Insulin Aspart Protamine

Usage

• Insulin Aspart Protamine is prescribed for Type 1 and Type 2 diabetes mellitus to control hyperglycemia.
• Pharmacological Classification: Rapid-acting/Intermediate-acting Insulin, Antidiabetic Agent.
• Mechanism of Action: Insulin Aspart Protamine is a combination of insulin aspart (rapid-acting) and insulin aspart protamine (intermediate-acting). It mimics endogenous insulin, facilitating glucose uptake by muscle and fat cells and suppressing hepatic glucose production.

Alternate Names

• Insulin aspart protamine/insulin aspart
• Brand Names: NovoLog Mix 70/30, NovoMix 30

How It Works

• Pharmacodynamics: Lowers blood glucose by binding to insulin receptors, promoting glucose transport into cells and inhibiting hepatic glucose output. The 30/70 mix provides both rapid and sustained glucose control.
• Pharmacokinetics:
  • Absorption: Subcutaneous absorption is faster for the insulin aspart component, providing a rapid onset of action, while the protamine-bound aspart is absorbed more slowly, giving an intermediate duration of action.
  • Metabolism: Primarily metabolized in the liver and kidneys by insulin-degrading enzymes.
  • Elimination: Excreted by the kidneys.
• Mode of Action: Binds to insulin receptors, triggering intracellular signaling cascades that lead to increased glucose uptake and utilization.
• Receptor Binding: Binds specifically to insulin receptors. The binding triggers tyrosine kinase activity, activating pathways responsible for glucose transport and glycogen synthesis.
• Elimination Pathways: Primarily renal and hepatic.

Dosage

Standard Dosage

Adults:

• Type 1 Diabetes: 0.5-1.0 units/kg/day, divided into two doses. Adjust based on individual needs.
• Type 2 Diabetes: Initial dose: 6 units twice daily or 12 units once daily. Titrate based on individual glycemic response.

Children:

• 10 years and older: Similar to adult dosing.
• 6-9 years: Limited clinical experience; use with caution.
• Under 6 years: Not recommended.

Special Cases:

• Elderly Patients: Initiate at lower doses and titrate cautiously due to increased risk of hypoglycemia.
• Patients with Renal Impairment: Dosage adjustment is necessary. Monitor closely.
• Patients with Hepatic Dysfunction: Dosage adjustment is necessary. Monitor closely.
• Patients with Comorbid Conditions: Adjust dosage based on individual needs and metabolic status.

Clinical Use Cases

Insulin Aspart Protamine is typically not used in clinical settings such as intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations. Rapid-acting insulin or intravenous glucose solutions are preferred in these scenarios for tighter glycemic control.

Dosage Adjustments

Adjustments are required based on patient factors like physical activity, meal patterns, renal/hepatic function, and acute illness. Close monitoring of blood glucose is crucial.

Side Effects

Common Side Effects

• Hypoglycemia
• Injection site reactions (redness, swelling, itching)
• Weight gain

Rare but Serious Side Effects

• Severe hypoglycemia
• Anaphylaxis
• Hypokalemia

Long-Term Effects

• Lipodystrophy

Adverse Drug Reactions (ADR)

• Severe hypoglycemia requiring assistance
• Angioedema

Contraindications

• Hypoglycemia
• Hypersensitivity to insulin aspart, protamine, or excipients.

Drug Interactions

• Medications affecting glucose metabolism (e.g., oral antidiabetics, corticosteroids)
• ACE inhibitors
• Beta-blockers
• Alcohol

Pregnancy and Breastfeeding

• Pregnancy Safety Category: B
• Fetal Risks: Potential for fetal hypoglycemia; monitor carefully.
• Breastfeeding: Insulin aspart does transfer into breast milk, but poses minimal risk to the infant. Dosage adjustments may be necessary.

Drug Profile Summary

• Mechanism of Action: Enhances glucose uptake and suppresses hepatic glucose output.
• Side Effects: Hypoglycemia, injection site reactions, weight gain.
• Contraindications: Hypoglycemia, hypersensitivity.
• Drug Interactions: Medications altering glucose metabolism.
• Pregnancy & Breastfeeding: Generally safe; monitor blood glucose.
• Dosage: Individualized based on patient need.
• Monitoring Parameters: Blood glucose levels, potassium levels.

Popular Combinations

Often combined with other oral antidiabetic agents or GLP-1 receptor agonists to achieve glycemic control.

Precautions

• Monitor blood glucose regularly.
• Rotate injection sites to avoid lipodystrophy.
• Educate patients on recognizing and treating hypoglycemia.
• Patients with renal or hepatic impairment require careful monitoring and dosage adjustments.
• Alcohol can potentiate hypoglycemia.

FAQs (Frequently Asked Questions)

Q1: What is the recommended dosage for Insulin Aspart Protamine?

A: The dosage is individualized. Adults typically start with 0.5-1 unit/kg/day, divided into two doses before meals. Type 2 diabetics may start with 6 units twice daily or 12 units once daily.

Q2: When should this insulin be administered?

A: Immediately before or soon after a meal.

Q3: What are the signs of hypoglycemia?

A: Chills, cold sweats, blurred vision, dizziness, drowsiness, shaking, rapid heartbeat, weakness, headache, fainting, tingling in hands/feet, and hunger.

Q4: What should a patient do if they experience hypoglycemia?

A: Consume a fast-acting carbohydrate source like glucose tablets, juice, or candy.

Q5: Can Insulin Aspart Protamine be used during pregnancy?

A: Yes, but close monitoring of blood glucose is crucial. Dosage adjustments are often needed during pregnancy.

Q6: Is it safe to breastfeed while using this medication?

A: Generally yes. Insulin aspart is present in breast milk, but at very low levels. Monitor the infant and adjust dosage as needed.

Q7: What are the long-term side effects of Insulin Aspart Protamine?

A: Lipodystrophy can occur at the injection site with repeated injections. Rotate injection sites to minimize this risk.

Q8: Are there any drug interactions I should be aware of?

A: Yes, medications like corticosteroids and oral antidiabetics can affect blood glucose levels. Consult with the patient’s physician to assess potential drug interactions.

Q9: What are the storage recommendations for Insulin Aspart Protamine?

A: Unopened vials/pens should be refrigerated. Once in use, store at room temperature and discard after 28 days. Do not freeze.

Q10: How should patients mix the insulin before injection?

A: Gently roll the vial/pen 10 times between palms before each injection to ensure proper mixing of the suspension. Do not shake vigorously.