Steroid is commonly used for various connective tissue diseases and immunological related disorders. Psychiatric side effects are common in patient with systematic treatment of steroid. The reported prevalence ranges from 6% to 28%. Antidepressant-induced mania occurs when the mood of a patient switches to manic or hypomanic from depression after the use of antidepressant. We reported a case of a 55 year old lady, who presented with agitation and grandiosity after the treatment with antidepressant. She was initially diagnosed as having Bell’s palsy with unilateral facial muscle weakness. Oral prednisolone was prescribed for seven days where she became depressed, having auditory hallucination and delusion of guilt. She was then started on antidepressant where she became irritable, agitated and developed grandiose delusion. The antidepressant was withheld and she was started on atypical antipsychotic. Her condition improved and discharged well after three days of stay in the ward.