Drug of the Day: Metformin

Question 1

What is the trade name for metformin?

Answer 1

Glucophage, Glucophage XR, Fortamet

Question 2

What is the drug class for metformin?

Answer 2

biguanide

Question 3

What is the primary indication of metformin?

Answer 3

Type 2 Diabetes

(if not contraindicated, it is considered the first drug of choice)

Question 4

What two things does metformin DECREASE during its mechanism of action?

Answer 4

1. hepatic glucose production
2. intestinal glucose absorption

Question 5

What two things does metformin INCREASE during its mechanism of action?

Answer 5

1. hepatic glycogen stores
2. peripheral glucose uptake utlization
   
   • this improves insulin sensitivity

Question 6

The primary indication is Type 2 Diabetes, but another indication of metformin includes?

Answer 6

polycystic ovarian syndrome

Question 7

Name 3 more frequent incidences under the key adverse effects from taking metformin.

Answer 7

1. anorexia (loss of appetite)
2. dyspepsia (indigestion)
3. flatulence

Question 8

What are two rare incidences under the key adverse effects from taking metformin?

Answer 8

1. lactic acidosis
   
   • ​low pH in body tissues and blood accompanied by the buildup of lactate
2. hypoglycemia
   
   • ​low blood sugar

Question 9

What are three monitoring parameters when taking metformin?

Answer 9

1. blood glucose: fasting and HbA_1c
   
   • goal is less than 7%
2. periodic monitoring of hematologic parameters
   
   • hemoglobin and hematocrit
3. annual evaluation of renal function
   
   • SCr and BUN

Question 10

What are the 4 key patient counseling points when taking metformin?

Answer 10

1. take exactly as prescribed
2. signs and symptoms of hypoglycemia and hyperglycemia and what to do if they occur
3. how to test blood sugar
4. take with food

Question 11

For the immediate release dose, What is the initial adult dosing of metformin?

Answer 11

500 mg po bid

or

850 mg po qd

Question 12

For the immediate release dose, the initial adult dosing of metformin is 500 mg po bid or 850 mg po qd. When should a patient titrate up?

Answer 12

1-2 week intervals to a maximum of 2550 mg/day

Question 13

For the immediate release dose, the initial adult dosing of metformin is 500 mg po bid or 850 mg po qd. The patient can titrate up at 1-2 week intervals to a maximum of 2550 mg/day. Doses that are more than 2000 mg/day may be?

Answer 13

better tolerated if doses were divided into 3 daily doses

Question 14

For the extended release dose of Fortamet, the initial adult dosing is ____?

Answer 14

1000 mg qd

Question 15

For the extended release dose of Fortamet, the initial adult dosing is 1000 mg po qd and is increased by ____ at weekly intervals with a max of ____?

Answer 15

500 mg qd

max: 2500 mg/day

Question 16

For the extended release dose of Glucophage XR, the initial adult dosing is ___?

Answer 16

500 mg po qd

Question 17

For the extended release dose of Glucophage XR, the initial adult dosing is 500 mg po qd and is increased by ____ at weekly intervals with a max of ____?

Answer 17

500 mg po qd

max: 2000 mg/day

Question 18

For the extended release dose of Glumetz, the initial adult dosing is ___?

Answer 18

1000 mg po qd

Question 19

For the extended release dose of Glumetz, the initial adult dosing is 1000 mg po qd and is increased by ____ at weekly intervals with a max of ____?

Answer 19

500 mg po qd

max: 2000 mg/day

Question 20

Is is necessary to adjust the dosing for patients with renal function impairment?

Answer 20

Yes. Adjust the dosing down

it is contraindicated for patients with renal disease

SCr > or = to 1.5 in males

SCr > or = 1.4 in females

Question 21

It is necessary to adjust the dosing down for patients with renal function impaitment and also the?

Answer 21

elderly