Drugs for Diabetes Flashcards
List 3 drug interactions which enhance the hypoglycemic effect of Sulfonylureas.
- Displaced from binding with plasma proteins by other highly protein bound drugs: sulfonamides, clofibrate, salicylates
- Enhancing the effect on KATP channel: ethanol
- Inhibition of CYP enzymes: azole antifungals, gemfibrozil, cimetidine, etc.

What are the 2 non-sulfonylureas (meglitinides) used for tx of diabetes?
- Nateglinide
- Repaglinide

Which underlying condition should be corrected before using SGLT2 inhibitors (-gliflozins)?
Hypovolemia
List some of the advantages of using Metformin as a first-line agent for T2DM
- Superior or equivalent glucose-lowering efficacy compared to other oral meds
- Does not cause hypoglycemia or weight gain
- Can be taken orally and used alone or in combo w/ other oral agents
- Clinical trials show a ↓ risk of both macro- and microvascular complications
What are 3 common causes of hypoglycemia as an AE in patient on insulin therapy?
- Delayed of meal or a missed meal
- Exercise —> ↑ consumption of glucose by muscle + hyperemic skin has ↑ rate of insulin absorption
- Overdose of insulin
The use of Metformin is contraindicated in which patients?
- Pt’s w/ conditions predisposing to tissue hypoxia (HF, COPD), renal failure, chronic alcoholism and cirrhosis
- May cause lactic acidosis as AE, which can worsen hypoxia

Which property of the long-acting GLP-1 agonist, Liraglutide, makes it have such a long half-life?
Lipid-modified - so is rapidly absorbed, but binds to albumin

List 3 AE’s associated with the non-sulfonylureas (meglitinides)?
- Hypoglycemia
- Secondary failure
- Weight gain
What are the 2 α-glycosidase inhibitors used for diabetes?
- Acarbose
- Miglitol

What is the clinical use of Metformin?
Most commonly used oral agent for T2DM and is generally accepted as the FIRST-LINE tx

List 4 clinical uses for using short-acting, regular insulin?
- Basal insulin maintenance
- Overnight coverage
- Postprandial hyperglycemia - but must inject 45 min before meal
- Can be given IV in urgent situations

What is the clinical use of the long-acting insulins, Detemir and Glargine; how are they administered?
- Basal insulin maintenance
- 1-2 SQ injections daily
What is the MOA of diazoxide and why is it used for hypoglycemia induced by insulin therapy?
- Strong hyperglycemic agent –> K+-ATPchannelopener
- Inhibits release of insulin by beta cells

What are the three, 2nd generation Sulfonylureas used for diabetes?
- Glipizide
- Glyburide
- Glimepiride

What are 3 AE’s associated with the DPP-4 inhibitors (-gliptins)?
- Upper respiratory infections and nasopharyngitis
- Linked to acute pancreatitis
- Hypoglycemia (if combined w/ insulin secretagogues - their doses have to be adjusted)
List 3 drug interactions which decrease the glucose lowering effect of Sulfonylureas.
- Inhibiting insulin secretion: beta-blockers and CCBs
- Antagonizing their effect on KATP channel: diazoxide
- Inducing hepatic CYP enzymes: phenytoin, griseofulvin, rifampin, etc.

What are the three, 1st generation Sulfonylureas used for diabetes?
- Chlorpropamide
- Tolbutamide
- Tolazamide

What is the MOA of the Sulfonylureas used for tx of diabetes?
- Bind to sulfonylurea receptor (SUR) of pancreatic β-cells
- Block K+ current through Kir6.2 inwardly rectifying potassium channel
- Cell depolarizes –> insulin release via ↑ Ca2+ influx

List 6 AE’s associated with the SGLT2 inhibitors (-gliflozins).
- Hypotension
- Hypovolemia
- Hypoglycemia if combo w/ insulin or insulin secretagogues
- Genital (mycotic) and UTI’s
- Renal function impairment due to ↓ GFR
- Hyperkalemia –> esp. in pt’s w/ impaired renal function and those on ACEIs, ARBs, and K+-sparing diuretics

List 3 cross-reactivity drug interactions associated with the Sulfonylureas used for diabetes.
- Sulfonamide antibiotics
- Carbonic anhydrase inhibitors
- Diuretics (thiazides, furosemide)

What is the drug that is an intermediate-acting insulin called?
Neutral Protamine Hagerdorn (NPH)
What is the MOA of the SGLT2 inhibitors?
- Block reabsorption of glucose in proximal convoluted tubule
- ↑ glucose excretion and reduced hyperglycemia

