TESTOSTERIN™ is a unique supplement containing high doses of pantothenic acid and L-tyrosine. Pantothenic acid, also known as vitamin B5, is a water-soluble vitamin from the B complex. It plays a role in the synthesis of steroid hormones, vitamin D, and certain neurotransmitters. In addition, it contributes to healthy mental performance, energy-yielding metabolism, and the reduction of tiredness and fatigue. L-Tyrosine is a building block for proteins and a precursor to other important substances. It is an amino acid that the body can produce itself from phenylalanine, but does not always do so in sufficient quantities.