A therapeutic composition for the treatment of the symptoms of neurological and mental health disorders, such as Alzheimers, bipolar disorder, obsessive compulsive disorder, and oppositional defiant disorder, and the method for preparing the therapeutic agents is disclosed. The therapeutic agent is a stable pharmaceutical preparation containing, but not limited to, digestive/pancreatic enzymes. The therapeutic agent may be manufactured by a variety of encapsulation technologies. Delivery of the therapeutic agent may be made orally, through injection, by adherence of a medicated patch or other method. Further, a method of using fecal chymotrypsin level as an indicator of the presence of neurological and mental health disorders, such as Alzheimers, bipolar disorder, obsessive compulsive disorder, and oppositional defiant disorder, or the likelihood of an individual to develop these disorders is disclosed.