Abstract
BACKGROUND: Severe depressive disorder is among most debilitating condition. Conventional pharmacotherapy usually takes several weeks (usually 4-12 weeks) to improve symptoms. Ketamine is an N-methyl-D aspartate receptor antagonist having rapid action on depressive symptoms. OBJECTIVES: The effect of subanesthetic dose of ketamine was assessed on depressive and anxiety symptoms. Illness severity and improvement were assessed after treatment with ketamine. MATERIALS AND METHODS: Twenty-five drug-free/naïve patients of the male sex, with severe depression having no previous history of psychotic disorder, head injury, organic disorder, cardiological problem, or substance abuse were admitted for the study. Assessments were made at baseline and injection ketamine hydrochloride was given at a subanesthetic dose of 0.5 mg/kg intravenous bolus after preparation. Assessments were repeated 1 h after the first dose. Six doses were given over 2 weeks and assessments were repeated. Final assessments were made after 1 month of the last dose. RESULTS: There was a significant improvement in depression, anxiety, and the severity of illness after 2 weeks and 1 month of the last dose of ketamine. Significant improvement at 1 (st) h of the first dose was seen in depression and anxiety and not for illness severity. There were transient adverse effects observed in some patients which subsided within 1 h. CONCLUSION: Ketamine has a robust and rapid effect on depression, which was seen immediately after the administration of ketamine and sustained at the end of 1 month.