A biphasic isophane insulin injection, also known as biphasic human insulin or 50/50 mixed insulin. It is a sterile, white, and cloudy suspension containing 50% intermediate-acting Insulin Isophane (NPH) and 50% short-acting Human Insulin (Soluble/Regular Insulin) in a neutral phosphate buffer. This premixed formulation is designed to provide both prandial (mealtime) and basal (background) insulin coverage in a single injection, simplifying the regimen for patients with diabetes mellitus. It is a critical component of diabetes management in the Indian healthcare setting due to its cost-effectiveness and ease of use.
Adult: Highly individualized. Typically administered once or twice daily (before breakfast and/or before dinner). Starting dose in insulin-naïve patients: 0.2-0.4 units/kg/day, divided. Often given 15-30 minutes before a major meal. Dose adjusted based on self-monitored blood glucose (SMBG) patterns.
Note: For subcutaneous use ONLY. Inject into abdominal wall, thigh, buttocks, or upper arm. Rotate sites within a region to prevent lipodystrophy. Use a U-100 insulin syringe or pen device. Before use, resuspend gently by rolling between palms until uniformly cloudy. Do not use if clear droplets remain or if clumping/frosting occurs. Do not mix with other insulins in the same syringe (as it is already premixed). Administer 15-30 minutes before a meal.
Insulin is the principal hormone required for proper glucose utilization. It regulates carbohydrate, lipid, and protein metabolism by promoting cellular uptake of glucose (especially in muscle and adipose tissue), inhibiting hepatic glucose production (gluconeogenesis and glycogenolysis), and promoting glycogen, lipid, and protein synthesis. The soluble insulin component acts rapidly to control postprandial glucose rises, while the isophane (NPH) component provides a prolonged action to manage interprandial and basal glucose levels.
Pregnancy: Pregnancy Category B. Insulin is the drug of choice for diabetes in pregnancy. Requirements may decrease in first trimester and increase significantly in second/third trimesters. Close monitoring (fasting and postprandial glucose, HbA1c) and frequent dose adjustments are mandatory. This premixed insulin may be used, but basal-bolus regimens offer more flexibility.
Driving: Hypoglycemia can impair cognitive and motor functions, making driving dangerous. Patients must check blood glucose before driving and regularly during long journeys. Always carry fast-acting carbohydrates (glucose tablets) in the vehicle.
| Oral Hypoglycemic Agents (Sulfonylureas, Meglitinides) | Additive hypoglycemic effect, increased risk of hypoglycemia | Major |
| Corticosteroids (e.g., Prednisolone, Dexamethasone) | Antagonize insulin effect, cause hyperglycemia, increased insulin requirement | Major |
| Beta-blockers (e.g., Propranolol) | May mask tachycardia of hypoglycemia, potentiate hypoglycemia, impair recovery | Moderate |
| Thiazide Diuretics (e.g., Hydrochlorothiazide) | Cause hyperglycemia, increased insulin requirement | Moderate |
| Alcohol | Potentiates hypoglycemic effect, risk of delayed hypoglycemia, especially overnight | Major |
| ACE Inhibitors (e.g., Ramipril), MAOIs, Pentamidine | May increase hypoglycemic effect | Moderate |
| Thyroid hormones, Somatropin, Danazol | May increase insulin requirement | Moderate |
Same composition (Insulin Isophane/NPH (50%) + Human Insulin/Soluble Insulin (50%)), different brands: