Category:

• Antigout agent; uricosuric

Description:

• Increases urinary excretion of uric acid; inhibits tubular penicillin and most cephalosporin secretion (increasing plasma levels)

Indications:

• Hyperuricemia associated with gout and gouty arthritis

• Elevation of plasma penicillin concentrations

• Elevation of plasma cephalosporin concentrations

Contraindications:

• Children under age 2

• Blood dyscrasias

• Uric acid kidney stones

• Moderate to severe renal impairment (CrCl <10ml/min)

Precautions:

• Pregnancy category B

• History of peptic ulcer

Adverse Reactions (Side Effects):

• Central Nervous System: dizziness, headache

• Gastrointestinal: anorexia, nausea, sore gums, vomiting

• Genitourinary: costovertebral pain, hematuria,mephrotic syndrome, renal colic, uric acid stones, urinary frequency

• Hematological: Anemia, aplastic anemia, hemolytic anemia

• Flushing, rash, hypersensitivity reactions  

Dosage:

Oral tablets

•  Adult:

  • Hyperuricemia:

    • 250mg twice daily for 7 days; increase to 500mg twice daily; increase every 4 weeks as needed to a maximum of 2-3 grams daily.

  • Penicillin or cephalosporin therapy:

    • 500mg four times daily

• Children: 

  • Penicillin or cepharlosporin therapy:

    • 25mg/kg/day initially; 40mg/kg/day divided four times daily