We present two cases of patients with schizophrenia treated with minocycline. Minocycline (a second-generation tetracycline) is an established and safe broad-spectrum antibiotic that crosses the blood-brain barrier, with additional efficacy for diseases such as acne and rheumatoid arthritis. Animal studies have suggested that minocycline may prevent progression of some neurological disorders. Moreover, it has been reported that minocycline might have antidepressant effects. We report two cases of acute schizophrenia with predominant catatonic symptoms that responded to minocycline.