Doxycycline Dosing Guidelines for Pediatric Patients

Introduction to Dosage

The American Academy of Dermatology recommends doxycycline dosing for children ≥8 years old and weighing <100 pounds at 2 mg/lb (approximately 4.4 mg/kg) divided into two doses on day 1, followed by 1 mg/lb (approximately 2.2 mg/kg) daily as a single dose or divided into two doses on subsequent days; for children ≥8 years old weighing ≥100 pounds, use adult dosing of 200 mg on day 1 (100 mg every 12 hours) followed by 100 mg daily 1, 2

Doxycycline should generally not be used in children <8 years of age unless the benefits clearly outweigh the risks, primarily due to concerns about permanent tooth discoloration and enamel hypoplasia, as recommended by the American Academy of Dermatology 1, 2
For severe infections where doxycycline is necessary in children <8 years old, the dosing is 2-4 mg/kg/day divided into 2 doses (maximum 200-400 mg/day), according to the American Heart Association 3, 4, 5

For children ≥8 years old and weighing <100 pounds, the American Academy of Dermatology recommends dosing at 2 mg/lb divided into 2 doses (approximately 4.4 mg/kg/day) on day 1, and 1 mg/lb as single daily dose or divided into 2 doses (approximately 2.2 mg/kg/day) on subsequent days 1, 2
For children ≥8 years old and weighing ≥100 pounds, the American Academy of Dermatology recommends dosing at 200 mg (100 mg every 12 hours) on day 1, and 100 mg daily on subsequent days 1, 2

For acne vulgaris, the FDA and the American Academy of Dermatology recommend using doxycycline as adjunctive therapy, not as monotherapy 1, 2
For atypical pneumonia (Mycoplasma or Chlamydophila) in children >7 years old, the Infectious Diseases Society of America recommends dosing at 2-4 mg/kg/day in 2 divided doses 5
For Lyme disease in children ≥8 years old, the Infectious Diseases Society of America recommends standard weight-based dosing, though specific duration depends on disease manifestation 6

The American Heart Association recommends that the maximum daily dose should never exceed adult dosing, regardless of the child's weight 3, 4
The American Academy of Dermatology advises avoiding doxycycline monotherapy for bacterial infections; it should be used as part of combination therapy or for specific susceptible organisms 1, 2
The American Academy of Dermatology warns of significant drug interactions, including avoidance of concurrent use with antacids containing aluminum, calcium, or magnesium; iron preparations; bismuth subsalicylate; and caution with hormonal contraceptives in adolescents 1, 2
The American Academy of Dermatology notes that gastrointestinal side effects (nausea, vomiting, esophagitis) are common, and advises taking with adequate fluids and avoiding lying down immediately after administration 1, 2
The American Academy of Dermatology warns of photosensitivity as a significant concern, and counsels patients and families about sun protection during treatment 1, 2
Doxycycline is Pregnancy Category D and is distributed into breast milk, requiring careful risk-benefit assessment in adolescent females, as recommended by the American Academy of Dermatology 1, 2

The Infectious Diseases Society of America recommends 4 mg/kg/day in 2 divided doses (maximum 100 mg per dose) orally or intravenously for tick-borne diseases, such as HGA and Lyme disease, in children, including those under 8 years old 7, 8, 9
Treatment duration for most tick-borne infections is 10 days 7, 8
This dosing has been successfully used in documented cases of children with HGA and Lyme disease 7, 8, 9

For mild tick-borne illness in children under 8 years, rifampin 10 mg/kg twice daily (maximum 300 mg per dose) for 7-10 days can be used 8, 9
Close observation is required to ensure resolution of clinical and laboratory abnormalities when using alternative therapies 8
For community-acquired pneumonia, amoxicillin 90 mg/kg/day in 2 doses can be used for bacterial pneumonia 10
Azithromycin 10 mg/kg day 1, then 5 mg/kg/day days 2-5 can be used for atypical pneumonia 10

The American Academy of Pediatrics and the Infectious Diseases Society of America provide guidelines for the use of doxycycline in children, including those under 8 years old 7, 8, 9
Severe or life-threatening tick-borne diseases, such as Rocky Mountain spotted fever and HGA, are acceptable indications for doxycycline use in children under 8 years 7, 8, 9