List 4 actions of amylin secreted by pancreatic β-cells
- Inhibits glucagon secretion
- Enhances insulin sensitivity
- ↓ gastric emptying (slows rate of intestinal glucose absorption)
- Causes satiety

By which mechanism are the thiazolidinediones, pioglitazone and rosiglitazone associated with edema as an AE?
- ↑ vascular permeability
- ↑ expressio of ENaC –> ↑ Na+ and H2O reabsorption in collecting duct
What is the clinical use for the α-glycosidase inhibitors, acarbose and miglitol, how and when are they administered, and what are their benefits?
- Use in T2DM as monotherapy or in combo w/ other oral antidiabetics or insulin
- Taken orally at mealtime
- Do not cause hypoglycemia when used alone
- Do not cause weight gain

What are the 2 thiazolidinediones used for diabetes?
- Pioglitazone
- Rosiglitazone

Which cells synthesize and secrete GLP-1?
Intestinal L-cells
Which drugs are given for severe hyperkalemia and explain why each is given?
- Insulin (IV) + glucose (to prevent hypoglycemic shock) + furosemide
- Insulin (IV) rapidly activates Na/K-ATPase to shift K+ into cells
- K+ is eliminated from the body using the loop diuretic, furosemide

What are the four DPP-4 inhibitors used in the tx of diabetes?
- Sitagliptin
- Alogliptin
- Linagliptin
- Saxagliptin
**The -gliptins

What are the clinical uses for the amylin analog, Pramlintide; how is it administered?
- T1DM
- T2DM pt’s who take mealtime insulin therapy
- Injected SQ before mals as an ajunct to insulin therapy
What is the clinical use for the rapid-acting insulin drugs, aspart, lispro, and glulisine; how are they administered?
Post-prandial hyperglcemia - take before meal via SQ injections

What is the composition of the intermediate-acting insulin, neutral protamine hagerdon, and how does this relate to its pharmacokinetics?
- Complex of protamine w/ zinc insulin
- Protamine has to be digested by tissue proteolytic enzymes before insulin can be absorbed
Where is amylin secreted from and what is the amylin analog used for diabetics?
- Pancreatic β-cells
- Amylin analong drug = Pramlintide

List 4 of the AE’s assoc. with the Sulfonylureas used for diabetes
- Hypoglycemia
- Weight gain (↑ insulin release)
- Secondary failure = pt’s who respond initially later cease to respond to sulfonylureas and develop unacceptable hyperglycemia
- Dermatologic and general hypersensitivity rxns –> SULFA drugs!!!

What are the 3 SGLT2 inhibitors used for diabetes?
- Canagliflozin
- Dapagliflozin
- Empagliflozin

What is the clinical use of the long-acting GLP-1 receptor agonists?
Approved for T2DM pt’s who are NOT adequately controlled by metformin/sulfonylureas/thiazolidinediones

What is the MOA of the biguanide, Metformin?
- Activation of AMP-dependent protein kinase, leading to:
- Inhibition of lipogenesis and gluconeogenesis
- ↑ in glucose uptake + glycolysis + FA oxidation + insulin sensitivity
- Lowers glucose levels in hyperglycemic state (but not normoglycemic)

Why is there a lower risk of hypoglycemia when using long-acting GLP-1 receptor agonists vs. pramlintide (amylin analog)?
- Exhibits glucose-DEPENDENT insulinotropism
- GLP-1 receptor agonists stimulate insulin secretion during hyperglycemia but NOT during hypoglycemia

Which mutations from the human sequence of insulin allow for fast absorption of the rapid-acting insulin drugs?
Block assembly of dimers and hexamers

What makes the absorption rate of short-acting, regular insulin, slower and less predictable?
Form hexamers, which are too bulky to be transported via endothelium into the blood stream
What are some of the AE’s associated with thiazolidinediones, pioglitazone and rosiglitazone?
- Weight gain and Edema (incidence doubled if administered w/ insulin)
- Exacerbation of HF
- ↑ total cholesterol and LDL-C (rosiglitazone)
- ↑ risk of fracture –> osteoporosis (especially postmenopausal women)
What is the clinical use of the intermediate-acting insulin, neutral protamine hagerdon (NPH)?
- Basal insulin maintenance and/or overnight coverage
- Use is declining due to being replaced by long-acting insulins
What is used in the tx of hypoglycemia as a complication of insulin therapy?
- Glucose: juice or candy if conscious; IV glucose if unconscious
- Diazoxide: inhibits release of insulin by beta cells
- Glucagon (SQ)
What are the AE’s associated with Metformin?
- Most common = GI = anorexia, N/V, diarrhea, abdominal discomfort
- ↓ absorption of vit B12
- Lactic acidosis, especially under conditions of hypoxia, renal and hepatic insufficiency
What is a drug interaction you must be aware of when using the amylin analog, Pramlintide?
Enhances effects of anticholinergic drugs in GI tract –> Constipation
What is the molecular composition of the long-acting insulin, Detemir, and how is this related to its pharmacokinetics?
- Lys 29 in B chain is myristoylated (lipid)
- Rapid absorbed into blood but binds strongly to albumin
What are 2 ligands for GPCR-Gs which enhance the secretion of insulin?
- β2-AR agonists
- GLP-1 receptor agonists (incretins)

