Ethambutol Safety in Children with Tuberculosis

Introduction to Ethambutol Use

Ethambutol can be safely used in small children with tuberculosis, including those under 5 years of age, when there is concern about drug resistance, though it should be used with caution in children whose visual acuity cannot be monitored 1, 2
The Centers for Disease Control and Prevention, as reported in MMWR Recommendations and Reports, recommends ethambutol as a first-line drug for treating all forms of tuberculosis to prevent emergence of rifampicin resistance when primary isoniazid resistance may be present 1

The British Thoracic Society guidelines state that ethambutol can be used in younger children without undue fear of side effects 3
For children aged five years or more, ethambutol can be recommended at a dosage of 15 mg/kg/day without taking any more precautions than for adults 3

The Centers for Disease Control and Prevention recommends a dosage of 15-20 mg/kg/day (maximum 2.5g) for children 2

The primary concern with EMB use is retrobulbar neuritis, which can manifest as decreased visual acuity or decreased red-green color discrimination 2
The risk of ocular toxicity is dose-related, with minimal risk at a daily dose of 15 mg/kg 2, 4

The British Thoracic Society recommends baseline visual acuity testing should be performed when possible before starting EMB 5
For children old enough to cooperate, visual acuity should be tested by Snellen chart before EMB is prescribed 5
Parents or caregivers should be informed about potential visual symptoms and instructed to stop the medication immediately if such symptoms occur 5
If any deterioration in visual fields or color vision is detected, strong consideration should be given to stopping or switching the EMB 6

The British Thoracic Society guidelines state that in TB meningitis, EMB can be used as the fourth drug in the initial treatment phase, along with rifampicin, isoniazid, and pyrazinamide 3

The CDC/ATS/IDSA guidelines recommend 15-20 mg/kg/day as a single daily dose for children, which represents the cornerstone dosing strategy 7
Children weighing more than 40 kg should be dosed as adults using weight-based tables 7

For twice-weekly directly observed therapy (DOT), the recommended dose is 50 mg/kg (maximum 2.5 g) 7
These intermittent regimens are particularly useful for ensuring adherence through directly observed therapy 7

Ethambutol can be safely used in children under 5 years of age at 15 mg/kg/day when there is suspected or proven resistance to isoniazid or rifampin 8

Monthly visual monitoring is mandatory for all children on ethambutol, with specific approaches based on age 7