S-adenosyl-l-methionine (SAMe) as antidepressant: meta-analysis of clinical studies

Introduction: S-adenosyl-l-methionine (SAMe) is a naturally-occurring substance which is a major source of methyl groups in the brain.

Material and methods: We conducted a meta-analysis of the studies on SAMe to assess the efficacy of this compound in the treatment of depression compared with placebo and standard tricyclic antidepressants.

Results: Our meta-analysis showed a greater response rate with SAMe when compared with placebo, with a global effect size ranging from 17% to 38% depending on the definition of response, and an antidepressant effect comparable with that of standard tricyclic antidepressants.

Conclusion: The efficacy of SAMe in treating depressive syndromes and disorders is superior with that of placebo and comparable to that of standard tricyclic antidepressants. Since SAMe is a naturally occurring compound with relatively few side-effects, it is a potentially important treatment for depression.