This invention relates to the use of ADNF polypeptides in the treatment of neurotoxicity induced by chemical agents or by disease processes. The ADNF polypeptides include ADNF I and ADNF III (also referred to as ADNP) polypeptides, analogs, subsequences such as NAP and SAL, and D-amino acid versions (either wholly D-amino acid peptides or mixed D- and L-amino acid peptides), and combinations thereof which contain their respective active core sites.