Insulin Isophane 70% + Human insulin 30%
Overview
Insulin Isophane 70% + Human Insulin 30% is a biphasic premixed insulin formulation that combines intermediate-acting insulin isophane with short-acting soluble human insulin in a fixed 70:30 ratio. The soluble human insulin component provides early glucose-lowering action to control postprandial blood sugar rises, while the insulin isophane component delivers a prolonged insulin effect to support basal glycemic control over several hours. This dual-action profile allows coordinated management of both mealtime and background insulin requirements using a single injection. Following subcutaneous administration, the formulation enhances peripheral glucose uptake and suppresses hepatic glucose production, addressing core metabolic abnormalities in diabetes mellitus. Premixed insulin regimens such as this are widely used in routine diabetes care, particularly in patients who benefit from simplified dosing schedules and predictable insulin action profiles as part of long-term glycemic management.
Background and Date of Approval
Premixed human insulin formulations combining insulin isophane and soluble human insulin were developed to simplify insulin therapy while maintaining effective glycemic control. One of the earliest and most widely used formulations, Humulin 70/30, received approval from the United States Food and Drug Administration on 25 April 1989 for improving glycemic control in patients with diabetes mellitus. Similar 70/30 biphasic human insulin products have since been approved and used globally under various brand names. These approvals were supported by clinical evidence demonstrating reliable postprandial and basal glucose control with established safety profiles when used according to recommended dosing and monitoring practices.
Uses
Insulin Isophane 70% + Human Insulin 30% is indicated for the treatment of patients with type 1 diabetes mellitus and for patients with type 2 diabetes mellitus who require insulin therapy to achieve adequate glycemic control. It is particularly suitable for individuals who require both prandial insulin coverage and intermediate basal insulin support in a fixed combination. The formulation may be administered once or twice daily before meals, depending on individual glycemic patterns, lifestyle, and clinical requirements. It is used as part of a comprehensive diabetes management plan that includes dietary regulation, physical activity, and regular blood glucose monitoring.
Administration
This premixed insulin is administered by subcutaneous injection into the abdomen, thigh, buttocks, or upper arm. Injection sites should be rotated regularly to minimize the risk of lipodystrophy and localized skin reactions. The suspension must be gently resuspended before administration to ensure uniform distribution of insulin components. It is typically injected approximately 30 to 45 minutes before meals to align the short-acting insulin effect with postprandial glucose excursions. Dosage is individualized based on patient body weight, insulin sensitivity, prior insulin use, and glycemic targets, with adjustments guided by blood glucose monitoring results.
Side Effects
The most common side effect associated with Insulin Isophane 70% + Human Insulin 30% is hypoglycemia, which may present with symptoms such as sweating, tremors, hunger, dizziness, headache, or confusion. Injection site reactions including redness, swelling, itching, or discomfort may occur. Weight gain can be observed as glycemic control improves. These effects vary between patients and are generally manageable with appropriate dose adjustment and clinical supervision.
Warnings
Serious adverse events include severe hypoglycemia, which may lead to seizures, loss of consciousness, or death if not promptly treated. Hypokalemia may occur due to insulin-mediated intracellular potassium shifts and can result in cardiac rhythm disturbances. Allergic reactions, including localized or systemic hypersensitivity, have been reported. Fluid retention and worsening of heart failure may occur when insulin is used in combination with certain antidiabetic agents. This formulation should not be used during episodes of hypoglycemia, and careful patient education is essential to minimize risk.
Precautions
Baseline assessment of glycemic control, renal function, and hepatic function is recommended prior to initiating therapy. Changes in diet, physical activity, body weight, stress levels, or intercurrent illness can significantly affect insulin requirements. Concomitant medications such as beta-blockers, corticosteroids, diuretics, and other glucose-lowering agents may alter insulin response or mask symptoms of hypoglycemia. Regular blood glucose monitoring is essential to guide dose adjustments and ensure safe long-term use.
Expert Tips
Patient selection should consider lifestyle regularity, meal timing, and ability to recognize hypoglycemia. Proper education on injection technique, site rotation, and correct resuspension of the premixed insulin is critical for consistent dosing. Dose titration should be gradual and based on structured blood glucose monitoring data. Patients should be advised to carry fast-acting carbohydrates for immediate management of hypoglycemic episodes. Ongoing collaboration between prescribers, pharmacists, and diabetes educators supports adherence and optimizes long-term outcomes.