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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Insulin of choice for the treatment of diabetes mellitus is:
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The correct answer is  (Ref: Katzung 14th ed. P 753)Regular insulin is a short-acting, soluble crystalline zinc insulinHypoglycemic effect appears within 30 minutes after subcutaneous injection, peaks at about 2 hours, and lasts for 5-7 hours.For very insulin-resistant subjects who would otherwise require large volumes of insulin solution, a U500 preparation of human regular insulin is available both in a vial form and a disposable penIV infusion: used in treatment of diabetic ketoacidosis