PYRAZINAMIDE

DOSAGE

Adults (<50kg): 1.5g once a day (oral); or for DOT supervised regimen: 2g three times a week (oral).

Adults (50kg+): 2g once a day (oral); or for DOT supervised regimen: 2.5g three times a week (oral).

Children: 35mg/kg (max. 1.5g if <50kg; 2g if 50kg+) once a day (oral); or for DOT supervised regimen: 50mg/kg (max. 2g if <50kg; 2.5g of 50kg+) three times a week (oral). (Doses should be rounded up to facilitate administration of suitable volumes of liquid or an appropriate strength of tablet)

Pyrazinamide may be taken with or without food.

PREPARATIONS

Oral:      500mg tablets.

                Liquid (as a manufactured ‘special’ - unlicensed medicine).

                Rifater tablets (rifampicin 120mg, isoniazid 50mg, pyrazinamide 300mg).

Voractiv® tablets (rifampicin 150mg, isoniazid 75mg, pyrazinamide 400mg, ethambutol 275mg).

For paediatric oral fixed dose combinations (dissolvable in water) click here

DRUG LEVEL MONITORING

Indications for monitoring:

·         Known or suspected malabsorption.

·         Poor treatment response.

Target Level:      20 – 40mg/L(Peak).

Timing of sample:

·         2 hours post dose.

·         Repeat at 6 hours if suspect delayed.

Frequency of Levels:

·         Drug levels need not be routinely measured.

ADVERSE EFFECTS

COMMON:

Hyperuricaemia.

Arthralgia.
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Gastrointestinal: Anorexia, nausea, vomiting.

Hepatic: Transient increases in LFTs.

Dermatological: Rash.

SERIOUS:

Haematological: Sideroblastic anaemia (rare), thrombocytopaenia (rare).

Hepatotoxity.

ADVERSE EFFECTS: MONITORING

Routine tests as per generic MDR-TB treatment monitoring guidelines.

INTERACTONS

Probenecid: Pyrazinamide antagonises the effect of probenecid.

Sulfinpyrazone: Pyrazinamide antagonises the effect of sulfinpyrazone.

This information is not inclusive of all drug interactions. Please discuss with a pharmacist.

CONTRA-INDICATIONS & CAUTIONS

Contraindications:

Hypersensitivity: To pyrazinamide.

Cautions:

Gout.

Liver Disease.

LABORATORY INFORMATION

Please find up to date information at www.assayfinder.com regarding individual providers of drug level monitoring tests. Click on the provider to discover contact details.  Turnaround time varies depending on the test and whether it is run locally or sent to an external lab.  By contacting laboratories in advance, turnaround time can significantly be reduced.

Sample Type: Serum.

Volume Required: 2 ml.

Sample Container: Plain (non SST).

Container Type: Any.

Availability: Office Hours.

Turnaround Time: 7 Days.