Oral Hypoglycemic Drugs Classification Question And Answers

Insulin And Oral Hypoglycaemics Important Notes

1. Insulin And Oral Hypoglycaemics Classification of Insulins

• Conventional
  • Short-acting – regular insulin, prompt insulin zinc suspension
  • Intermediate-acting – insulin zinc suspension, neutral protamine (Isophane)
  • Long-acting – extended insulin zinc suspension, protamine zinc suspension
• A highly purified insulin preparation
  • Single peak insulin
  • Monocomponent insulin

2. Insulin And Oral Hypoglycaemics Oral hypoglycaemic drugs

• Sulphonylureas
  • First generation – tolbutamide, chlorpropamide
  • Second generation – glibenclamide, glopizide
• Biguanides
  • Metformin, phenformin
• Meglitinides
  • Repaglinide
• Alpha glycosidase inhibitor – acarbose

3. Insulin And Oral Hypoglycaemics Sulphonylureas

• Stimulators of beta cells
• Reduces blood glucose in normal subjects and type 2 diabetes
• Mode of action
  • Brings the release of insulin by activating receptors on beta cells of the pancreas
  • Reduces glucagon secretion
  • Increases insulin receptors on target cells
  • Inhibits gluconeogenesis in the liver

4. Insulin And Oral Hypoglycaemics Metformin

• It is a biguanide, an oral hypoglycaemic drug
• Contraindications
  • Hypotension
  • CVS diseases
  • Respiratory diseases
  • Hepatic and renal diseases
  • Alcoholics
• Action
  • Suppresses hepatic gluconeogenesis and glucose output from the liver
  • Interferes with mitochondrial respiratory chain
• Not metabolized at all
• Excreted unchanged in the urine

5. Insulin And Oral Hypoglycaemics Chlorpropamide

• Long-acting hypoglycaemic
• Reduces urine volume in diabetes insipidus
• Sensitizes kidney to ADH action

Read And Learn More: Pharmacology Question and Answers

Insulin And Oral Hypoglycaemics Long Essays

Question 1. Classify antidiabetic drugs and write about oral antidiabetic drugs.
Answer:

Anti-diabetic drugs:

• These drugs used lower blood glucose levels.

Anti-diabetic drugs Classification:

1. Insulin.

• Ultra short-acting or rapid-acting.
  • Insulin lispro, insulin aspart, insulin glulisine.
• Short-acting.
  • Regular insulin.
• Intermediate acting.
  • Insulin zinc suspension, neutral protamine hagedorn.
• Long-acting.
  • Protamine zinc insulin, insulin glargine.

2. Oral hypoglycaemics.

• Sulfonylureas.
  • First generation – tolbutamide, chlorpropamide.
  • Second generation – Glibenclamide, Glipizide.
• Biguanide – metformin.
• Meglitinide or phenylalanine analogues.
  • Repaglinide, Nateglinide.
• Thiazolidin editions.
  • Rosiglitazone, pioglitazone.
• Alpha-glucosidase inhibitors.
  • Acarbose, miglitol.
• Dipeptidyl peptidase – 4 inhibitor.
  • Sitagliptin, vildagliptin.

1. Anti-diabetic drugs Sulfonylureas:

• They were the first oral hypoglycaemic drugs.

Sulfonylureas Mechanism of action:

Sulfonylureas Uses:

• Used in patients with type II diabetes mellitus

Sulfonylureas Adverse effects:

• Hypoglycaemia.
• Nausea, vomiting, diarrhoea, headache, weight gain, paraesthesia, weight gain.
• Hypersensitivity reactions.

2. Anti-diabetic drugs Biguanides:

Biguanides Actions:

• Inhibit hepatic gluconeogenesis.
• Enhances insulin-mediated glucose disposal in muscle and fat
• Retards intestinal absorption of glucose.
• Promotes peripheral utilization of glucose

BiguanidesUse:

• Used in obese patients with type II diabetes mellitus.

3. Anti-diabetic drugs Meglitinide Analogues:

Meglitinide Analogues Mechanism:

Meglitinide Analogues Uses:

• Used in type 2 DM either alone or with metformin.

4. Anti-diabetic drugs Thiazolidinediones:

• They are selective agonists for the receptor nuclear peroxisome proliferator-activated receptor gamma.

Thiazolidinediones Uses:

• Type; 2 diabetes mellitus.
• Used to supplement sulfonylureas or metformin and in case of insulin resistance.

