Efficacy of the Dietary Supplement S-Adenosyl-L-Methionine
Abstract
OBJECTIVE: To review existing published clinical evidence surrounding the dietary supplement SAMe (S-adenosyl-L-methionine). DATA SOURCES: The majority of information was obtained from primary published literature identified through MEDLINE search (1966–February 2001). Information was also obtained through secondary and tertiary sources when available. STUDY SELECTION AND DATA EXTRACTION: All articles identified from data sources were evaluated and all relevant information included in this review. DATA SYNTHESIS: The majority of clinical trial evidence surrounds the application of SAMe for various depressive disorders, osteoarthritis, and fibromyalgia. Sample sizes of these trials and the dose employed have varied considerably. Several reviews and at least two meta-analyses have examined the available evidence surrounding SAMe in the therapy of depression for trials completed prior to 1994 and concluded that SAMe was superior to placebo in treating depressive disorders and approximately as effective as standard tricyclic antidepressants. Much of this information exists in the form of isolated case reports or solitary clinical trials. SAMe appears to be well tolerated, with the majority of adverse effects presenting as mild to moderate gastrointestinal complaints. However, it is apparent that this agent is not without risk of more significant psychiatric and cardiovascular adverse events. Information documenting drug or food interactions with SAMe is very limited. CONCLUSIONS: Consumers should be instructed to avoid unmonitored consumption of this dietary supplement until sufficient discussion has taken place with their primary healthcare provider. Although there exists significant potential for therapeutic application of SAMe, its uncertain risk profile precludes definitive recommendation at this time. Healthcare providers and consumers should likely temper their enthusiasm for this dietary supplement until sufficient information becomes available.