Advanced Therapeutics Huperzine Rx-BrainÂ®, from Nature's Plus, is a precisely calibrated nutritional formulation born from leading-edge scientific studies and clinical evaluation. Each tablet provides pure Huperzine-A, the active neuronutrient found in the rare species of Chinese moss, Huperzia serrata. Huperzine Rx-BrainÂ® source ingredient, club moss, is hand-picked by trained horticultural specialists who select only the best plant specimens for consistent maximum potency. Huperzine Rx-BrainÂ® is a neuronutrient whose active ingredient is verified for purity and potency at each stage of production, including: extraction, manufacture, and tableting. Rx-BrainÂ® is a unique specialty formula designed for any individual concerned with promoting optimal brain function.