Natural Factors L-Tyrosine - 500 mg - A free form amino acid that helps transmit nerve impulses to the brain by increasing the production of neurotransmitters that carry messages from one nerve cell to the next. The presence of Tyrosine in proper quantities can help decrease irritability, agitation and the sensation of being overwhelmed. Clinical studies have also shown Tyrosine to be beneficial in reducing fatigue and in helping to reduce feelings of anxiety and low libido. Tyrosine can also be helpful in reducing feelings of irritability, anxiety, weepiness and agitation associated with PMS.