Isoniazid with rifampicin is a medicine used to treat and prevent tuberculosis and may be associated with other medicines.
This remedy is available in pharmacies but can only be obtained by prescription and should be used with caution because of the contraindications and side effects it presents.
How to use
In all forms of pulmonary and extrapulmonary tuberculosis, except for meningitis and patients weighing more than 20 kg, the doses shown in the following table should be taken per day:
| Weight | Isoniazid | Rifampicin | Capsules |
| 21 - 35 Kg | 200 mg | 300 mg | 1 200+ 300 capsule |
| 36 - 45 Kg | 300 mg | 450 mg | 1 capsule of 200 + 300 and another of 100 + 150 |
| More than 45 kg | 400 mg | 600 mg | 2 200 + 300 capsules |
The dose should be administered in a single dose, preferably in the morning on an empty stomach, or two hours after the meal. Treatment should be performed for 6 months, however the doctor may change the dosage.
Mechanism of action
Isoniazid and rifampicin are substances that fight the bacterium that causes tuberculosis, known as Mycobacterium tuberculosis .
Isoniazid is a substance that inhibits rapid division and leads to the death of tuberculosis-causing mycobacteria, and rifampicin is an antibiotic that inhibits the multiplication of sensitive bacteria and although it has action against various bacteria, it is especially used in the treatment of leprosy and of tuberculosis.
Who should not use
This medicine should not be used in people with an allergy to any component of the formula, people with liver or kidney problems, or people taking medicines that may induce liver changes.
In addition, it is not recommended for use in children weighing less than 20 kg body weight, pregnant or breastfeeding women.
Possible side effects
The most common side effects that can occur with the use of this medication are loss of sensitivity of the extremities like feet and hands and changes in the liver, especially in people over 35 years. Neuropathy, usually reversible, is more common in malnourished people, alcoholics, or people who already have liver problems and are exposed to high doses of isoniazid.
In addition, due to the presence of rifampicin, there may also be loss of appetite, nausea, vomiting, diarrhea and intestinal inflammation.
