Pearls

Vitamin B6 for tardive dyskinesia?

Current Psychiatry. 2018 October;17(10):42,47

References

1. Carbon M, Hsieh CH, Kane JM, et al. Tardive dyskinesia prevalence in the period of second-generation antipsychotic use: a meta-analysis. J Clin Psychiatry. 2017;78(3):e264-e278.
2. Smith Mosley LL, Mosely II JF, Fleischfresser JR, et al. Vesicular monoamine transporter type 2 (VMAT2) inhibitors in the management of tardive dyskinesia. Clin Med Rev Case Rep. 2017;4(12):1-5.
3. Adelufosi AO, Abayomi O, Ojo M. Pyridoxal 5 phosphate for neuroleptic-induced tardive dyskinesia. Cochrane Database Syst Rev. 2015;(4):CD010501.
4. Lerner V, Miodownik C, Kapstan A, et al. Vitamin B(6) in the treatment of tardive dyskinesia: a double-blind, placebo-controlled, crossover study. Am J Psychiatry. 2001;158(9):1511-1514.
5. Lerner V, Miodownik C, Kapstan A, et al. Vitamin B6 treatment for tardive dyskinesia: a randomized, double-blind, placebo-controlled, crossover study. J Clin Psychiatry. 2007;68(11):1648-1654.
6. Umar MU, Isa AA, Abba AH. High dose pyridoxine for the treatment of tardive dyskinesia: clinical case and review of literature. Ther Adv Psychopharmacol. 2016;6(2):152-156.
7. Miodownik C, Meoded A, Libov I, et al. Pyridoxal plasma level in schizophrenic and schizoaffective patients with and without tardive dyskinesia. Clin Neuropharmacol. 2008;31(4):197-203.
8. Miodownik C, Witztum E, Lerner V. Lithium-induced tremor treated with vitamin B6: a preliminary case series. Int J Psychiatry Med. 2002;32(1):103-108.
9. Lerner V, Bergman J, Statsenko N, et al. Vitamin B6 treatment in acute neuroleptic-induced akathisia: a randomized, double-blind, placebo-controlled study. J Clin Psychiatry. 2004;65(11):1550-1554.
10. Miller, BJ. Tardive dyskinesia: a review of the literature. Psychiatric Times. http://www.psychiatrictimes.com/articles/tardive-dyskinesia-review-literature. Published June 27, 2017. Accessed July 31, 2018.

Umar et al (2016)⁶ published a case review of a 29-year-old woman with treatment-resistant schizophrenia with TD who was treated with clozapine, 400 mg/d. She was started on vitamin B6, 450 mg/d, for 4 weeks, and then her dose was increased to 600 mg/d. At 6 months, she experienced a 78% reduction in the severity of her TD symptoms, as measured by the Abnormal Involuntary Movement Scale. The authors reported that this improvement was maintained for 1 year after vitamin B6 was stopped.

Miodownik et al (2008)⁷ reported in a study of 89 patients with schizophrenia that those with TD (n = 40) had diminished amounts of vitamin B6 in their plasma compared with patients without symptoms of motor disturbances (n = 49).

Vitamin B6 has been known to improve other psychotropic-induced movement disorders. In a study of lithium-induced tremors, treatment with pyridoxine, 900 to 1,200 mg/d, resulted in “impressive improvement until total disappearance of tremor.”⁸Lerner et al (2004)⁹ also reported significant improvement for patients with neuroleptic-induced akathisia who were treated with vitamin B6.

Some proposed mechanisms of action

Pyridoxal-5-phosphate is a coenzyme in the synthesis of dopamine and other neurotransmitters. This might explain in part the biochemical mechanism of vitamin B6 in attenuating motor symptoms following long-term dopamine blockade. Chronic neurotransmitter antagonism may result in an upregulation of dopamine receptors in response. This compensatory reaction might create a dopamine receptor super-sensitivity in the nigrostriatal pathways.¹⁰

Another potential mechanism of action might be vitamin B6’s potent antioxidant properties and its scavenging of free radicals. The neurotoxicity of oxidative stress has been implicated in various movement disorders and psychiatric conditions.

In all of the studies described here, patients continued to receive daily antipsychotic treatment. In these trials, the adverse effects of vitamin B6 were minimal or negligible. In one study, vitamin B6 was reported to have had a better adverse effect profile than placebo.⁴

Vitamin B6 for tardive dyskinesia?

References

Some proposed mechanisms of action

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