Background: Patients with diabetes frequently use complimentary and alternative medications including Ayurvedic medications and hence it is important to determine their efficacy and safety.
Objectives: To assess the effects of Ayurvedic treatments for diabetes mellitus.
Search methods: We searched The Cochrane Library (issue 10, 2011), MEDLINE (until 31 August 2011), EMBASE (until 31 August 2011), AMED (until 14 October 2011), the database of randomised trials from South Asia (until 14 October 2011), the database of the grey literature (OpenSigle, until 14 October 2011) and databases of ongoing trials (until 14 October 2011). In addition we performed hand searches of several journals and reference lists of potentially relevant trials.
Selection criteria: We included randomized trials of at least two months duration of Ayurvedic interventions for diabetes mellitus. Participants of both genders, all ages and any type of diabetes were included irrespective of duration of diabetes, antidiabetic treatment, comorbidity or diabetes related complications.
Data collection and analysis: Two authors independently extracted data. Risk of bias of trials was evaluated as indicated in the Cochrane Handbook for Systematic Reviews of Intervention.
Main results: Results of only a limited number of studies could be combined, in view of different types of interventions and variable quality of data. We found six trials of proprietary herbal mixtures and one of whole system Ayurvedic treatment. These studies enrolled 354 participants ( 172 on treatment, 158 on controls, 24 allocation unknown). The treatment duration ranged from 3 to 6 months. All these studies included adults with type 2 diabetes mellitus.With regard to our primary outcomes, significant reductions in glycosylated haemoglobin A1c (HbA1c), fasting blood sugar (FBS) or both were observed with Diabecon, Inolter and Cogent DB compared to placebo or no additional treatment, while no significant hypoglycaemic response was found with Pancreas tonic and Hyponidd treatment. The study of whole system Ayurvedic treatment did not provide data on HbA1c and FBS values. One study of Pancreas tonic treatment did not detect a significant change in health-related quality of life. The main adverse effects reported were drug hypersensitivity (one study, one patient in the treatment arm); hypoglycaemic episodes (one study, one participant in the treatment arm; none had severe hypoglycaemia) and gastrointestinal side effects in one study (1 of 20 in the intervention group and 0 of 20 participants in the control group). None of the included studies reported any deaths, renal, hematological or liver toxicity.With regard to our secondary outcomes, post prandial blood sugar (PPBS) was lower among participants treated with Diabecon, was unchanged with Hyponidd and was higher in patients treated with Cogent DB. Treatment with Pancreas tonic and Hyponidd did not affect lipid profile significantly, while patients treated with Inolter had significantly higher HDL- and lower LDL-cholesterol as well as lower triglycerides. Cogent DB treated participants also had lower total cholesterol and triglycerides.Studies of treatment with Diabecon reported increased fasting insulin levels; one study of treatment with Diabecon reported higher stimulated insulin levels and fasting C-peptide levels in the treatment group. There was no significant difference in fasting and stimulated C-peptide and insulin levels with Hyponidd, Cogent DB and Pancreas tonic treatment. The study of Inolter did not assess these outcomes.No study reported on or was designed to investigate diabetic complications, death from any cause and economic data.
Authors' conclusions: Although there were significant glucose-lowering effects with the use of some herbal mixtures, due to methodological deficiencies and small sample sizes we are unable to draw any definite conclusions regarding their efficacy. Though no significant adverse events were reported, there is insufficient evidence at present to recommend the use of these interventions in routine clinical practice and further studies are needed.