Febuxostat

Febuxostat is a medicine used to treat and prevent gout. Gout happens when there is too much uric acid in your body and it forms into crystals which can appear around your joints leading to painful and swollen joints. This medicine helps to keep uric acid levels low.

Febuxostat is a xanthine oxidase inhibitor. It works by decreasing blood uric acid, which is the chemical that causes gout.

• Gout: Indicated for chronic management of hyperuricemia in patients with gout; not recommended for asymptomatic hyperuricemia.

Drugs used in Gout

Xanthine Oxidase Inhibitor

Febuxostat is a non-purine, selective xanthine oxidase (XO) inhibitor. It decreases serum uric acid level by inhibiting xanthine oxidase, which is responsible for uric acid production. Xanthine oxidase breaks down hypoxanthine to xanthine and thus to uric acid.

Febuxostat selectively inhibits xanthine oxidase, the enzyme that catalyses the conversion of hypoxanthine to xanthine to uric acid, thereby decreasing serum concentrations of uric acid.

Adult Dose (Oral):

• Chronic Gout: Initial: 40 mg/day; maintenance: 40-80 mg/day; increase if serum uric acid >6 mg/dL after 2 weeks.
• Tumor Lysis Syndrome: 120 mg once daily (start 2 days before cytotoxic therapy, minimum 7 days).

Mild-Moderate Hepatic Impairment (Child-Pugh A/B): No dosage adjustment needed.

Mild-Moderate Renal Impairment (CrCl 30-89): No dosage adjustment needed.

Take this medicine in the dose and duration as advised by your doctor. Swallow it as a whole. Do not chew, crush or break it. Febuxostat may be taken with or without food, but it is better to take it at a fixed time.

If you miss a dose of Febuxostat, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular schedule. Do not double the dose.

Common Side Effects:

• Diarrhea
• Headache
• Increased liver enzymes
• Nausea
• Skin rash
• Gout flares
• Edema

Precautions:

• Febuxostat may cause dizziness, sleepiness, blurred vision which may affect driving ability.
• Prescribed to reduce episodes of gout attack.
• Take at the same time every day.
• Take plenty of fluids (2-3 litres) daily.
• When first starting, you might have more gout attacks; do not stop on having an acute attack.
• Avoid alcohol (may cause gout flare).
• Stop and inform doctor if symptoms like rash, itchiness, breathing difficulties, fever or swelling occur.
• Flare prophylaxis with NSAID or colchicine for up to 6 months recommended.
• Monitor for signs and symptoms of MI and stroke.
• Monitor liver function tests periodically.

Contraindications:

• Patients being treated with azathioprine, mercaptopurine, or theophylline
• Hypersensitivity

Drug Interactions:

• Mercaptopurine, Azathioprine: May increase plasma concentrations (concomitant use not recommended).
• Theophylline: Alteration of metabolism.
• NSAIDs, Probenecid (glucuronidation inhibitors): May affect elimination.
• Warfarin: No dose adjustment needed.

Food Interactions: Caution is advised when consuming alcohol; consult your doctor.

Use in Pregnancy: Category C; febuxostat may be unsafe; animal studies have shown harmful effects on the developing baby.

Use in Lactation: Febuxostat is probably unsafe; limited data suggests drug may pass into breastmilk and harm the baby.

Pediatric Use: Safety and efficacy in children under 18 years have not been established.

Geriatric Use: No specific dosage adjustment is necessary for elderly patients.

Renal Impairment: Mild-moderate: no adjustment; severe: limited data.

Hepatic Impairment: Mild-moderate: no adjustment; severe: limited data.

Overdose: Studied in healthy subjects at doses up to 300 mg daily for seven days without evidence of dose-limiting toxicities.

Storage: Keep below 30 degree C, away from light and moisture. Keep out of reach of children.

Febuxostat