Benedryl or namely Diphenhydramine(the chemical name) can give you a feeling of euphoria. It is not safe to take in large amounts and should not be used in this manner. but if you are going to BE VERY CAREFUL! 25-50 mgs is the normal dose. if you take more than that you could go into respiratory or cardiac arrest.
Insulin deficiency (symptom description): For a medical symptom description of 'Insulin deficiency', the following symptom information may be relevant to the symptoms: Diabetes-like symptoms (type of symptom). However, note that other causes of the symptom 'Insulin deficiency' may be possible.
Low Blood Sugar Symptoms. A low blood sugar, also called hypoglycemia or an insulin reaction, is defined as a blood glucose level below 60 to 70 mg/dl. It is usually companied by one or more of the symptoms described below. Low blood sugars or insulin reactions can occur whenever insulin is used. Although less frequent, it can also occur with use of drugs that stimulate insulin production in Type 2 diabetes, such as Diabenese, Glyburide, Glipizide, and Starlix.