✅ Active Ingredient Overview Table:

🔬 Active Ingredient (Generic Name):	Pyrazinamide
💊 Indication:	Tuberculosis (TB) – Intensive Phase of Treatment
🇺🇸 US Brand Equivalent:	Pyrazinamide (Generic) – available as part of first-line TB regimens
🏭 Manufacturer:	Lupin Limited (Founded: 1968)
📦 Packaging:	10 Tablets per Strip
🧪 Strengths:	750 mg, 500 mg
🚚 Delivery Time:	6–15 days

🌿 What is Pyrazinamide?

Pyrazinamide (PZA) is a first-line antitubercular agent used during the intensive phase of TB therapy. It functions best in the acidic environment of macrophage phagolysosomes and necrotic lesions, where it converts to its active form, pyrazinoic acid, inhibiting Mycobacterium tuberculosis growth. Pyrazinamide’s unique mechanism targets semi-dormant bacilli, shortening overall TB treatment duration when combined with isoniazid, rifampicin, and ethambutol.

🧬 Pharmacology & Mechanism of Action

Attribute	Detail
Chemical Formula	C5H5N3O
Molecular Weight	123.12 g/mol
Mechanism	Prodrug converted by mycobacterial pyrazinamidase (PncA) to pyrazinoic acid → accumulates in M. tuberculosis → disrupts membrane potential and inhibits fatty acid synthase I → bactericidal in acidic environments.
Absorption	~90% oral bioavailability; food increases absorption slightly
Distribution	Widely distributed in tissues and fluids; penetrates caseous lesions
Metabolism	Hepatic deamidation to pyrazinoic acid; further hydroxylation in liver
Excretion	Primarily renal (up to 70% as metabolites)
Half-Life	9–10 hours (may be prolonged in renal impairment)

💡 Indications & Dosing

Phase	Dosage & Regimen (Adults)
Intensive Phase	• Standard Regimen: 25 mg/kg once daily (500 mg or 750 mg tablet based on body weight) for first 2 months of therapy.
Pediatric Dosing	• 15–30 mg/kg once daily (rounded to nearest 50 mg) as part of combination regimen.

Administration: Take with food to reduce gastrointestinal upset and improve absorption.
Combination Therapy: Always used with Rifampicin, Isoniazid, and Ethambutol during intensive phase.
Treatment Duration: Generally administered for the initial 8 weeks (56 doses) of TB therapy, followed by continuation phase with Isoniazid and Rifampicin for an additional 4–7 months depending on regimen.

⚠️ Warnings & Side Effects

Common Adverse Effects:

Hepatotoxicity (elevated transaminases; monitor LFTs monthly)
Hyperuricemia → gout flares (monitor serum uric acid)
Gastrointestinal upset (nausea, vomiting, anorexia)

Less Common:

Arthralgia
Photosensitivity rash

Serious (Rare):

Severe hepatotoxicity → acute liver failure (discontinue if LFTs >5× ULN or symptomatic hepatitis)
Severe cutaneous adverse reactions (e.g., Stevens-Johnson syndrome)
Arthralgia with hyperuricemia leading to acute gouty arthritis

Precautions:

Baseline Evaluation: LFTs, renal function, serum uric acid, and complete blood count.
Monitoring: Check LFTs monthly; monitor for symptoms of hepatotoxicity (fatigue, anorexia, abdominal pain, jaundice).
Renal Impairment: Dose adjustment or increased dosing interval may be required; consult nephrology if CrCl <30 mL/min.
Pregnancy & Breastfeeding: Category C; use only if benefit outweighs risk; limited data on teratogenicity.

🏥 Storage Instructions

Store Pyzina tablets at 20–25°C in a dry, dark place. Keep tablets in original blister packaging until use to protect from moisture. Keep out of reach of children.

🌐 Availability & Purchasing

✅ United States: Pyrazinamide is available by prescription only as part of combination TB drug regimens.
✅ United Kingdom & EU: Prescription-only; integrated into national TB control programs.
✅ Australia: Available under prescription; regulated through TB specialist clinics.

Importing Pyzina from India:
Purchasing Pyzina 500 mg or 750 mg from India can significantly reduce costs. Ensure a valid prescription and compliance with local import regulations to avoid customs issues.

🔗 Authoritative Resources

🔗 Antitubercular Therapies (Indian Brands)

Isonex 100 mg – Isoniazid by Lupin Ltd.
R-Cinex 300/450 mg – Isoniazid/Rifampicin by Lupin Ltd.

🎥 Educational Video on TB Intensive Phase Therapy

👨‍⚕️ Expert Insight: Dr. Anjali Mehta, Infectious Disease Specialist

“Pyrazinamide’s unique ability to kill semi-dormant mycobacteria in acidic environments allows TB therapy to be shortened. However, close monitoring for hepatotoxicity is crucial to ensure patient safety.”