A method of utilizing the
chymotrypsin level of an individual as a measure of the success of
secretin, other neuropeptides, and peptides or
digestive enzyme administration to such individuals, and in particular, as a prognosticative of potential
secretin, other neuropeptides, peptides, and
digestive enzyme administration for persons having ADD, ADHD,
Autism and other PDD related disorders. In one aspect, a method for determining the
efficacy of
secretin, other neuropeptides, peptides, or digestive enzymes for the treatment of an individual diagnosed with a
pervasive developmental disorder (PDD) comprises obtaining a sample of
feces from an individual, determining a quantitative level of
chymotrypsin present in the sample, and correlating the quantitative level of
chymotrypsin determined to be present in the sample with the PDD to determine the
efficacy of treating the individual with secretin, other neuropeptides, peptides, or
digestive enzyme administration. In another aspect, a therapeutic method for treating an individual diagnosed with a PDD
pervasive developmental disorder comprises determining the
efficacy of secretin, other neuropeptides, peptides, and digestive
enzyme administration for the treatment of the
individual based on a measure of the individual's chymotrypsin level, and administering secretin, other neuropeptides, peptides, or digestive enzymes to the
individual based on the determination of the measure of the individual's chymotrypsin level.