5. Anti-diabetic drugs Alpha-glucosidase inhibitors:

• Acarbose is one of the alpha-glucosidase inhibitors.
• It slows down digestion and absorption of polysaccharides and glucose.
• As an adjuvant to diet in obese diabetics.

Question 2. Describe the different preparations of insulin. Add a note on their merits and demerits.
Answer:

Insulin preparations:

• Insulin preparations differ in their source and duration of action.

1. Insulin preparations Conventional insulins:

• Rapid-acting.
  • Insulin lispro, insulin aspart, insulin glulisine.
• Short during.
  • Regular insulin.
• Intermediate acting.
  • Insulin zinc preparation, neutral protamins hatedom.
• Long-acting.
  • Protamine zinc insulin.

Conventional insulins Advantages/Mertis:

• Rapid onset
• Longer duration of action.

Conventional insulins Disadvantages/Demerits:

• Allergic.
• Not very stable
• Degraded in GIT, so not given orally.
• Antigenic.

2. Insulin preparations Highly purified insulins:

• Single peak insulin – regular, lente.
• Monocomponent insulin – regular, lente.

Highly purified insulins Advantages:

• Purified, thus contamination is negligible.
• Less antigenic.
• More stable.
• Lesser chances of resistance.
• Lesser chances of lipodystrophy.

Highly purified insulins Disadvantages:

• Expensive.

3. Insulin preparations Human insulin:

• Produced by recombinant DNA technology
• They are regular, lente, and isophane.

Human insulin Advantages:

• Less antigenic.
• So less allergic reactions.
• Less injection site lipodystrophy.

Human insulin Disadvantages:

• Expensive

4. Insulin preparations Insulin analogues:

• Synthesized by genetic engineering.
• They include insulin lispro, insulin aspart, insulin glargine, insulin glulisine, and insulin detemir.

Insulin analogues Advantages:

• Rapid absorption.
• Can be given 10 minutes before food.
• Less hypoglycaemia.
• Favourable pharmacokinetics.
• Better blood glucose control.
• Greater stability

Insulin analogues Disadvantages:

• Expensive preparation.

Question 3. Discuss Insulin pharmacological actions and adverse effects.
Answer:

Insulin Pharmacological Actions:

1. Carbohydrate metabolism.

• Insulin decreases blood glucose levels by
  • Increasing glucose uptake and glycogen synthesis.
  • Inhibits glycogenolysis and glucose output
  • Inhibits gluconeogenesis.
  • Facilitates glucose transport across the cell membrane
  • Alters activity of enzymes involved in metabolism.

2. Protein metabolism.

• Facilitates protein synthesis.
• Inhibits protein breakdown.
• Thus, has an anabolic effect

3. Lipid metabolism.

• Promotes synthesis of triglycerides.
• Inhibits lipolysis.

4. Insulin increases potassium entry into cells and decreases urea output from the liver.

Insulin Adverse effects:

1. Hypoglycaemia.

• Most common side effect.
• Occurs due to large doses, improper time of administration, missing a meal, and vigorous exercise.
• Prolonged hypoglycaemia may cause permanent brain damage.

2. Local reactions.

• Swelling, erythema and stinging at the site of injection.
• Localized lipodystrophy.

3. Allergy.

• Occurs due to contaminating proteins.
• Utricaria, angioedema and anaphylaxis occur.

4. Insulin resistance.

• Develops when insulin requirement is increased.

Question 4. Write the mechanism of action and therapeutic uses of insulin.
Answer:

Insulin:

Insulin is a hormone that is synthesized in the beta cells of pancreatic islets.

Insulin Mechanism of action:

Insulin Uses:

• In juvenile diabetes.
• When diabetes is not controlled by diet or exercise.
• Underweight patients.
• Failure of oral hypoglycaemic drugs.
• The stress of surgery, infections, trauma, pregnancy and labour.
• Complications of diabetes – diabetic coma, ketoacidosis, gangrene of extremities.

Question 5. Write the mechanism of action, uses and adverse effects of sulfonylureas.
Answer:

Sulfonylureas:

• They were the first oral hypoglycaemic drug to be introduced.

Sulfonylureas Mechanism of action:

Sulfonylureas Uses:

• Maturity onset diabetes
• Insulin resistant diabetes
• Diabetes insipidus.

