RIFAFOUR®e-275 TABLETS

SCHEDULING STATUS:
S4

PROPRIETARY NAME
(and dosage form):

RIFAFOUR®e-275 TABLETS

COMPOSITION:
Each tablet contains:
Rifampicin 150 mg
Isoniazid 75 mg
Pyrazinamide 400 mg
Ethambutol 275 mg
Contains sodium ascorbate as anti-oxidant.

PHARMACOLOGICAL CLASSIFICATION:
A 20.2.3 Tuberculostatic combinations

PHARMACOLOGICAL ACTION:
Rifafour e-275 tablets is a combination of four first line agents used in the treatment of tuberculosis. Rifampicin is a semi-synthetic, broad-spectrum bactericidal antibiotic. Isoniazid is a synthetic, antitubercular agent which is bacteriostatic against semi-dormant bacilli and bactericidal against actively dividing mycobacteria. Pyrazinamide may be bactericidal or bacteriostatic, depending on its concentration and the susceptibility of the organism. Ethambutol is a synthetic, bacteriostatic antitubercular agent. All agents are readily absorbed following oral administration, with wide distribution to most tissues and fluids including cerebrospinal fluid.

INDICATIONS:
Initial phase treatment of pulmonary and extrapulmonary tuberculosis in new adult patients and re-treatment of adult cases.

CONTRA-INDICATIONS:
Rifafour e-275 tablets are contra-indicated in:
• patients with hypersensitivity to rifamycins, isoniazid, pyrazinamide, ethambutol or other chemically related medication.
• the presence of jaundice or active hepatic disease.
• patients with optic neuritis.
Safety in pregnancy has not been established.
All agents of Rifafour e-275 tablets are excreted in breast milk. Safety during lactation has not beer established. Rifafour e-275 should not be used in children under 13 years of age.

WARNINGS:
Liver function should be checked before and during treatment and special care should be exercised in alcoholic patients, the elderly or those with pre-existing liver disease.
Caution should be observed with the use of Rifafour e-275 tablets in the following patients:
• Impaired kidney function: dosage adjustment may be required according to the serum concentration of ethambutol
• Patients with visual defects: should visual disturbances occur during treatment these must be reported immediately and the medicine discontinued pending visual eva luation
• Patients at risk of neuropathy or pyridoxine deficiency, including those who are diabetic, alcoholic, malnourished, uraemic or pregnant: pyridoxine supplementation (in a 10 mg to 50 mg daily dose) is usually required in these instances
• Patients with a history of gout
• Patients with porphyria
• Patients with epilepsy, as convulsions may be precipitated
• Patients with a history of psychosis
• Patients with diabetes: pyrazinamide may cause interference with urine ketone determinations
• Rifampicin may decrease the effect of oral contraceptives and patients are advised to change to non-hormonal methods of birth control
• Treatment with Rifafour e-275 tablets may produce reddish colouration of urine, tears and saliva. Contact lenses may be irreversibly stained.

DOSAGE AND DIRECTIONS FOR USE:
Take Rifafour e-275 tablets with a full glass of water 1 hour before, or 2 hours after a meal. However, if gastrointestinal irritation occurs, the tablets may be taken with food. If aluminium-conta