PHILADELPHIA--Vitamin B6 combined with the tetracyclic antidepressant drug mianserin can provide some relief of symptoms associated with neuroleptic-induced akathisia (NIA)--a state of agitation, stress or restlessness--according to recent research published in Clinical Neuropharmacology (29, 2:68-72, 2006).

Working under the premise that acute NIA patients often fail to respond to general NIA therapies, including anticholinergic (antimuscarinic) agents, dopamine agonists, GABAergic agents, [beta]-blockers, benzodiazepines and serotonin antagonists, researchers designed a study to compare the efficacy of B6, mianserin and placebo in the treatment of acute NIA. They randomly assigned 60 schizophrenia and schizoaffective inpatients, who also had acute NIA, to receive 1,200 mg/d vitamin B6, 15 mg/d mianserin or placebo for five days, in a double-blind design. Both at baseline and daily, they assessed the severity of NIA and psychotic symptoms using the Barnes Akathisia Rating Scale, Brief Psychiatric Rating Scale and Clinical Global Impression.

Compared with the placebo group, the vitamin B6 and mianserin groups showed a significant improvement in the subjective, subjective distress and global subscales; the objective subscale did not show significant positive results, but there was a trend toward symptom amelioration in both groups. A reduction of at least 2 points on the Barnes Akathisia Rating Scale global subscale was noted in the vitamin B6 group (13/23, 56 percent) as well as in the mianserin groups (13/20, 65 percent), but in only one patient in the placebo group (1/17, 6 percent). The researchers concluded a high dose of B6 and a low dose of mianserin may be effective adjuncts to current treatments of NIA. They added the efficacy of vitamin B6 and mianserin suggests that the pathophysiology of acute NIA is heterogeneous with the various subtypes of acute NIA responding differently to various pharmacological approaches.