Sulfonylureas Adverse effects:

• Hypoglycaemia.
• Nausea, vomiting, diarrhoea, constipation.
• Headache, paresthesia.
• Weight gain.
• Hypersensitivity – rashes, photosensitivity, purpura.
• Agranulocytosis, transient leukopenia.

Question 6. Mention the hormones secreted by the pancreas. What is diabetic coma? What are the principles of treatment?
Answer:

Hormones secreted by the pancreas are:

1. Hormones secreted by the pancreas Insulin.

• It is a hypoglycaemic hormone.
• Synthesized by p cells of pancreatic islets.
• It is two chain polypeptide having 51 amino acids.
• It facilitates glucose transport and inhibits glycol- analysis, and gluconeogenesis.
• Thus lowering blood glucose levels.

2. Hormones secreted by the pancreas Glucagon.

• It is a hyperglycaemic hormone.
• Secreted by cells of pancreatic islets.
• It enhances glycogenolysis and gluconeogenesis.
• Thus increasing blood glucose levels.

Glucagon Diabetic coma:

• Severe hyperglycaemia and glycosuria result in severe dehydration and increased plasma osmolarity leading to coma.
• Seen in insulin-dependent diabetes mellitus.

Glucagon Symptoms:

• Hyperglycaemia.
• Acidosis
• Hyperventilation
• Dehydration
• Hypotension
• Shock
• Impaired consciousness.

Glucagon Management:

1. Correction of hyperglycaemia.

• Intravenous regular insulin 0.1 U/kG bolus followed by 0.1 U/kg/hour by continuous IV infusion till patient recovers.

2. Correction of dehydration.

• IV fluids – normal saline IV1 litre/hour.

3. Correction of acidosis,

• Use of sodium bicarbonate.

4. Correction of hypokalemia.

• By IV KC1 infusion.

5. Supportive treatment – done by use of antibiotics.

Insulin And Oral Hypoglycaemics Short Essays

Question 1. Sulfonylurea.
Answer:

Sulfonylurea was the first oral hypoglycaemic drug to be introduced.

Sulfonylurea Classification:

1. First generation – Tolbutamide, chlorpropamide

2. Second generation – Glibenclamide, glipizide, Gli- clazide, Glimepride.

Question 2. Oral antidiabetic drugs.
Answer:

Oral antidiabetic drugs are drugs that lower blood glucose levels and are effective orally.

Oral antidiabetic drugs Classification:

1. Sulfonylureas.

• First generation – Tolbutamide, chlorpropamide.
• Second generation – Glibenclamide, glipizide.

2. Biguanide – metformin.

3. Meglitinide, phenylalanine analgues.

• Repaglinide, nateglinide.

4. Thiazolidinediones.

• Rosiglitazone, pioglitazone.

5. Alpha-glucosidase inhibitors.

• Acarbose, miglitol.

6. Dipeptidyl peptidase – 4 inhibitor.

• Sitaglipitin, vildagliptin.

Oral antidiabetic drugs uses:

Question 3. Insulin and sulphonylureas.
Answer:

Question 4. Advantages of newer insulin.
Answer:

Newer insulins are derived from the human pancreas.

• Hence, the risk of antigen-antibody reactions is avoided.
• They are highly purified preparations.
• Can be used in insulin resistance diabetes
• Can be used during pregnancy without teratogenicity.
• Can be used in case of injection site lipodystrophy caused by conventional preparation.

Question 5. Give reasons – glibenclamide is not useful in treating childhood diabetes mellitus.
Answer:

Glibenclamide is a second-generation sulphonylurea.

• Sulphonylurea causes the release of insulin from the pancreas.
• They act on receptors present on the pancreatic beta cell membrane.
• Causes depolarization by reducing the conductance of ATP-sensitive K+ channels.
• This enhances Ca²⁺ influx degeneration and insulin resistance.
• They cannot cause hypoglycaemia in pancreatic-atomized animals or in type I diabetes mellitus.
• Since type I diabetes occurs in children glibenclamide cannot be used to treat it.

Question 6. Compare and contrast conventional insulin with newer insulin.
Answer:

Question 7. Compare and contrast sulphonylurea and biguanides
Answer:

Question 8. Biguanides.
Answer:

• It is an oral hypoglycaemic drug
• It is not metabolized at all
• Excreted unchanged in the urine

Biguanides Actions:

• Inhibits hepatic gluconeogenesis
• Enhances insulin-mediated glucose disposal in muscle and fat
• Retards intestinal absorption of glucose
• Promotes peripheral utilization of glucose

Biguanides Use:

• Used in obese patients with type II diabetes

Biguanides Contra-Indications:

• Hypotension
• CVS diseases
• Respiratory diseases
• Hepatic and renal diseases
• Alcoholics

Insulin And Oral Hypoglycaemics Short Question And Answers

Question 1. Advantages of newer insulins.
Answer:

Derived from the human pancreas.

