Pyrazinamide

A to Z Drug Facts

(peer-uh-ZIN-uh-mide)

PMS-Pyrazinamide, Tebrazid

Class: Anti-infective/Antitubercular

 Action Pyrazine analog of nicotinamide may be bacteriostatic or bactericidal against Mycobacterium tuberculosis.

 Indications Initial treatment of active tuberculosis in adults and selected children when combined with other antituberculosis agents.

 Contraindications Severe hepatic damage; acute gout.

 Route/Dosage

ADULTS: PO 15 to 30 mg/kg one time/day (maximum 2 gm/day) or 50 to 70 mg/kg 2 times/week (maximum 4 gm/dose). CHILDREN: PO 15 to 30 mg/kg once daily (maximum 2 gm/day).

 Interactions None well documented.

 Lab Test Interferences May interfere with Acetest and Ketostix urine tests, producing pinkbrown color.

 Adverse Reactions

DERM: Rash; acne; photosensitivity. GI: Nausea; vomiting; anorexia. HEPA: Hepatotoxicity. META: Gout; porphyria. OTHER: Arthralgia and myalgia; hypersensitivity reactions (urticaria, pruritus); fever.

 Precautions

Pregnancy: Category C. Lactation: Excreted in breast milk. Children: Safety and efficacy not established. Use only if therapy is essential. Diabetes mellitus: Management of diabetes mellitus may be more difficult. Hepatic function impairment: Closely follow patients with pre-existing liver disease or patients at increased risk (eg, alcohol abusers). It may be necessary to discontinue drug; do not resume therapy if signs of hepatocellular damage appear. Hyperuricemia: May inhibit renal excretion of urates, resulting in hyperuricemia.

 Administration/Storage

• Drug should always be part of multi-drug therapy to decrease chance of resistant organisms. Question doses > 35 mg/kg/day.
• Administer with food to decrease GI irritation.
• Store at room temperature in tightly closed, light-resistant container.

 Assessment/Interventions

• Obtain patient history, including drug history and any known allergies.
• Assess for signs of anemia (eg, hematocrit, hemoglobin, evidence of fatigue).
• Ensure that serum AST, ALT and uric acid concentration have been determined before beginning therapy and repeated q 2 to 4 wk.
• Obtain culture and sensitivity monthly to detect resistance and ensure sensitivity to medication.
• Monitor patient for signs of liver disease or gout.

 Patient/Family Education

• Emphasize need to be compliant with regimen and to not miss any doses.
• Explain that long-term therapy (6 mo to 2 yr) will be necessary.
• Inform diabetic patients that drug may interfere with urine ketone values.
• Emphasize importance of follow-up examinations to monitor effectiveness of therapy and identify side effects.
• Instruct patient to report the following symptoms to physician: Fever; loss of appetite; malaise; nausea and vomiting; darkened urine, yellowish skin or eye discoloration; pain or swelling joints.
• Advise patient to avoid intake of alcoholic beverages and alcohol-containing products.

Books@Ovid
Copyright © 2003 Facts and Comparisons
David S. Tatro
A to Z Drug Facts