Diabetes Mellitus and Insulin Therapy

Diabetes Mellitus

• Chronic disorder with abnormal carbohydrate metabolism
• Characterized by either insufficient insulin production (Type 1 DM) or insulin resistance (Type 2 DM)
• Long-term complications include macrovascular (heart disease, stroke) and microvascular (retinopathy, nephropathy, neuropathy) issues.

Insulin Therapy

• Mechanism of Action: Promotes glucose uptake by cells, stores glucose in the liver, and prevents fat and protein breakdown.
• Rapid-acting: (e.g., Lispro, Aspart, Glulisine): Onset 10-30 min, peak 0.5-3 hr, duration 3-6 hr.
• Short-acting: (e.g., Regular insulin): Onset 30-60 min, peak 1-5 hr, duration 6-10 hr.
• Intermediate-acting: (e.g., NPH insulin): Onset 1-2 hr, peak 6-14 hr, duration 16-24 hr.
• Long-acting: (e.g., Glargine, Detemir): Onset 1-2 hr, no peak, duration 24 hr or more.
• Ultra-long acting: (e.g., Degludec): Duration over 42 hours, no peak.
• Administered subcutaneously or intravenously (only regular insulin).
• Sites should be rotated to prevent lipohypertrophy.
• Side effects include hypoglycemia, weight gain, and allergic reactions.
• Management and dosage are individualized based on blood glucose monitoring.

Rule of 15

• Consume 15 grams of fast-acting carbohydrates (e.g., 4 glucose tablets, 4 ounces fruit juice, 1 tablespoon sugar/honey, 6-7 hard candies)
• Wait 15 minutes, and recheck blood glucose level.
• Repeat process if blood glucose is still low (below 70mg/dL or 3.9 mmol/L)
• After blood glucose returns to normal, eat a small snack with protein and complex carbohydrates to stabilize blood sugar.

Oral Antidiabetic Drugs (Type 2 DM)

• Biguanides (e.g., Metformin): Reduce glucose production by the liver, enhance insulin sensitivity.

• Benefits: No risk of hypoglycemia, weight loss.

• Side Effects: Gastrointestinal upset, lactic acidosis (rare but serious).

• Contraindications: Renal impairment, liver disease, alcohol abuse.

• Sulfonylureas (e.g., Glipizide, Glyburide, Glimepiride): Stimulate the pancreas to release more insulin. -Side Effects: Hypoglycemia, weight gain. -Drug Interactions: Alcohol, beta-blockers.

• Meglitinides (e.g., Repaglinide, Nateglinide): Similar to sulfonylureas, but shorter acting. -Administration: Take before meals to prevent postprandial hyperglycemia. -Side Effects: Hypoglycemia (less risk than sulfonylureas), weight gain.

• Thiazolidinediones (e.g., Pioglitazone, Rosiglitazone): Reduce insulin resistance by increasing glucose uptake in muscles and adipose tissue.

  -Side Effects: Fluid retention, heart failure, bladder cancer (pioglitazone), fractures in women. -Monitoring: Liver function tests, heart function

• Alpha-Glucosidase Inhibitors (e.g., Acarbose, Miglitol): Delay carbohydrate digestion and absorption in intestine, lowering postprandial glucose. -Side Effects: Flatulence, cramps, diarrhea, liver dysfunction (acarbose).

• DPP-4 Inhibitors (e.g., Sitagliptin, Saxagliptin, Linagliptin): Inhibit enzyme DPP-4, preventing breakdown of incretin hormones, which help regulate glucose levels.

   -Side Effects: Upper respiratory infections, pancreatitis, joint pain.
  

• SGLT-2 Inhibitors (e.g., Canagliflozin, Dapagliflozin, Empagliflozin): Increase glucose excretion through the urine by inhibiting glucose reabsorption in the kidneys.

  -Benefits: Weight loss, reduced blood pressure, cardiovascular benefits. -Side Effects: Genital infections, UTIs, dehydration, ketoacidosis.

• GLP-1 Receptor Agonists (e.g., Exenatide, Liraglutide, Dulaglutide): Mimic the incretin hormone GLP-1. -Administration: Subcutaneous injection -Side Effects: Nausea, vomiting, weight loss, pancreatitis.

• Amylin Mimetics (e.g., Pramlintide): Reduces postprandial glucose by slowing gastric emptying and suppressing glucagon secretion. -Administration: Subcutaneous injection, typically used in Type 1 and insulin-dependent Type 2 DM, -Side Effects: Hypoglycemia (especially with insulin), nausea

Hypoglycemia Management

• Mild: 15-20g of fast-acting carbohydrates
• Severe: Glucagon injection or IV dextrose for unconscious patients

Monitoring and Patient Education

• Self-monitoring of blood glucose
• Importance of lifestyle changes (diet, exercise)
• Recognize symptoms of hyperglycemia and hypoglycemia.
• Proper insulin injection technique and site rotation.