E.E.S. 400 Interactions Should I avoid certain foods while taking E.E.S. 400?e-e-s-400 may interact with the following foods: Very important: A change in your diet, medicine, or dosage may be necessary. Promptly consult your doctor or pharmacist. TAKE NON-ENTERIC COATED FORM ON EMPTY STOMACH. AVOID GRAPEFRUIT UNLESS MD INSTRUCTS OTHERWISE.