Doxycycline
VIBRAMYCIN
Pronunciation: dox-i-SYE-kleen
“Vibrating Docked cyclone”
What it isTetracycline inhibiting the 30S ribosomal subunit; atypical, tick-borne and skin infections.
Why this oneUsable in renal failure unlike other tetracyclines, and first-line for Rickettsia at any age.
What limits itPhotosensitivity and pill esophagitis — take upright with water. Cations bind it; avoid in pregnancy.
FDA-approved for
- bacterial infections (~1967)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Bacterial infection | Adults | 200 mg day 1 (100 mg q12h) | 100 mg/day | 100 mg q12h (severe/chronic) |
| Bacterial infection | Peds >8 y & <45 kg | 4.4 mg/kg/day divided BID day 1 | 2.2 mg/kg/day | 2.2 mg/kg q12h (severe/life-threatening) |
| Uncomplicated gonorrhea | Adults | 100 mg BID × 7 days | 100 mg BID | 300 mg stat then 300 mg in 1 h (single-visit alt.) |
Renal No excessive accumulation at usual doses in renal impairment (no adjustment)
Hepatic Undefined
Instructions
- Take with adequate fluid to reduce risk of esophageal irritation/ulceration.
- If gastric irritation occurs, may give with food or milk (absorption not markedly affected).
- Streptococcal infections: continue therapy ≥10 days.
- Children ≥45 kg receive the adult dose.
Available strengths
- cap 40, 50, 75, 100, 150 mg
- susp 25 mg/5 mL
- inj 100, 200 mg
- tab 20, 50, 75, 100, 150 mg
- DR tab 50, 60, 75, 100, 150, 200 mg
Cautions
- Photosensitivity
- Permanent tooth discoloration/enamel hypoplasia and reversible bone growth inhibition with use in later pregnancy/childhood
- Superinfection / C. difficile
- Intracranial hypertension
Adverse reactions
- Anorexia
- Nausea
- Vomiting
- Diarrhea
- Glossitis/dysphagia
- Enterocolitis
- Photosensitivity
- Tooth discoloration
Pregnancy Tetracyclines may cause fetal harm (tooth discoloration, inhibition of bone growth) with use in 2nd/3rd trimester
Lactation Undefined
Cost
Generic entryLong generic
NO BOXED WARNINGS
Principal riskEsophagitis if taken without adequate fluid
Classes and tags
Clinical profile
Legacy pregnancy categoryD
Defining liabilityAllergy, gastrointestinal effects and agent-specific renal, hepatic, hematologic or interaction risks.
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