Pyrazinamide Tablets

This product has a good antibacterial effect on human tuberculosis. At pH 5-5.5, the bactericidal effect is the strongest. It is currently the best bactericidal drug for tuberculosis bacteria that grow slowly in phagocytes in an acidic environment. The antibacterial concentration of this product in vivo is 12.5 mu; g/ml, and 50 mu; g/ml can kill tuberculosis bacteria. The concentration of this product that inhibits tuberculosis bacteria in cells is 10 times lower than that outside the cells, and it has almost no antibacterial effect in neutral and alkaline environments. The mechanism of action may be related to pyrazinoic acid. After pyrazinamide penetrates into phagocytes and enters the tuberculosis bacteria, the amidase in the bacteria removes the amide group and converts it into pyrazinoic acid to exert an antibacterial effect. In addition, because pyrazinamide is similar to nicotinamide in chemical structure, it interferes with dehydrogenase by replacing nicotinamide, prevents dehydrogenation, and hinders the use of oxygen by tuberculosis bacteria, which affects the normal metabolism of bacteria and causes death.

Chemical name: pyrazinecarboxamide, molecular formula: C5H5N3O, molecular weight: 123.12.

This product is white or off-white tablets.

This product is only effective against mycobacteria and is used in combination with other anti-tuberculosis drugs (such as streptomycin, isoniazid, rifampicin and ethambutol) to treat tuberculosis.

Oral. The usual dosage for adults, combined with other anti-tuberculosis drugs, is 15-30 mg/kg daily or 50-70 mg/kg 2-3 times a week; the maximum daily dosage for daily use is 2 g, the maximum dosage for 3 times a week is 3 g each time, and the maximum dosage for 2 times a week is 4 g each time.

The more common symptoms are joint pain (caused by hyperuricemia, usually mild and self-limited). The less common symptoms are loss of appetite, fever, fatigue or weakness, yellow eyes or skin (hepatotoxicity), and chills.

Not yet clear.

Precautions for children: This product is highly toxic and should not be used by children. If it must be used, the pros and cons must be weighed before deciding. Precautions for pregnancy and lactation: Pregnant women with tuberculosis can first be treated with isoniazid, rifampicin and ethambutol for 9 months. If they are resistant to any of the above drugs but may be sensitive to this product, this product can be considered. This product is FDA Class C for pregnancy use. Precautions for the elderly: Not yet clear.

1. When used in combination with allopurinol, colchicine, probenecid, and sulfinpyrazone, pyrazinamide can increase the blood uric acid concentration and thus reduce the efficacy of the above drugs for gout. Therefore, the dose of the above drugs should be adjusted when used in combination with pyrazinamide to control hyperuricemia and gout. 2. When used in combination with ethionamide, adverse reactions may be enhanced. 3. When cyclosporine and pyrazinamide are used together, the blood concentration of the former may decrease, so the blood concentration needs to be monitored and the dose adjusted accordingly.

Keep away from light and store in sealed container.

0.5g

36 months