Pyrazinamide

Fact Checked

Medically reviewed by Kenny Cheuk Yin Cheung, Pharmacist

Last updated on 25/07/2021.

GENERIC NAME: Pyrazinamide

ALTERNATIVE NAME: PZA

CHINESE NAME: 吡嗪醯胺

BRAND NAME(S) IN HONG KONG: Pyrafat, Rifater (Isoniazid/Pyrazinamide/Rifampicin)

DRUG CLASS: Antitubercular agents

SUB CLASS: Antimycobacterials

USED FOR: Tuberculosis

AVAILABLE DOSAGE FORMS:
– 500mg (tablets)
– 50mg/300mg/120mg (tablets)

What is Pyrazinamide for?

Tuberculosis (TB) is an airborne infectious disease that involves mycobacterium tuberculosis bacteria. It can be either asymptomatic or symptomatic. Lung is the most common site for tuberculosis, but it can also affect other body parts. TB can be latent or active, and about one-tenth of latent tuberculosis patients may become active and infectious. Pyrazinamide disturbs the growth and proliferation of mycobacterium tuberculosis, thus killing it and treating tuberculosis. It can be used together with other antibiotics (Isoniazid, Rifampicin) to shorten the duration of the whole TB treatment. In Hong Kong, although newborn infants would get Bacillus Calmette–Guérin (BCG) vaccine for free, there might still be a chance to get infected.

How to use it?

Pyrazinamide is available in tablets for oral administration. It is administered for the initial 2 months of a 6-month or longer treatment regimen (including Isoniazid, Rifampicin, Streptomycin, Ethambutol)

For tuberculosis, in combination with other antitubercular drugs:
Once-daily dosing:
40-55 kg: 1000 mg once daily
56-75 kg: 1500 mg once daily
76-90kg: 2000 mg once daily

Twice-weekly dosing:
40-55 kg: 2000 mg twice weekly
56-75 kg: 3000 mg twice weekly
76-90kg: 4000 mg twice weekly

What are the side effects of Pyrazinamide?

Common side effects of Pyrazinamide include nausea, vomiting, arthralgia, and myalgia.

Who should not take Pyrazinamide?

– People who are allergic to Pyrazinamide or any component of the formulation.
– Patients with acute gout or severe liver damage.

Pharmacist Tips:

– Tuberculosis patients have to be treated for at least 9 months to eradicate all pathogens in the body, even if they are asymptomatic.
– Although more and more people are vaccinated against tuberculosis, personal hygienic measures are important since vaccination does not provide full protection.

Common dosing schedule:
Pyrazinamide can be taken with or without food.

This schedule is for reference only, adjustments may be made according to individual needs.

Some common medications Pyrazinamide may interact with:
– Cyclosporin

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Pyrazinamide in Hong Kong?

In Hong Kong, Pyrazinamide is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at https://www.drugoffice.gov.hk

Need more information?

For detailed information about the use of Pyrazinamide in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.