Systemic corticosteroids, such as dexamethasone, are well-documented to cause a wide range of dose-dependent neuropsychiatric adverse effects. These can range from mild mood changes and insomnia to severe reactions like mania, depression, delirium, and frank psychosis, often termed "steroid psychosis." The symptoms described in the question—emotional lability, hallucinations, mania, and mood swings—are classic manifestations. The patient's high dose of dexamethasone (32 mg/day) and advanced age increase this risk significantly. While other medications listed can cause CNS disturbances, the specific constellation of symptoms, particularly mania and significant mood swings, is most characteristic of corticosteroid therapy.

A. Lisinopril: While mood changes can occur, ACE inhibitors are not commonly associated with causing severe psychotic episodes.

C. Famotidine: Can cause confusion and delirium, especially in elderly patients with renal impairment, but is less likely to induce mania or a full psychotic syndrome.

D. Metoclopramide: Can cause CNS effects like confusion and hallucinations, but is more characteristically associated with extrapyramidal symptoms and tardive dyskinesia.

E. Hydromorphone: Opioids are a common cause of sedation, confusion, and delirium in the elderly, but are less frequently implicated in causing mania or complex mood disorders.

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O. P.

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depression

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T. P.

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J. M. (2006). Psychiatric adverse effects of corticosteroids. Mayo Clinic Proceedings

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1361–1367. (See Table 1

page 1362). This article categorizes the psychiatric adverse effects of corticosteroids

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mania

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