Can a patient who stopped taking hydrocortisone (corticosteroid) 10 mg, previously taken as 1.5 mg in the morning and 0.5 mg in the evening, 1 week ago cold turkey, restart at the same dose and are any laboratory tests needed?

Restarting Hydrocortisone After Abrupt Discontinuation

Yes, you can restart hydrocortisone at the same dose (15 mg in morning, 5 mg in evening) immediately, and you should check morning cortisol and ACTH levels before restarting to assess adrenal function recovery. 1

Understanding the Clinical Context

The patient was on a physiologic replacement dose of hydrocortisone (20 mg total daily, split as 15 mg AM/5 mg PM), which mimics normal cortisol production. 2 After one week off therapy, the key question is whether the hypothalamic-pituitary-adrenal (HPA) axis has recovered or if the patient remains at risk for adrenal insufficiency. 1

Critical Distinction: Primary vs Secondary Adrenal Insufficiency

• If this patient has primary adrenal insufficiency (Addison's disease), the adrenal glands themselves are damaged and will never recover—lifelong replacement is mandatory. 1
• If this patient has secondary adrenal insufficiency from prior exogenous corticosteroid use, the HPA axis can potentially recover after stopping steroids, though this takes time (often 3+ months). 1

Immediate Management

Restart Hydrocortisone Now

Resume the same dose immediately (15 mg morning, 5 mg evening) without tapering up. 3 The FDA labeling confirms that hydrocortisone dosing should be individualized based on disease and response, and after long-term therapy that is stopped, gradual withdrawal is recommended—but the reverse (restarting) does not require gradual escalation. 3

• The patient has been off therapy for only one week, which is insufficient time for the body to fully adapt if they have true adrenal insufficiency. 4
• Risk of adrenal crisis is real: patients with adrenal insufficiency have a 6-8% annual incidence of adrenal crisis, with mortality rates increased 2.19-fold in men and 2.86-fold in women. 1

Assess for Signs of Adrenal Crisis

Before restarting, evaluate the patient for symptoms of adrenal insufficiency that developed during the week off therapy:

• Hypotension (especially postural hypotension) 4
• Hyponatremia and hyperkalemia 5
• Weight loss, fatigue, nausea 4
• Hypoglycemia 4

If the patient shows signs of acute adrenal insufficiency or crisis, do not simply restart oral hydrocortisone—this requires emergency management with IV hydrocortisone 100 mg bolus followed by 100-300 mg/day as continuous infusion or divided doses every 6 hours, plus aggressive IV fluid resuscitation with 3-4 liters of normal saline. 4

Laboratory Testing

Essential Labs Before or Immediately After Restarting

Check these labs ideally before restarting hydrocortisone, or immediately after if clinical urgency requires starting first:

• Morning cortisol (8 AM) and ACTH level to assess whether the HPA axis has recovered. 1
• Serum sodium and potassium to evaluate for electrolyte abnormalities suggesting mineralocorticoid deficiency. 4
• Blood glucose to rule out hypoglycemia. 4

Interpretation Caveats

• Morning cortisol measurements are not diagnostic in patients already taking hydrocortisone, as therapeutic steroids interfere with the cortisol assay. 4, 1
• Hydrocortisone must be held for 24 hours before endogenous cortisol can be accurately assessed. 4
• ACTH stimulation testing is the gold standard for diagnosing adrenal insufficiency, but it can give false-negative results early in the course when adrenal reserve declines slowly. 4

Practical Approach

Since the patient needs immediate treatment, restart hydrocortisone now and plan for formal HPA axis testing in 3 months to determine if lifelong therapy is needed or if the axis has recovered. 4, 1 Testing at 3 months is recommended by oncology guidelines for patients with checkpoint inhibitor-induced adrenal insufficiency, and this principle applies broadly. 4

Ongoing Monitoring After Restart

Clinical Follow-Up

• Monitor for return of normal energy, stable weight, and normal blood pressure. 4
• Normal skin color (absence of hyperpigmentation in primary AI) indicates adequate replacement. 4
• Postural hypotension suggests inadequate mineralocorticoid replacement if this is primary adrenal insufficiency. 4

Laboratory Monitoring

• Serum sodium and potassium should normalize on adequate replacement. 4
• Cortisol day curves (measuring cortisol at 0,2,4, and 6 hours after morning dose) can help assess absorption and dosing adequacy if under-replacement is suspected. 4, 2

Critical Patient Education

All patients on hydrocortisone replacement must receive education on stress dosing to prevent adrenal crisis: 1

• Double the usual dose during minor illness (fever, infection, gastroenteritis). 1
• Use emergency hydrocortisone injection (100 mg IM) if vomiting or unable to take oral medication. 1
• Seek immediate medical attention for severe illness, trauma, or surgery—these require IV stress-dose steroids (hydrocortisone 100 mg IV bolus, then 200-300 mg/day). 4, 5, 6
• Wear a medical alert bracelet indicating adrenal insufficiency. 4, 1

Common Pitfalls to Avoid

• Do not delay restarting therapy while waiting for lab results if the patient has known adrenal insufficiency—this risks adrenal crisis. 4
• Do not attempt to "taper up" the dose—restart at full replacement dose immediately. 3
• Do not assume HPA axis recovery after only one week off steroids—recovery typically takes months. 1
• Do not forget mineralocorticoid replacement (fludrocortisone) if this is primary adrenal insufficiency—hydrocortisone alone does not provide adequate mineralocorticoid activity at physiologic doses. 4