[Adrenal crisis associated with modafinil use]

Area of Science:

• Endocrinology
• Pharmacology

Background:

• Adrenal crisis is a life-threatening emergency resulting from adrenal insufficiency.
• CYP3A4-inducing drugs can accelerate hydrocortisone clearance, potentially precipitating adrenal crisis.

Observation:

• An 85-year-old woman with secondary adrenal insufficiency developed symptoms of adrenal crisis (asthenia, hyponatremia, hypotension) after starting modafinil.
• Symptoms rapidly improved upon modafinil cessation and intravenous hydrocortisone administration.

Findings:

• Modafinil, a CYP3A4 inducer, likely precipitated the adrenal crisis by increasing hydrocortisone metabolism.
• Other potential triggers such as infection or medication non-adherence were ruled out.

Implications:

• This case highlights the critical need to consider drug interactions, specifically CYP3A4 induction, in managing adrenal insufficiency.
• Steroid replacement doses may require adjustment in patients concurrently treated with metabolism-inducing medications like modafinil.