Products
Pyrazinamide is commercially available in tablet form (Pyrazinamide Labatec, combination products). It was first used in the 1950s for the treatment of tuberculosis.
Structure and properties
Pyrazinamide (C5H5N3O, Mr = 123.1 g/mol) exists as a white crystalline powder that is sparingly soluble in water. It is a 1,4-pyrazine and an amide. Pyrazinamide is an analog of nicotinamide, which itself shows weak antibacterial properties against the mycobacteria.
Effects
Pyrazinamide (ATC J04AK01) has antituberculous (bacteriostatic to bactericidal) properties against the causative agent of tuberculosis, . It is primarily effective against slow-growing pathogens. Against, on the other hand, it is hardly active. The half-life is in the range of 6 to 10 (to 17) hours. The effects are attributed to enzymatic and intrabacterial conversion to pyrazine carboxylic acid, which accumulates in bacteria.
Indications
For the treatment of tuberculosis in combination with other tuberculostatics.
Dosage
According to the professional information. The tablets are taken once a day after meals and with sufficient liquid (a glass of water). The skin should be protected from the sun during treatment because photosensitivity may occur as an adverse effect.
Contraindications
- Hypersensitivity
- Children under 3 years only if vital indication.
- Porphyria
- Acute liver disease (hepatitis)
- Up to 6 months after surviving hepatitis.
- History of isoniazid-related drug-induced hepatitis.
- Gout, hyperuricemia
- Renal insufficiency
- Pregnancy, lactation
Full details of precautions and interactions can be found in the drug label.
Interactions
Alcohol should not be consumed during treatment. Pyrazinamide is a substrate of CYP450 isozymes.
Adverse effects
The most common possible adverse effects include:
- Lack of appetite, abdominal pain, nausea.
- Flush
- Muscle pain, joint pain
- Discomfort
Pyrazinamide can increase liver enzymes, cause liver dysfunction, and rarely cause severe hepatotoxic side effects. As with other antibiotics, resistance is a problem.