What are the key considerations before prescribing Diamox (Acetazolamide)?

Key Considerations Before Prescribing Diamox (Acetazolamide)

Before prescribing Diamox (acetazolamide), carefully evaluate for contraindications including hypersensitivity to sulfonamides, depressed sodium/potassium levels, kidney/liver disease, and angle-closure glaucoma. 1

Contraindications

• Hypersensitivity to acetazolamide or any sulfonamide derivatives due to potential cross-sensitivity 1
• Depressed sodium and/or potassium blood serum levels 1
• Marked kidney or liver disease/dysfunction 1
• Suprarenal gland failure 1
• Hyperchloremic acidosis 1
• Cirrhosis (due to risk of hepatic encephalopathy) 1
• Long-term use in chronic non-congestive angle-closure glaucoma (may mask worsening glaucoma while permitting organic closure of the angle) 1

Dosing Considerations

• For acute mountain sickness (AMS) prevention:

  • Standard dosing: 125 mg twice daily starting 24 hours before ascent 2
  • For rapid ascents to elevations >3,500 m, higher doses (500-750 mg/day) may be more effective 3
  • Lower doses (62.5 mg twice daily) have been shown to be less effective than standard dosing 4

• For glaucoma:

  • Individualize dosing based on intraocular pressure response 1

• For epilepsy:

  • Used as adjunctive therapy with other antiepileptic medications 5
  • Monitor for development of tolerance to antiepileptic effects 5

Monitoring Requirements

• Assess renal function and electrolytes before initiating therapy 6
• Monitor for metabolic acidosis, especially with long-term use 5
• Consider periodic monitoring of serum electrolytes, particularly in patients at risk for electrolyte disturbances 1

Drug Interactions

• Use caution when combining with other diuretics as synergistic effects may occur 6
• May potentiate effects of other carbonic anhydrase inhibitors 1

Adverse Effects to Monitor

• Paresthesias 5
• Kidney stones (urolithiasis) 5
• Metabolic acidosis 5
• Lethargy and appetite suppression 5
• Rare blood dyscrasias 5
• Electrolyte disturbances, particularly hypokalemia 6

Special Populations

• Pediatric patients: Use caution and adjust dosing based on weight 6
• Elderly patients: Consider starting at lower doses due to potential for decreased renal function 6
• Patients with renal impairment: Use with caution; may require dose adjustment 1

Clinical Pearls

• Acetazolamide is a carbonic anhydrase inhibitor with multiple clinical applications including glaucoma, epilepsy, and altitude sickness prevention 7
• For diuretic-resistant edema, acetazolamide may be considered as part of combination therapy 6
• When used for AMS prevention, acetazolamide works by increasing arterial oxygen concentrations 7
• Drug concentration monitoring is not routinely beneficial in epilepsy management 5

By carefully considering these factors before prescribing Diamox, you can optimize treatment efficacy while minimizing potential adverse effects.