PurposeThe aim of this study was to investigate the efficacy and safety of a mixed extract of Trigonella foenum-graecum seed and Lespedeza cuneata (TFGL) for the treatment of testosterone deficiency syndrome (TDS).Materials and MethodsPatients were instructed to take a placebo or 200 mg TFGL capsule twice per day for 8 weeks. The primary efficacy variable was the change from baseline in the Aging Males' Symptoms scale (AMS), as well as levels of serum total and free testosterone. Secondary efficacy measurements included changes from baseline in the number of ‘yes’ answers on the Androgen Deficiency in the Aging Male (ADAM) questionnaire, levels of serum total cholesterol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglyceride, all domain scores of the International Index of Erectile Function (IIEF), perceived stress scale-10 (PSS-10), as well as changes in body composition.ResultsThe TFGL group exhibited a significant improvement in the AMS scores at 8 weeks, total testosterone at 8 weeks, and free testosterone at 4 and 8 weeks. At 4 weeks, 25% of the TFGL group changed to negative in terms of ADAM scores and 34.1% of the TFGL group had negative scores at the end of the study. The TFGL group exhibited a significant improvement in total cholesterol, HDL-C, LDL-C, triglyceride, IIEF scores, and PSS-10 scores at 8 weeks.ConclusionsThe mixed extract of TFGL resulted in significant improvements in symptoms of TDS, as measured by the AMS, ADAM, PSS-10 and testosterone levels.