Humulin R Regular Insulin is a short-acting human insulin (rDNA origin) manufactured by Eli Lilly, available in a 10mL multi-dose vial at a concentration of 100 units/mL (1,000 units total per vial). It is used to improve glycemic control in adults and pediatric patients with diabetes mellitus by increasing insulin levels in the body, which lowers blood glucose. It belongs to the class of regular or short-acting insulins and is often used in combination with changes to diet and exercise.

Humulin R is a clear, colorless liquid with a water-like appearance. It is administered by subcutaneous injection (under the skin) approximately 30 minutes before a meal, or intravenously under medical supervision. Always use a U-100 insulin syringe when drawing from this vial. Recommended injection sites include the abdomen, buttocks, upper arms, and upper thighs; rotate injection sites to prevent lipodystrophy at any single site.

Unopened vials may be stored at room temperature up to 30°C (86°F) for up to 31 days, or refrigerated until the expiration date. Opened vials may be stored in a refrigerator or at room temperature up to 30°C (86°F) for up to 31 days. Do not freeze. Protect from direct light and heat. Do not use if the solution appears cloudy, thick, or discolored.