Usage
- Human insulin + Insulin Isophane is prescribed for the treatment of Type 1 and Type 2 Diabetes Mellitus. This combination provides both rapid and intermediate-acting insulin to manage blood glucose levels effectively.
- Pharmacological classification: Antidiabetic Agent, Insulin.
- Mechanism of action: This combination works by mimicking the action of endogenous insulin. It binds to insulin receptors on cell membranes, facilitating glucose uptake from the bloodstream into cells for energy production or storage. It also inhibits hepatic glucose production.
Alternate Names
- While “Human Insulin + Insulin Isophane” is the standard generic name, it’s often referred to as a “premixed insulin.” The 70/30 mix is a common formulation (70% isophane insulin and 30% regular human insulin).
- Brand Names: Humulin 70/30, Novolin 70/30.
How It Works
- Pharmacodynamics: The combination lowers blood glucose by increasing glucose transport into skeletal muscle and fat cells, and by inhibiting hepatic glucose production.
- Pharmacokinetics: Regular insulin (the short-acting component) is absorbed rapidly from the subcutaneous injection site, with an onset of action within 30 minutes, peaking in 2-4 hours, and lasting 5-8 hours. Isophane insulin (the intermediate-acting component) has an onset of action within 1-2 hours, peaks in 4-12 hours, and lasts for 14-24 hours. The combination provides a dual-action profile.
- Mode of Action: Binds to insulin receptors, a transmembrane receptor tyrosine kinase. Receptor binding triggers intracellular signaling cascades, leading to GLUT4 translocation to the cell surface, facilitating glucose transport into cells.
- Elimination: Primarily through hepatic metabolism, with a small fraction of renal excretion.
Dosage
Standard Dosage
Adults:
- The initial dose is usually between 0.5 and 1 unit/kg/day, split into two doses. Non-obese individuals might require 0.4-0.6 units/kg/day, while obese individuals could need 0.8-1.2 units/kg/day.
- Dosing frequency is typically twice daily (before breakfast and before the evening meal), although adjustments might be needed.
Children:
- Pediatric dosing is also weight-based, usually starting at 0.5 U/kg/day, with careful monitoring and adjustments based on blood glucose levels.
Special Cases:
- Elderly Patients – May require lower initial doses due to age-related changes in insulin sensitivity and renal function.
- Patients with Renal Impairment – Dosage adjustments may be needed based on the degree of impairment.
- Patients with Hepatic Dysfunction – Caution is advised, and lower doses may be considered initially.
- Patients with Comorbid Conditions – Dosage adjustments might be necessary based on coexisting medical conditions, such as cardiovascular disease.
Clinical Use Cases
This medication is primarily for chronic management of diabetes and isn’t specifically indicated for acute conditions like intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations. Short-acting insulins or intravenous glucose solutions are often utilized in these contexts.
Dosage Adjustments
- Dosage modifications should be individualized based on blood glucose monitoring, patient response, and any concurrent illnesses or medications.
Side Effects
Common Side Effects
- Hypoglycemia (low blood sugar), injection site reactions (redness, swelling, itching), weight gain.
Rare but Serious Side Effects
- Severe hypoglycemia (loss of consciousness, seizures), allergic reactions (rash, hives, difficulty breathing).
Long-Term Effects
- Lipodystrophy (changes in fat tissue at the injection site).
Adverse Drug Reactions (ADR)
- Anaphylaxis (a severe, life-threatening allergic reaction).
Contraindications
- Hypoglycemia.
- Hypersensitivity to human insulin or any component of the formulation.
Drug Interactions
- Certain medications can affect insulin sensitivity, including corticosteroids, thiazide diuretics, and beta-blockers.
Pregnancy and Breastfeeding
- Generally considered safe during pregnancy and breastfeeding, with dose adjustments as needed based on blood glucose monitoring. Insulin does not cross the placenta or enter breast milk.
Drug Profile Summary
- Mechanism of Action: Mimics endogenous insulin action by promoting glucose uptake into cells and inhibiting hepatic glucose output.
- Side Effects: Hypoglycemia, injection site reactions, weight gain.
- Contraindications: Hypoglycemia, hypersensitivity to insulin.
- Drug Interactions: Corticosteroids, thiazide diuretics, beta-blockers.
- Pregnancy & Breastfeeding: Generally safe.
- Dosage: 0.5-1 unit/kg/day initially, adjusted based on blood glucose monitoring.
- Monitoring Parameters: Blood glucose levels (regularly).
Popular Combinations
- Often used in conjunction with other oral antidiabetic agents (like metformin) or other types of insulin.
Precautions
- General Precautions: Proper injection technique, blood glucose monitoring.
- Specific Populations: Dosage adjustments for elderly, renally/hepatically impaired patients. Close monitoring during pregnancy and breastfeeding.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Human insulin + Insulin Isophane?
A: The starting dose is typically 0.5-1 unit/kg/day, split into two doses. Adjustments are made based on individual needs and blood glucose levels.
Q2: How is Human insulin + Insulin Isophane administered?
A: Subcutaneously, usually twice daily, before meals.
Q3: What are the common side effects?
A: Hypoglycemia, injection site reactions, and weight gain.
Q4: What should I do if a patient experiences hypoglycemia?
A: If mild, administer oral glucose (like fruit juice or glucose tablets). If severe, glucagon or intravenous glucose may be needed.
Q5: Can this combination be used during pregnancy?
A: Yes, but close monitoring of blood glucose is necessary, and dosage adjustments might be needed.
Q6: How does renal impairment affect dosing?
A: Reduced renal function may necessitate a lower dose due to decreased clearance.
Q7: Does this insulin mix interact with other medications?
A: Yes, several drugs can influence insulin’s action, including corticosteroids.
Q8: Are there any long-term complications?
A: Lipodystrophy can occur at the injection site with repeated injections in the same area. Rotate injection sites regularly.
Q9: What is the difference between Human Insulin + Insulin Isophane and other insulins?
A: This premixed combination offers both rapid and intermediate action, helping manage blood glucose levels throughout the day with fewer injections compared to using separate rapid and intermediate-acting insulins.
