MedDataToolMedDataTool

Doxycycline

Rx only
Tetracycline✓ FDA-verified
View full FDA label ↗
Doxycycline is an antibiotic used to treat various infections, including certain types of fevers, respiratory infections, and sexually transmitted infections. It works by stopping bacteria from making proteins they need to grow and multiply. You typically start with a dose of 200 mg on the first day, taken as 100 mg every 12 hours, followed by a maintenance dose of 100 mg once a day. It's important to know that doxycycline can cause permanent discoloration of teeth in children under 8, so it should only be used in severe cases for this age group. Additionally, you should avoid taking doxycycline with isotretinoin, as this combination can increase the risk of serious side effects.
✦

Uses

  • Rocky Mountain spotted fever.
  • Typhus fever.
  • Q fever.
  • Rickettsialpox.
  • Tick fevers caused by Rickettsiae.
  • Respiratory tract infections from Mycoplasma pneumoniae.
  • Lymphogranuloma venereum from Chlamydia trachomatis.
  • Psittacosis from Chlamydophila psittaci.
  • Trachoma from Chlamydia trachomatis.
  • Inclusion conjunctivitis from Chlamydia trachomatis.
  • Uncomplicated urethral, endocervical, or rectal infections from Chlamydia trachomatis.
  • Nongonococcal urethritis from Ureaplasma urealyticum.
  • Relapsing fever from Borrelia recurrentis.
  • Chancroid from Haemophilus ducreyi.
  • Plague from Yersinia pestis.
  • Tularemia from Francisella tularensis.
  • Cholera from Vibrio cholerae.
  • Campylobacter fetus infections from Campylobacter fetus.
  • Brucellosis from Brucella species.
  • Bartonellosis from Bartonella bacilliformis.
  • Granuloma inguinale from Klebsiella granulomatis.
  • Upper respiratory infections from Streptococcus pneumoniae.
  • Anthrax from Bacillus anthracis.
  • Uncomplicated gonorrhea from Neisseria gonorrhoeae.
  • Syphilis from Treponema pallidum.
  • Yaws from Treponema pallidum subspecies pertenue.
  • Listeriosis from Listeria monocytogenes.
  • Vincent's infection from Fusobacterium fusiforme.
  • Actinomycosis from Actinomyces israelii.
  • Infections from Clostridium species.
  • Acute intestinal amebiasis as an adjunct to amebicides.
  • Severe acne as adjunctive therapy.
  • Prophylaxis of malaria from Plasmodium falciparum.
◷

Dosage

  • 200 mg on the first day, then 100 mg daily for adults. 100 mg every 12 hours for severe infections in adults. 2.2 mg/kg every 12 hours for pediatric patients under 45 kg. 4.4 mg/kg on the first day, then 2.2 mg/kg daily for pediatric patients over 8 years. 100 mg twice daily for uncomplicated gonorrhea in adults for 7 days. 100 mg twice daily for uncomplicated urethral infections in adults for 7 days. 100 mg twice daily for early syphilis for 2 weeks. 100 mg twice daily for syphilis over one year for 4 weeks. 100 mg twice daily for acute epididymo-orchitis for at least 10 days. 100 mg daily for malaria prophylaxis in adults.
  • Always follow your doctor's specific instructions for your dose.
⚠

Side effects

Common

NauseaVomitingDiarrheaGlossitisSkin rashesIntracranial hypertensionEsophageal ulcerationsHypersensitivity reactions

Serious

Severe skin reactions like Stevens-Johnson syndromeHepatotoxicity
🛑

Warnings

⚠ Important warnings

  • May cause permanent tooth discoloration in children under 8 years.
  • Use only if benefits outweigh risks in severe conditions for children under 8.
  • Risk of Clostridium difficile associated diarrhea.
  • Severe skin reactions can occur.
  • Intracranial hypertension risk in overweight women.
  • Avoid use with isotretinoin.
  • May increase blood urea nitrogen levels.
  • Photosensitivity can occur with sun exposure.
⇄

Drug interactions

  • Anticoagulantsmay require dosage adjustmentCaution
  • Penicillinmay interfere with its actionCaution
  • Antacidsreduces absorption of doxycyclineCaution
  • Bismuth subsalicylatereduces absorption of doxycyclineCaution
  • Barbituratesdecrease doxycycline half-lifeCaution
  • Phenytoindecrease doxycycline half-lifeCaution

Ask about this drug

Answers pulled from the FDA label only.

AI
Other Brands:
Medical Disclaimer: This content is provided for informational and educational purposes only and is not intended as medical advice. Always consult a qualified healthcare provider before taking any medication.
Data Source: Publicly available drug labeling information from the U.S. Food and Drug Administration (FDA).