Endocrine Drugs Flashcards
What are the 3 main classes of drugs used to treat type 2 diabetes?
Give an example of each.
Biguanides (e.g. metformin)
Sulphonylureas (e.g. gliclazide)
GLP1 agonist (e.g. liraglutide)
Describe the mechanism of action of metformin. (2)
What sort of drug is this?
Biguanide
- Increases the activity of AMP-dependent protein kinase (AMPK)
a. This inhibits gluconeogenesis - Also reduces insulin resistance
List 2 indications for metformin.
Type 2 diabetes mellitus
Metabolic/reproductive abnormalities in PCOS
List 7 side effects of metformin.
Which important side effect is NOT caused by metformin?
Diarrhoea Weight loss Nausea Vomiting Taste disturbances Lack of appetite Lactic acidosis (in renal failure)
NOT CAUSED BY METFORMIN:
Hypoglycaemia
Describe the important pharmacokinetics/dynamics of metformin. (3)
What would you tell the patient when prescribing metformin? (3)
PHARMA: Avoid in: -Pregnancy -Renal failure (GFR <30ml/min) Absorption reduced when taken with food
PATIENT INFO:
Take at the same time everyday
Avoid alcohol
Will cause weight loss
Give 2 examples of sulphonylureas.
List 1 indication for prescribing them.
Gliclazide
Glimepride
T2DM
Describe the mechanism of action of sulphonylureas. (2)
- Stimulates beta cells in the pancreas to produce more insulin
- Increases cellular glucose uptake and glycogenesis
a. Also reduces gluconeogenesis
List 7 side effects of sulphonylureas.
Hypoglycaemia Rashes Nausea Vomiting Stomach pain Indigestion Weight gain
Describe the important pharmacokinetics/dyanmics of sulphonylureas. (2)
What would you tell the patient when prescribing them? (3)
PHARMA:
Renal excretion - accumulate in renal failure
Gliclazide - short acting
Glimepride - long acting
PATIENT INFO:
Compliance is important
Maintain consistent diet
Avoid alcohol
Give 2 examples of GLP1 (glucagon like peptide) agonists.
List 1 indication for prescribing them.
Exanatide
Liraglutide
T2DM
Describe the mechanism of action of GLP1 agonists. (3)
- GLP1 is a hormone release after meals to increase insulin secretion
- GLP1 agonists mimic this, causing increase insulin secretion
- Also causes decreased glucagon secretion and reduces hunger
List 4 side effects of GLP1 agonists.
Hypoglycaemia
Nausea
Vomiting
Diarrhoea
Describe the important pharmacokinetics/dynamics of GLP1 agonists. (2)
What would you tell the patients when prescribing them? (2)
PHARMA:
Improves glucose control when given with metformin, SUs and/or insulin
Renal excretion - dose adjustment needed in renal failure
PATIENT INFO:
Only given as injections
Twice a day
Apart from metformin, SUs and GLP1 agonists, which 6 other drugs can be used to treat T2DM?
Give an example of each.
Thiazolidinedione (TZDs), e.g. pioglitazone
DDP4 inhibitors, e.g. sitagliptin
Insulin, e.g. Novorapid
Sulphonylurea receptor binder, e.g. glibenclamide
Alpha glucosidase inhibitors, e.g. acarbose
SGLUT2 inhibitors, e.g. empagliflozin
How do you treat hypothyroidism?
What type of drug is this?
Levothyroxine
Synthetic thyroid hormone
Describe the mechanism of action of thyroxine. (4)
- Thyroxine (T4) increases the metabolic rate of all tissues in the body
- Levothyroxine is a synthetically prepared levo-isomer of thyroxine
- Levothyroxine acts like T4
a. Converted into T3 in the liver and kidneys - T3 maintains brain function, food metabolism and body temperature
List 2 indications for levothyroxine.
Hypothyroidism
Chronic lymphocytic thyroiditis
List 6 side effects of levothyroxine.
