Safety and Dose-Related Glycemic Signals of a Gymnema inodorum-Based Beverage in Type 2 Diabetes: An Open-Label Randomized Pilot Study
DOI:
https://doi.org/10.59796/jcst.V16N3.2026.203Keywords:
type 2 diabetes mellitus, Gymnema inodorum, safety, glycemic control, randomized clinical trial, herbal beverageAbstract
Gymnema inodorum is a popular traditional remedy for diabetes, yet clinical safety data for multi-herb beverages combined with metformin remain limited. This 12-week, open-label, randomized pilot study compared two daily doses of a G. inodorum–mulberry–chamomile beverage in adults with recently diagnosed type 2 diabetes mellitus (≤6 months since diagnosis) receiving stable metformin monotherapy. Thirty-two T2DM patients receiving metformin were assigned to consume the beverage at 150 mL/day (Group A) or 300 mL/day (Group B). The primary outcomes assessed safety markers, including hematology and hepatic and renal function. Secondary outcomes included fasting blood glucose (FBG), HbA1C, and oral glucose tolerance test (OGTT) indices. The beverage was generally well tolerated over 12 weeks; liver enzymes and serum creatinine remained stable in both groups. BUN changed differently between groups (p = 0.007), decreasing slightly in Group A but increasing in Group B. FBG changed by −6.21 mg/dL in Group A and +22.25 mg/dL in Group B (between-group p = 0.014), whereas HbA1C changed by +0.23% in Group A and +0.42% in Group B, with no significant between-group difference (p = 0.230). OGTT glucose exposure increased within both groups (Group A: tAUC +12,821 and iAUC +12,209; Group B: tAUC +15,504 and iAUC +12,651), with no significant between-group difference. These findings indicate short-term tolerability but do not demonstrate improved dynamic glucose tolerance; the lower dose showed a more favorable glycemic trend than the higher dose in this small non-placebo pilot. However, this observation is hypothesis-generating and should not be interpreted as a clinical recommendation.
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