Abstract: In animals including humans, the symptoms of non-anaphylactic disease states wherein the disease victim's humoral and/or cell-mediated immunological response is involved in disease pathology are alleviated upon administration of compositions comprising mixtures of histamine and one or more immunogenic substances participative in the humoral or cell-mediated pathogenic response. In preferred embodiments, the compositions are administered in essentially minute, "neutralizing" doses. Illustratively, significant relief of symptoms of multiple sclerosis is achieved through parenteral (e.g., subcutaneous of sublingual) administration of mixtures of histamine and measles virus immunogen. For a majority of patients, from about 8.8.times.10.sup.-6 to 5.5.times.10.sup.-3 mg of histamine phosphate will provide an effective quantity of histamine to a unit dose of the mixture. Likewise, a unit dose of the mixture will contain from about 2.times.10.sup.-3 to about 4.times.10.sup.