Chest pain Coma Diarrhoea Tachycardia Itching Muscle cramps
NOTE: very uncommon is dosing is good
Describe the important pharmacokinetics/dynamics of levothyroxine. (3)
What would you tell the patient when prescribing this? (1)
PHARMA:
Renal clearance
IV formulation is available
Long half life (6-7 days) therefore TFTs should be rechecked 6 weeks after dose adjustment
PATIENT INFO:
Take 30-60 mins before breakfast
How would you treat hyperthyroidism?
Give 2 examples of this drug class.
Thionamides
Carbimazole
Propylthiouracil
Describe the mechanism of action of thionamides. (3)
- Reduce activity of peroxidase enzyme
a. Therefore inhibits thyroid hormone formation - May also reduce peripheral conversion of T4 to T3
- Carbimazole is a pro-drug
List 3 indications for thionamides.
Hyperthyroidism
Thyrotoxicosis
Preparing patients for thyroid surgery
List 3 side effects of thionamides.
Rash
Agranulocytosis
Sore throat
Describe the important pharmacokinetics/dyanmics of thionamides. (3)
What would you tell the patient when prescribing them? (2)
PHARMA:
Carbimazole metabolised to thiamazole within 1 hour
Thiamazole crosses the placenta and can be found in breast milk
Usually prescribed with a beta blocker to reduce symptoms
PATIENT INFO:
Compliance is important
Regular blood checks needed for treatment response, LFTs, U&Es and FBCs
Which class of drug is used to treat osteoporosis?
Give 2 examples.
Bisphosphates
Alendronate (alendronic acid)
Ibandronate
Describe the mechanism of action of bisphosphates. (2)
- Inhibit osteoclast bone resorption
2. No effect on bone formation
List 3 indications for bisphosphates.
Post-menopausal osteoporosis
Reducing risk of vertebral and hip fractures
Paget’s disease of bone
List 5 side effects of bisphosphates.
Abdominal pain Dyspepsia Acid regurgitation Dysphagia Headache
Describe the important pharmacokinetics/dynamics of bisphosphates. (1)
What would you tell the patient when prescribing them? (2)
PHARMA:
Bioavailability reduced by coffee/orange juice
PATIENT INFO:
Take 30 minutes before food
Avoid caffeine
Give 2 examples of the OCP.
What kinds of pill are they?
Microgynon (combined)
Cerazette (progesterone only)
Describe the mechanism of action of the OCP. (4)
- OCP can be combined or progesterone-only
- OCP acts on the female reproductive tract, the mammary glands, hypothalamus and pituitary gland
- OCP reduces production of gonadotrophin releasing hormone (GnRH)
- This prevents the LH surge, therefore prevents ovulation
List 3 indications for the OCP.
Contraception
Menopausal and postmenopausal disorders
PCOS
List 5 side effects of the OCP.
Mood swings Headache Breast tenderness Increased risk of breast/varian cancer Increased risk of venous thromboembolism
Describe the important pharmacokinetics/dynamics of the OCP. (1)
What would you tell the patient when prescribing it? (3)
PHARMA:
Antibiotics and St John’s Wort can reduce efficacy
PATIENT INFO:
Take at the same time every day
Take with food
Use alternative forms of contraception when taking antibiotics/enzyme inducers
Describe the mechanism of action of thiazolidinediones (TZDs). (3)
What are they used for?
T2DM
- PPAR gamma agonist
- Acts as a transcription factor and stimulates genes involved in triglyceride storage in adipose tissue
a. This prevents inappropriate fat deposition
b. Therefore improves insulin sensitivity - Decreases adipokine production
a. Therefore improves insulin sensitivity
List 4 side effects of DPP4 antagonists.
GI upset
Rash
Flu-like symptoms
Pancreatitis
Describe the mechanism of action of SGLUT2 inhibitors.
What are they used for?
T2DM
- Inhibit glucose reabsorption in kidneys
- Increased excretion of glucose in urine
List 4 side effects of SGLUT2 inhibitors.
UTIs
Acute kidney injury
DKA
Acute pancreatitis
