Endocrine Drugs

Question 1

What is first line Rx for hypothyroidism?

Answer 1

Levothyroxine
1.6 micrograms/kg if <65 - titrate every 4-6w

Question 2

How often should Ps on levothyroxine been monitored once established?

Answer 2

Adults - annually

Children >2 = every 4-6m until puberty, then annual
Children <2 = every 2-3m in 1st year, 3-4m in 2nd year

Question 3

What are the main treatments for hyperthyroidism?
How do they work?

Answer 3

Carbimazole
Propylthiouracil

Both inhibit TPO = reduced T4 and T3

Can either start on high carbimazole and reduce dose as thyroid function settles

OR
Continue on high carbimazole and add thyroxine in to keep T4 at required levels.

Question 4

What are the major side effects of carbmizaole?

Answer 4

Agranulocytosis (high mortality) - watch for sore mouth, throat, infection
Hepatitis / Cholestasis
Vasculitis
TERATOGENIC

Question 5

What are the major side effects of propylthiouracil?

Answer 5

Agranulocytosis
Safer to carbimazole in 1st trimester

Question 6

Answer 6

Question 7

Answer 7

Question 8

When starting a P on metformin - why do you need to ensure that CrCl is >30ml/min?

Answer 8

To reduce risk of lactic acidosis

Question 9

How do we monitor diabetic control when starting new drugs?

Answer 9

Aim for HbA1c of 48 or less

Monitor every 3-4m until it remains stable on unchanging therapy.

Question 10

How does clopidogrel interact with omeprazole?

Which other PPI could you use instead?

Answer 10

Omeprazole inhibitors CYP2C19 - which is needed to metabolise clopidogrel. Therefore you get reduced anti platelet affect when using both.

Could use lansoprazole or pantoprazole instead - as neither of these interact with clopidogrel.

Question 11

When should metformin be given and why?

Answer 11

With a meal = to reduce the risk of GI side effects.

Question 12

Which diabetic medication is contraindicated in Ps with recurrent UTIs?

Answer 12

SGLT2 inhibitors

Question 13

What is the main SE of Pioglitazone?

Answer 13

Can cause weight gain of 2-3kg average over 12m

Question 14

If you have a severely overweight P on Metformin who needs a second medication, but they have recurrent UTIs - which medication should you add on?

Answer 14

Shouldn’t give SGLT2 - as they can cause UTIs

Pioglitazone and Sulfonylureas can both cause weight gain.

Therefore consider adding on GLP1 agonist - which has the weight loss advantage.