BIOAVAILABILITY OF RIFAMPICIN, ISONIAZID AND PYRAZINAMIDE FROM FIXED-DOSE COMBINATION CAPSULES

SETTING: The absorption of rifampicin, isoniazid and pyrazinamide was tested after administration of each drug in free combinations and in a fixed-dose combination of the three drugs, known as Trifazid(R). OBJE CTIVE: To examine the relative bioavailability of rifampicin, isoniazi d and pyrazinamide after oral administration of the drugs given alone in comparison to that of the same drugs after administration of Trifaz id(R). DESIGN: An open, randomized, cross-over study comprising 16 hea lthy volunteers. RESULTS: The pattern of absorption, plasma concentrat ions and pharmacokinetic parameters were very similar after administra tion of the drugs in free and fixed combinations. CONCLUSION: The trip le combination of antituberculosis drugs could replace the separate dr ugs in the treatment of tuberculosis.