Drug

Adults

Children

Common combinations

Possible adverse effects

Daily dose (mg/kg)

Daily dose (mg/kg)

{RHZE}

(mg)

{RH}

(mg)

{RHE}

(mg)

Isoniazide (H)

5 (4 - 6)

10 (10 - 15)

75

75

75

Peripheral neuropathy, liver dysfunction, optic neuritis, toxic psychosis, general convulsions, and rarely symptomatic hepatitis anemia, lupus-like syndrome, or arthralgias

Individuals at risk of peripheral neuropathy, should additionally receive pyridoxine, 10 mg daily.

Rifampicine (R)

10 (8 - 12)

15 (10 - 20)

150

150

150

Gastrointestinal reactions and pruritus with or without rash; but fever, influenza-like syndrome and thrombocytopenia can also appear.

Pyrazinamide (Z)

25 (20 - 30)

35 (30 - 40)

400

-

-

Gastrointestinal intolerance.

Ethambutol (E)

20 (15 - 25)

20 (15 - 25)

275

-

275

Used only in adults because it can cause optic neuritis leading to impairment of visual acuity and color vision, blindness, but also ocular toxicity.

Streptomycin (S)

15 (12 - 18)

15 (12 - 18)

-

-

-

Skin rash, cutaneous hypersensitivity reactions, vestibular and auditory dysfunction.