Home Drug Guide Allopurinol

Drug Guide

Generic Name

Allopurinol

Brand Names Zyloprim, Lopurin

Classification

Therapeutic: Antigout agent

Pharmacological: Xanthine oxidase inhibitor

FDA Approved Indications

  • Gout prophylaxis
  • Lixisenatide (related to gout prevention)
  • Kidney stones related to uric acid
  • Increased uric acid due to chemotherapy

Mechanism of Action

Inhibits xanthine oxidase enzyme, reducing uric acid production

Dosage and Administration

Adult: Initially 100 mg daily, titrate up to 300-600 mg daily based on serum uric acid levels.

Pediatric: Not typically used in children unless for tumor lysis syndrome, dose individualized.

Geriatric: Start at lower doses due to potential renal impairment.

Renal Impairment: Adjust dose based on renal function; cautious use in severe impairment.

Hepatic Impairment: Use with caution; no specific dose adjustment but monitor liver function.

Pharmacokinetics

Absorption: Well absorbed orally, peak levels in 1-2 hours.

Distribution: Distributed widely, crosses placenta and enters breast milk.

Metabolism: Minimal hepatic metabolism, mostly excreted unchanged.

Excretion: Renally excreted, requires dose adjustment in renal impairment.

Half Life: Approximately 2 hours in healthy individuals, prolonged in renal impairment.

Contraindications

  • Hypersensitivity to allopurinol
  • Acute gout attacks (should be initiated after attack subsides)

Precautions

  • Renal or hepatic impairment
  • History of hypersensitivity reactions, including skin reactions
  • Risk of severe skin reactions like Stevens-Johnson syndrome (HLA-B*58:01 allele)

Adverse Reactions - Common

  • Rash (Common)
  • Gastrointestinal upset (Common)

Adverse Reactions - Serious

  • Severe skin reactions (Stevens-Johnson syndrome, Toxic epidermal necrolysis) (Rare)
  • Hepatotoxicity (Rare)
  • Hematologic abnormalities (agranulocytosis, aplastic anemia) (Rare)

Drug-Drug Interactions

  • Azathioprine, mercaptopurine (risk of toxicity due to decreased metabolism)
  • Theophylline (altered levels)

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor serum uric acid, renal and liver function, skin for reactions.

Diagnoses:

  • Risk for gout attacks during initiation
  • Impaired skin integrity

Implementation: Start at low dose, titrate as needed, monitor labs and clinical status.

Evaluation: Serum uric acid levels, renal function, and skin condition.

Patient/Family Teaching

  • Take medication with plenty of fluids to prevent kidney stones.
  • Report any skin rash or allergic reactions immediately.
  • Adhere to scheduled monitoring appointments.

Special Considerations

Black Box Warnings:

  • Severe dermatologic reactions, including Stevens-Johnson syndrome, toxic epidermal necrolysis, and hypersensitivity reactions. Increased risk in certain HLA alleles (HLA-B*58:01).

Genetic Factors: HLA-B*58:01 allele screening recommended in certain populations (e.g., Han Chinese, Korean, Thai) before initiation.

Lab Test Interference: Can falsely elevate serum uric acid measurements in some assays.

Overdose Management

Signs/Symptoms: Gastrointestinal symptoms, hypersensitivity reactions.

Treatment: Supportive care, monitor renal function, and consider hemodialysis in severe cases.

Storage and Handling

Storage: Store at room temperature, away from moisture and light.

Stability: Stable under recommended storage conditions.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.