• So, lesser risks of antigen-antibody reactions.
• They are highly purified.
• Can be used in insulin resistance diabetes
• Can be used during pregnancy.
• Can be used in case of injection site lipodystrophy.

Question 2. Sulphonylurea.
Answer:

Sulphonylurea was the first oral hypoglycaemic drug introduced.

Sulphonylurea Classification:

1. First generation – tolbutamide and chlorpropamide.

2. Second generation – Glibenclamide, glipizide.

Sulphonylurea Uses:

• Maturity onset diabetes.
• Insulin resistant diabetes
• Diabetes insipidus.

Question 3. Tolbutamide.
Answer:

Tolbutamide is an oral hypoglycaemic drug.

• It is first generation sulphonylurea.

Tolbutamide Features:

• Weaker
• Short-acting.
• Flexible dosage.
• Safer for those prone to hypoglycaemia.
• Daily dose – 0.4 – 3 g.
• Half-life – 6 – 8 hours.
• Duration of action – 6 – 8 hours.

Tolbutamide Use:

• Type II diabetes mellitus.

Question 4. Glibenclamide.
Answer:

Glibenclamide is an oral hypoglycaemic drug.

• It is second generation sulphonylurea.

Glibenclamide Features:

• Potent
• Slow acting.
• Marked insulinemic action.
• Effective in a single dose.
• Higher incidence of hypoglycaemia.
• Plasma t ½ – 4 – 6 hours.
• Duration of action – 18 – 24 hours.
• Daily dose 5-15 mg.

Glibenclamide Use:

Type II diabetes mellitus.

Question 5. Insulin preparations.
Answer:

Based on onset and duration of action, insulin preparations are:

1. Rapid acting.

• Insulin lispro, insulin aspart, insulin glulisine.

2. Short-acting – regular insulin.

3. Intermediate-acting – insulin zinc suspension iso-phane insulin.

4. Long-acting – protamine zinc insulin, insulin glargine.

Question 6. Uses of insulin.
Answer:

Uses are diabetes is not controlled by diet and exercise.

• Primary or secondary failure of oral hypoglycaemic drugs.
• In underweight patients.
• Temporary to overcome infections, trauma, and surgery.
• In complications of diabetes like ketoacidosis, gangrene of extremities.

Question 7. Drug treatment of juvenile diabetes.
Answer:

Juvenile diabetes is insulin-dependent diabetes mellitus.

• It is immune-mediated.

juvenile diabetes Treatment:

• Insulin therapy along with diet
• Started with regular insulin parenterally before each major meal.
• Condition is assessed by regular testing of urine or
• blood glucose level.

Question 8. Adverse effects of insulin.
Answer:

• Hypoglycaemia.
• Local reactions – swelling, erythema and stinging.
• Localized lipodystrophy.
• Allergy – urticaria, angioedema and anaphylaxis.

Question 9. Oral hypoglycaemic drugs.
Answer:

1. Sulphonylurea.

• First generation – Tolbutamide, chlorpropamide.
• Second generation – Glibenclamide, glipizide.

2. Biguanide – metformin.

3. Meglitinide analogues – repaglinide, nateglinide.

4. Thiazolidinediones – rosiglitazone, pioglitazone.

5. Alpha glucosidase inhibitors.

• Acarbose, miglitol.

6. Dipeptidyl peptidase – 4 inhibitor.

• Sitagliptin, vildagliptin.

Question 10. Protamine zinc insulin.
Answer:

It is a long-acting oral hypoglycaemic drug.

• The onset of action – 4 – 6 hours.
• Duration of action – 24 – 36 hours.
• It can be mixed with regular insulin.
• Produces relatively low, smooth and peakless blood Insulin levels.
• Once daily administration produces constant Insulin action.

Question 11. Glimepiride.
Answer:

• It is second generation sulphonylurea
• Has stronger extrapancreatic action
• Has less hyperinsulinaemia
• Daily dose – 1-6 mg
• Plasma half-life – 5-7 hours
• The duration of action is 24 hours