¹Monash Health, Department of Consultation Liaison Psychiatry and Department of Nephrology, Melbourne, Australia, ²Monash University, Department of Psychiatry, Melbourne, Australia

Background: Folate augmentation of antidepressants has been a recognised treatment strategy in psychiatric practice for Difficult-To-Treat Depression, for well over a decade, yet few psychiatrists use this strategy, nor know the difference between the different forms of folate. L-Methylfolate is the biologically active form of folate and has been readily available in Australia and around the world for over 10 years.

Aims & Objectives: This presentation explores the factors which may affect the use of this strategy, the current evidence base, and future directions in research and clinical practice.

Method: Overview of folate metabolism. Case presentations.

Results: L-Methylfolate can be useful for patients with depression who have low or normal folate levels. There is no long-term safety data for high-dose L-Methylfolate. Low-dose L-Methylfolate appears effective, safe, well-tolerated and has high acceptance for targeted patients, as well as being low-cost and readily available. Currently, no clinical practice guidelines exist for the prescribing of L-Methylfolate.

Discussion & Conclusions: L-Methylfolate is under-utilised as an augmentation strategy for depression. It has the potential to substantially improve the clinical outcomes for many of our patients with Difficult-To-Treat Depression. Psychiatrists world-wide should consider this simple and effective strategy for their patients. The development of clinical practice guidelines would be helpful. Further research in L-Methylfolate augmentation and monotherapy will consolidate and expand the evidence base to inform clinical practice.