Adjuvant galantamine administration improves negative symptoms in a patient with treatment-refractory schizophrenia

Because of the demonstration of a selective a, nicotinic receptor abnormality in patients with schizophrenia, galantamine was added to the stable regimen of atypical and other antipsychotic medications in a 43-year-old man manifesting severe and persistent positive and negative symptoms, as well as mood disturbance and cognitive dysfunction. Galantamine is an inhibitor of acetylcholinesterase and a positive allosteric modulator of nicotinic cholinergic receptors (with a FDA-approved indication for the treatment of patients with mild to moderate Alzheimer disease (AD) under the trade name Reminyl). Galantamine HBr was initiated at a dose of 4 mg po BID, which was maintained for the first week of adjuvant therapy, and eventually was increased to 12 mg po BID during the final weeks of his 2-month trial. Remarkably, within I week of its initiation, there was a dramatic and clinically significant decrease of negative symptoms, as reflected in formal ratings on the Scale for the Assessment of Negative Symptoms. Moreover, within a few days of galantamine discontinuation, negative symptoms worsened, returning to the baseline level of severity. In addition to targeting memory dysfunction in AD, acetylcholinesterase inhibitors may have an expanded range of targets and clinical indications, including behavioral and psychotic symptoms. Galantamine is distinguished from other acetylcholinesterase inhibitors by its positive allosteric modulatory properties, improving the efficiency of transduction of the acetylcholine signal at nicotinic receptors. This latter property may have contributed to the observed improvement in negative symptoms observed in this patient. Importantly, positive symptoms were unchanged during this 2-month trial.