Section 4D. A group health maintenance contract shall provide coverage for nonprescription enteral formulas for home use for which a physician has issued a written order and which are medically necessary for the treatment of malabsorption caused by Crohn’s disease, ulcerative colitis, gastroesophageal reflux, gastrointestinal motility, chronic intestinal pseudo-obstruction, and inherited diseases of amino acids and organic acids. Coverage for inherited diseases of amino acids and organic acids shall include food products modified to be low protein in an amount not to exceed two thousand five hundred dollars annually for any insured individual.