"Pharmacology Oral Glycemics I & II Ruth Weinstock" Flashcards
What causes type 1 DM?
Autoimmune destruction of insulin- producing pancreatic beta cells
Insulin therapy is required
How does a healthy pancreas work in the islets of Langerhans?
α-cells secrete glucagon • β-cells secrete insulin
How do the islets of Langerhans work in a person with T2DM?
α-cells dysfunction: secrete inappropriately high levels of glucagon
Fewer β-cells: secrete insufficient levels of insulin
β-cell mass declines over time
T2DM Is Marked by Blunted Insulin Response and Inadequate Glucagon Suppression After Meals
What are the functions of glucagon-like hormone (GLP-1)?
- Enhances glucose-dependent insulin secretion
- Slows gastric emptying
- Suppresses glucagon secretion
- Promotes satiety
- Receptors in the islet cells, CNS, elsewhere
- Metabolized rapidly (half-life 2-3 min) by DPP-4 (dipepetidyl peptidase-4)
T/F: GLP-1 release is reduced in T2DM?
True
Without insulin, effect of eating produces hyperglycemia
What is the first line pharmacological therapy for T2DM?
At the time of type 2 diabetes diagnosis, initiate metformin therapy along with lifestyle interventions, unless metformin is contraindicated
In newly diagnosed type 2 diabetes patients with markedly symptomatic and/ or elevated blood glucose levels or A1C, consider insulin therapy, with or without additional agents, from the
outset
If noninsulin monotherapy is unsuccessful in the treatment of T2DM, what is the next step?
add a second oral agent, a GLP-1 receptor agonist, or insulin
Class: Metformin
*Tx of Hyperglycemia in T2DM
Biguanide
MOA: Metformin
*Tx of Hyperglycemia in T2DM
Reduces hepatic glucose production by Activating AMP-kinase and inhibits mitochondrial isoform of glycerophosphate dehydrogenase
What are the advantages of metformin?
*Tx of Hyperglycemia in T2DM
No weight gain (weight neutral)
• No hypoglycemia
• Reduction in cardiovascular events and mortality
• Possibly less cancer
What are the disadvantages of metformin?
*Tx of Hyperglycemia in T2DM
Gastrointestinal side effects (diarrhea, abdominal cramping, anorexia)
• Lactic acidosis (rare)
• Vitamin B12 deficiency
In what patient population is metformin contraindicated?
*Tx of Hyperglycemia in T2DM
In patients with reduced kidney function
Class: Glibenclamide/Glyburide
*Tx of Hyperglycemia in T2DM
Sulfonylureas (2nd generation)
Class: Glipizide
*Tx of Hyperglycemia in T2DM
Sulfonylureas (2nd generation)
Class: Gliclazide
*Tx of Hyperglycemia in T2DM
Sulfonylureas (2nd generation)
Class: Glimepiride
*Tx of Hyperglycemia in T2DM
Sulfonylureas (2nd generation)
What is the MOA of the sulfonylureas drugs? • Glibenclamide/Glyburide • Glipizide • Gliclazide • Glimepiride
*Tx of Hyperglycemia in T2DM
Closes K-ATP channels on beta cell plasma membranes to increase insulin secretion
T/F: The sulfonylureas drugs are well tolerated.
*Tx of Hyperglycemia in T2DM
True • Glibenclamide/Glyburide • Glipizide • Gliclazide • Glimepiride
What are the disadvantages of the sulfonylureas drugs?
*Tx of Hyperglycemia in T2DM
- Relatively glucose-independent stimulation of insulin secretion: Hypoglycemia, including episodes necessitating hospital admission and causing death
- Weight gain
- May blunt myocardial ischemic preconditioning
Class: Repaglinide
*Tx of Hyperglycemia in T2DM
Meglitinides
Class: Nateglinide
*Tx of Hyperglycemia in T2DM
Meglitinides
MOA: Meglitinides (Repaglinide, Nateglinide)
*Tx of Hyperglycemia in T2DM
Same as the sulfonylureas: Closes KATP channels on β-cell plasma membranes to increase insulin secretion
What are the advantages of the Meglitinides (Repaglinide and Nateglinide) over the sufonylureas drugs?
*Tx of Hyperglycemia in T2DM
Accentuated effects around meal ingestion (short- acting)
What are the side effects of the Meglitinides (Repaglinide and Nateglinide)?
*Tx of Hyperglycemia in T2DM
- Hypoglycemia
- Weight gain
- May blunt myocardial ischemic preconditioning
- Dosing frequency (before each meal)
Class: Pioglitazone
*Tx of Hyperglycemia in T2DM
Thiazolidinediones (Glitazones)
MOA: Pioglitazone
*Tx of Hyperglycemia in T2DM
Activates the nuclear transcription factor PPAR-γ to increase peripheral insulin sensitivity
What are the advantages of Pioglitazone?
*Tx of Hyperglycemia in T2DM
- No hypoglycemia
- HDL cholesterol ↑
- Triglycerides ↓
- Possible reduction in myocardial infarctions
What are the disadvantages of Pioglitazone?
*Tx of Hyperglycemia in T2DM
- Weight gain
- Edema
- Heart failure
- Bone fractures
- Increased bladder cancer risk
Class: Rosiglitazone
*Tx of Hyperglycemia in T2DM
Thiazolidinediones (Glitazones)
Rosiglitazone is similar to pioglitazone in its MOA, but has different disadvantages. What are they?
*Tx of Hyperglycemia in T2DM
• LDL cholesterol ↑ • Weight gain • Edema • Heart failure • Bone fractures • Increased cardiovascular events (mixed evidence)
Rosiglitazone is contraindicated in patients with what condition?
*Tx of Hyperglycemia in T2DM
Heart disease
Class: Acarbose
*Tx of Hyperglycemia in T2DM
α-Glucosidase inhibitors
Class: Miglitol
*Tx of Hyperglycemia in T2DM
α-Glucosidase inhibitors
MOA: α-Glucosidase inhibitors (Acarbose and Miglitol)
*Tx of Hyperglycemia in T2DM
Inhibits intestinal alpha-glucosidase in order to slow intestinal carbohydrate digestion and thus glucose absorption
What are the advantages of the α-Glucosidase inhibitors (Acarbose and Miglitol)?
*Tx of Hyperglycemia in T2DM
- Nonsystemic medication
- Postprandial glucose ↓
- Weight neutral
- No hypoglycemia
What are the disadvantages of the α-Glucosidase inhibitors (Acarbose and Miglitol)?
*Tx of Hyperglycemia in T2DM
- Gastrointestinal side effects (gas, flatulence, diarrhea, abdominal fullness and discomfort)
- Dosing frequency
- Modest reduction in A1c
Class: Exenatide
*Tx of Hyperglycemia in T2DM
GLP-1 receptor agonists (incretin mimetics)
Dose Exenatide twice daily or weekly - injectible
Class: Liraglutide
*Tx of Hyperglycemia in T2DM
GLP-1 receptor agonists (incretin mimetics)
Dose Liraglutide daily - injectible
Class: Albiglutide
*Tx of Hyperglycemia in T2DM
GLP-1 receptor agonists (incretin mimetics)
Dose Albiglutide weekly - injectible
Class: Dulaglutide
*Tx of Hyperglycemia in T2DM
GLP-1 receptor agonists (incretin mimetics)
Dose Dulaglutide weekly - injectible