decrease the absorption of tetracyclines. Of concern only with oral administration of both agents

  • Management: Consider administering the oral cation at least 2 hours before or 4 hours after the dose of tetracycline

CarBAMazepine: May decrease the serum concentration of Doxycycline

  • Management: Consider increasing the doxycycline dose, or using another tetracycline derivative due to the potential for reduced doxycycline therapeutic effects when coadministered wth carbamazepine

Iron Preparations: Tetracyclines may decrease the absorption of Iron Preparations. Iron Preparations may decrease the serum concentration of Tetracyclines

  • Management: Avoid this combination if possible. Administer oral iron preparations at least 2 hours before, or 4 hours after, the dose of the oral tetracycline derivative

Sucralfate: May decrease the absorption of Tetracyclines

  • Management: Administer most tetracycline derivatives at least 2 hours prior to sucralfate in order to minimize the impact of this interaction

Vibramycin

  • Absorption: Oral: Almost completely absorbed from the GI tract. Peak plasma concentration may be reduced ~20% by high-fat meal or milk
  • Distribution: Widely into body tissues and fluids including synovial, pleural, prostatic, seminal fluids, and bronchial secretions; saliva, aqueous humor, and CSF penetration is poor
  • Protein binding: >90%
  • Metabolism: Not hepatic; partially inactivated in GI tract by chelate formation
  • Bioavailability: Reduced at high pH; may be clinically significant in patients with gastrectomy, gastric bypass surgery or who are otherwise deemed achlorhydric
  • Half-life elimination: 18-22 hrs
  • Excretion: Feces (30%); urine (23% to 40%)
  • Cost:
    • PO: $ (<$25/day)
    • IV: $$ ($26-$100/day)
  • Currently on formulary
  • Formulations:
    • 100 mg tablet
    • 50 mg capsule
    • 5 mg/mL oral liquid