RE Pharm Flashcards
Biguanides (METFORMIN) mechanism of action
Stimulates AMPK (AMP-activated protein kinase), which activates insulin signalling and increases insulin-dependent glucose uptake. This leads to:
- a reduction in gluconeogenesis
- increased insulin receptor expression
- increased levels of Glucagon-like peptide 1 (GLP1) and - inhibition of synthesis of glucose, lipids, and protein
- stimulation of glucose uptake and FA oxidation
Which class of drug is recommended for patients with insulin resistance?
Biguanides (Metformin)
What are the common and rare side effects of Biguanides (Metformin)?
Common: GI- mainly bloating and diarrhea. 5% of patients are intolerant to the medication. Headaches. B12 deficiency due to reduced absorption- risk increases with duration of therapy
Uncommon: Hypoglycaemia (but can be seen with combination therapy)
Rare side effects include:
- LACTIC ACIDOSIS - Haemolytic anaemia - Cholestatic jaundice - Allergic pneumonitis - Leucocytoclastic vasculitis
Contraindications for Biguanides (Metformin)
- Acute metabolic acidosis (including lactic acidosis and DKA)
- eGFR < 30 mL/min/1.73m2 - increased risk of developing lactic acidosis
- Liver dysfunction
Sulphonylurea (GlicKlazide & Glimpiride) mechanism of action:
Blocks potassium ATP channels within beta cells of the pancreas, stimulating insulin secretion
Side effects associated with sulphonylureas (GlicKlazide & Glimepiride)
Hypoglycaemia, weight gain, and secondary failure
(NB on secondary failure: Hyperexcitation of beta cells –> excitotoxic reaction –> beta cell apoptosis –> beta cell mass loss –> insulin deficiency)
Key trial data for ______________ showed a decrease in HbA1c by 1-2%, high rates of hypoglycaemia, cardioprotective, and weight gain
Sulphonylureas (GlicKlazide & Glimpiride)
Contraindications to sulphonylureas (GlicKlazide & Glimepiride)
- Ketoacidosis
- Acute porphyria
- Caution in elderly (d/t risk of hypoglycaemia), obesity (d/t weight gain) and G6PD deficiency (d/t the way it is metabolised)
SGLT2 inhibitors (Dapagliflozin, Canagliflozin, Empagliflozin) MOA
- Decreases rental tubular glucose reabsorption
- Lowers glucose without increasing insulin release
- Diuretic effect
Trials have shown this class of drug reduces HbA1c by 0.6-1.2%, contributes to significant reduction in all-cause mortality, significant reduction in CV mortality, and significant reduction in CV death and hospitalization for heart failure
SGLT2 inhibitors (Dapagliflozin, Canagliflozin, Empagliflozin)
Side effects of SGLT2 inhibitors (Dapagliflozin, Canagliflozin, Empagliflozin)
- EUGLYCAEMIC DKA
- Genital and UT infections
- Urinary retention
- Hypotension- d/t diuretic effect
- Reduced bone density
Contraindications of SGLT2 inhibitors (Dapagliflozin, Canagliflozin, Empagliflozin)
- Patients at risk of DKA
- Cautions in elderly patients, heart failure, CKD
Glucagon-like peptide-1 (GLP-1) agonists (Dulaglutide, Exanatide, Liraglutide, Semaglutide MOA:
- Stimulate insulin release
- Reduces glucose sensitivity
- Enhances pancreatic beta cell replication
- Prevents beta-cells from decline
- Delayed gastric emptying
- Inhibition of glucagon secretion
Common and rare side effects of Glucagon-like peptide-1 (GLP-1) agonists (Dulaglutide, Exanatide, Liraglutide, Semaglutide
Common:
- GI (nausea and loose stools)
- Hypersensitivity
- Local skin reactions to injection sites
Rare:
- Possible increase in medullary thyroid cancer (therefore contraindicated in high risk individuals)
- Risk of antibody formation- therefore if increased hypersensitivity reaction or lack of improved HbA1c, discontinue GLP1 agonist
- Renal impairment- contra-indicated in chronic kidney failure
Contraindications for Glucagon-like peptide-1 (GLP-1) agonists (Dulaglutide, Exanatide, Liraglutide, Semaglutide
- Diabetic gastroparesis
- IBD
- Age >75 years
- DKA
- Diabetic retinopathy (Semaglutide)
- Hx of pancreatitis
- Severe congestive heart failure
Side effects of insulin therapy
- Hypoglycaemia (accounts for up to 6% of deaths in T1DM patients)
- Weight gain
- Reaction at injection site
- Cancer-risk- non consistent results
- Cardiovascular risk (? Related to hypoglycaemia?)
Which of the diabetes drugs can reduce weight?
GLP-1 agonists (-tides)
Possibly d/t delayed gastric emptying leading to N/V –> reduced appetite.
Which diabetes drug enhances insulin signalling in insulin-dependent and insulin-independent pathways?
Biguanides (Metformin)
Starting dose of Metformin is _____ mg QD with largest meal
Titrate every two weeks by 500 mg until they achieve __ gram BID
500 mg
1 gram
DM2 management:
If HbA1c rises to ____ mmol/mol on lifestyle interventions alone, offer standard- release _________.
48
Metformin
DM2 management (first intensification):
If Hba1c rises to ____ mmol/mol with Metformin alone, consider dual therapy with either Metformin and
_________ or Metformin and ________.
58 mmol/mol
Metformin + sulfonylurea (GlicKlazide) OR
Metformin + SGLT (-flozins)
DM2 management:
If Metformin therapy is contraindicated or otherwise not tolerated, the patient can start on either a __________ or ___________.
Sulphonylurea (GlicKlazide) OR SGLT inhibitor (-flozin)
DM2 management (second intensification):
If Hba1c rises to _____ mmmol/mol on dual therapy, consider triple therapy with:
Metformin + Suphonylurea + ________
Or Metformin + Sulphonylurea + ___________
Alternatively, it may be appropriate to start _______-based therapy at this stage
58
SGLT inhibitor
GLP1 agonist
Insulin
First line/gold standard insulin regimen for treatment of T1DM?
Basal-bolus insulin regimen or multi-daily injection (MDI) therapy
This is a pre-mixed insulin which is 30% short acting insulin and 70% intermediate acting insulin.
Rarely used in type 1
Requires a consistent daily routine that includes three meals a day.
Risk of hypo or hyperglycemia if not consistent with meals
Pre-mixed insulin regime (e.g. Novomix)
Most widely prescribed anti-thyroid medication in the UK. MOA is to inhibit thyroid peroxidase, thereby reducing production of T4 and T3
Carbimazole
MOA of Propylthiouracil?
Inhibits TPO- reducing production of T4 and T3. Also reduces peripheral conversion of T4 into T3