Diabetes Mellitus Drugs

Question 1

What is diabetes Mellitus

Answer 1

a metabolic disorder which causes hyperglycaemia (high blood glucose levels)

Question 2

Where is the insulin hormone made?

Answer 2

in the beta-cells of the pancreas

Question 3

What types of diabetes is insulin used to treat

Answer 3

Types 1 (absolute deficiency) and sometimes Type 2 (relative deficiency) in insulin, when resistant to oral drugs.

Question 4

What is the treatment of choice in pregnant patients?

Answer 4

insulin

Question 5

What are the 5 types of insulin formulation and how long does each last up to?

Answer 5

ultra-rapid acting 10-15 min onset, up to 4 hrs duration), ,short acting .5-1 hour onset, duration up to 8 hours), intermediate acting short onset (1-2 hours) up to 24 hours duration, long acting slow onset (2-4 hours) up to 36 hours duration

Question 6

how is long acting Insulin often used?

Answer 6

to provide a basal amount of insulin, then topped up with rapid, short or intermediate acting insulin doses before meals.

Question 7

What are the ADR of insulin?

Answer 7

hypoglycaemia most common.

Question 8

In what 4 situations does hypoglycaemia from insulin often occur

Answer 8

meals are skipped/delayed, too little carbs eaten, too much insulin dose, increase in exercise

Question 9

what are the symptoms of hypoglycaemia and what are the two reasons they arise from?

Answer 9

tachycardia, palpitations, nervousness, irritability, hunger, sweating (related to insulin release)
difficulty concentrating, mental confusion, headache, incoherant speech, aggression, drowsiness, unconsciousness, coma (related to decreased glucose to the brain)

Question 10

what are drug interactions of insulin?

Answer 10

corticosteroids, B-blockers, thiazide diuretics

Question 11

What is the other type of diabetes mellitus group of drugs besides insulin?

Answer 11

Oral Hypoglycaemic Agents (OHA’s)

Question 12

What type of diabetes are OHAs used for and why?

Answer 12

Type 2 diabetes, as depend on some residual insulin secretion for their function.

Question 13

How are OHA’s used?

Answer 13

as an adjunct to dietary control, weight loss and exercise, and before insulin.

Question 14

What are 4 classes of Oral Hypoglycaemic Agents?

Answer 14

Biguanides, Sulfonylureas, Glitazones, alpha-glucosidase inhibitors,

Question 15

What is the mechanism of action of OHAs generally (5 of them)

Answer 15

• stimulate further insulin release
• lower insulin resistance
• sensitize cells to actions of insulin
• reduce glucose load (eg inhibit gluconeogenesis)
• alter CHO absorption

Question 16

How are the Biguanides generally used (eg as what type of therapy?)

Answer 16

1st line of therapy for type 2 diabetes

Question 17

What is the drug name of a Biguanide?

Answer 17

Metformin

Question 18

what is the mechanism of action for metformin?

Answer 18

it is an antihyperglycaemic not a hypoglycaemic agent. increases insulin sensitivity, increases glucose uptake into muscles, decreases gluconeogenesis

Question 19

Who is metformin the preferred drug for

Answer 19

• obese people (no weight gain)
  elderly (no hypoglycaemia when used alone)
  when diabetes is not controlled by diet and exercise

Question 20

What are the ADR of metformin?

Answer 20

GI upsets (common), lactic acidosis,

Question 21

Warnings/CI for metformin

Answer 21

limit use in people with renal or hepatic impairment, a history of alcohol abuse or lactic acidosis. Avoid in severe liver/kidney disease, cardiac disorders.

Question 22

When are sulfonylureas indicated?

Answer 22

for uncomplicated type 2 diabetes, second line of treatment

Question 23

what is an example of a Sulfonylurea drug?

Answer 23

Glibenclamide

Question 24

what is the mechanism of action of sulfonylureas?

Answer 24

Bind to receptors and block ATP-sensitive potassium channels (K_ATP) in beta pancreatic ccells, blocking outflow of K+ and causing depolarisation, which opens Ca2+ channels and causes insulin release. Increased insulin release causes increased cell sensitivity to insulin, and decreased insulin resistance.

Question 25

What are the ADR of sulfonylureas?

Answer 25

hypoglycaemia (too much insulin release)
weight gain
GI disturbances

Question 26

What are the warnings/contraindications of sulfonylureas?

Answer 26

elderly
hepatic/renal impairment
pregnancy and lactation

Question 27

What is the mechanism of action of Glitazones

Answer 27

increase cell sensitivity to insulin, reducing insulin resistance in the liver and peripheral tissues (stimulates the PPAR-gamma receptor)

Question 28

What are the ADR of Glitazone?

Answer 28

heart failure risk
hepatic toxicity
weight gain
anaemia

Question 29

What are the warnings/contraindications for Glitazone?

Answer 29

hepatic impairment

Question 30

What is the mechanism of action for alpha-glucosidase inhibitors (Acarbose)?

Answer 30

It inhibits the enzyme alpha-glucosidase that digests carbohydrates in the SI, delaying digestion and absorption of CHOs, lessening glucose release after eating.

Question 31

What are the ADR of alpha-glucosidase inhibitors?

Answer 31

GIT - flatulence, bloating

Question 32

What is the mechanism of action of insulin

Answer 32

It has all the properties and actions of the natural hormone. Binds to receptor in target cell, causes GLUT-4 transporter to be taken to cell membrane. GLUT-4 receptor actively transports glucose into cell.