Hypoglycemic agent

Definition: The drugs which are used to lower the blood sugar are called as hypoglycemic agents.

Classifications of Hypoglycemic agent:

1. Hormones: e.g. Insulin and its preparations

2. Oral hypoglycemic agents:

a. Sulphonylureas: e.g. chlorpropamide, Tolbutamide, Glibenclamide

b. Biguanides: e.g. Phenformine, Metformin

3. Plant products: guar gum

Insulin

• It is hormone produced by beta cell of islets of langerhans of pancreas.

• It is polypeptide containing 51 amino acid arranged in two chains namely A and B having 21 and 30 amino acid respectively.

• The two chains are connected by two disulphide bridges (-s-s bond of cysteine) (source: pancreas of pig or Ox)

Properties of Insulin:

• It is white powder.

• It is slightly soluble in water

• It dissolve in dilute solution of mineral and acid

• It is inactivated by photolytic enzymes

• It is soluble in alkali hydroxide.

Stability and storage: it is sensitive to heat and light, hence it is stored in well closed containers at room temperature below 8 degree Celsius.

• Insulin injection is stored in multidose containers at room temperature between 20 and 8 degree Celsius and should not be allowed to freeze.

• The label on the containers should be bear 

1. Number of unit per ml.

2. The animal source of insulin

3. Expiry date

4. Storage condition with precaution that

a) It should not be allowed to freeze.

b) The containers should be shaken gently before withdrawal of dose.

Uses of Insulin:

• To control diabetes mellitus or to treat insulin dependent diabetes mellitus.

• To regulate carbohydrate metabolism.

• To treat gyperkalaemia.

• To treat severe ketoacidosis or coma

Pharmaceutical formulations of Insulin:

• Insulin injection

• Neutral Insulin injection.

• Biphasic Insulin injection 

• Globin zinc Insulin injection

• Isophane Insulin injection

• Protamine zinc Insulin injection

• Insulin zinc suspension

Chlorpropamide

Structure of Chlorpropamide

Chemical name: N – (p-chlorobenzene sulphonyl) N, -propyl urea.

Properties of Chlorpropamide:

• It occurs as white crystalline powder which is odorless and tasteless.

• It is practically insoluble in water

• But soluble in alcohol and solution of alkali hydroxide.

Storage: it is stored in well closed containers

Uses of Chlorpropamide:

• To treat non -insulin dependent diabetes mellitus

• Mild to moderate diabetes insipidus

Pharmaceutical formulations: ChlorpropamideTablets

Brand names: Diabetol, Diabetin, Chloroformin

Tolbutamide

Properties of Tolbutamide:

• It occurs as white crystalline powder

• It is odorless

• It is practically insoluble in water.

• Soluble in alcohol, sodium hydroxide, dilute mineral acids.

Storage: stored in well closed containers

Uses of Tolbutamide:

• To control blood glucose in previously untreated non-insulin dependent diabetes mellitus.

• In treatment of diabetes mellitus when blood glucose is unsatisfactory despite with diet.

• In conjugation with Metformin, if the drug alone fail to control blood glucose level.

Dosage form: Tolbutamide tablets

Brand names: Tolbutab, Rastinon

Phenformine

Structure of Phenformine

Chemical names: 1-(2-phenyl ethyl) biguanidine

Properties of Phenformine:

• It is official as a hydrochloride salt.

• It is white crystalline powder.

• It is odorless

• It has bitter taste.

• It is freely soluble in water.

• It is soluble in alcohol.

Storage: stored in well closed containers

Uses of Phenformine:

• To treat non –insulin dependent diabetes mellitus.

• To reduce the blood sugar level in cortisone induced hyperglycemia.

• To reduce the blood cholesterol in maturity onset diabetes

Dosage forms: Phenformine Tablets

Brand names: Sucronase, Bislim

Metformin

Properties of Metformin:

• It is hydrochloride salt.

• It is white crystalline powder.

• It is odourless.

• It has bitter taste.

• It is hygroscopic in nature.

• It is freely soluble in water.

• Practically insoluble in chloroform.

Stability and storage: it is hygroscopic and hence it is stored in tightly closed containers.

Uses of Metformin:

• To treat non –insulin dependent diabetes mellitus.

• Insulin dependent diabetes mellitus in combination with insulin.

• Diabetes associated with Hyperlipoproteinemia.

• Obesity

Dosage forms: Metformin tablets

Brand names: Diabex, Diaformin

Glibenclamide / Glyburide

Properties of Glibenclamide:

• It is white crystalline powder.

• It is odourless.

• It is very slightly soluble in water.

• It is sparingly soluble in chloroform.

Storage: stored in well closed containers

Uses of Glibenclamide:

• To treat the non-insulin dependent diabetes mellitus, either alone or with combination with controlled diet or in combination with biguanidine.

• As a substitute for other hypoglycaemic agent which cause undesirable side effects.

• As a possible substitute for insulin in non-insulin dependent diabetes mellitus.

Dosage forms: Tablets

Brand names: Daonil, Euglucon