What are drug-drug interactions specific to the α-glycosidase inhibitor acarbose and to miglitol?
- ↓ absorption of digoxin (acarbose)
- ↓ absorption of propranolol and ranitidine (miglitol)

What are the 2 long-acting insulins?
- Detemir
- Glargine
What is the MOA of the DPP-4 inhibitors (-gliptins) used in diabetes?
- Prevent the degradation of GLP-1 and other incretins
- Leads to ↓ glucagon release, gastric emptying
- ↑ glucose-dependent insulin release, satiety

What are the AE’s of the α-glycosidase inhibitors, acarbose and miglitol?
- Most common = malabsorption, flatulence, diarrhea, and bloating
- Hypoglycemia when used in combo with insulin or insulin secretagogues
- Not recommended if kidney function impaired

What are the clinical uses for the thiazolidinediones, pioglitazone and rosiglitazone?
- Use in T2DM, alone or in combo w/ other antidiabetics
- Shown to delay progression from prediabetes to T2DM***
- Euglycemic drugs (no hypoglycemia when used alone)

What are the 2 long-acting GLP-1 receptor agonists used for diabetes?
- Exenatide
- Liraglutide

What is the molecular composition of the long-acting insulin, Glargine, and how is this related to its pharmacokinetics?
- AA substitution in both A and B chains enhance crystal stability, change pKA of insulin
- Soluble at low pH (4) but precipitates at pH 7
List some potential AE’s of using insulin drugs.
- Hypoglycemia = most common
- Lipodystrophy
- Resistance
- Allergic rxns —> immediate type hypersensitivity = rare
- Hypokalemia

What are 2 ligands for GPCR-Gi which inhibit the secretion of insulin?
- Somatostatin
- α2-AR agonists (remember α2 uses a Gi)

What is the clinical use for the non-sulfonylureas (meglitinides); how are they administered route and timing?
- Control of postprandial hyperglycemia in pt’s w/ T2DM
- Taken orally BEFORE meal
- Can be used either alone (isolated postprandial hyperglycemia) or in combo w/ other antidiabetic drugs
What are 5 actions of the incretin, GLP-1?
- Promotes β-cell proliferation + insulin gene expression + glucose-dependent insulin secretion
- Inhibits glucagon secretion
- Causes satiety, by inhibiting gastric emptying

How are the thiazolidinediones, pioglitazone and rosiglitazone administered and what is significant about their pharmacokinetics?
- Orally once daily
- Onset is delayed –> full effect develops after 1-3 months
- Effect persists after drugs are eliminated for weeks-months

What are some of the AE’s associated w/ the amylin analog, Pramlintide?
- GI: nausea, vomiting, diarrhea, anorexia
- Severe hypoglycemia: especially if used together w/ insulin (↓ dose of insulin)
List the 3 rapid-acting insulin agents
- Aspart
- Lispro
- Glusine
What is the MOA of the thiazolidinediones, pioglitazone and rosiglitazone?
- Activate PPAR-γ (a nuclear receptor) expressed in fat, muscle, liver, and endothelium
- ↑ insulin sensitivity and levels of adiponectin + ↑ GLUT4

What are some of the immediate and long-term AE’s of the long-acting GLP-1 receptor agonists?
- GI: nausea, vomiting, diarrhea, and anorexia
- Linked to cases of acute pancreatitis and pancreatic cancer!!!

How was the long-acting GLP-1 receptor agonist, Exendatide made less susceptible to the hydrolysis by DPP-4?
Glycine substitution
What is the clinical use for the DPP-4 inhibitors (-gliptins); how are they administered?
- Adjunctive therapy to diet + exercise in pt’s w/ T2DM
- Used as monotherapy and in combo w/ metformin/sulfonylureas/TZDs
- Taken orally
How are thiazolidinediones, pioglitazone and rosiglitazone metabolized and how does this effect the pt populations who can take the drugs?

- Metabolized by the liver; so half-life can be reduced by CYP-inducer (rifampin) or prolonged by CYP-inhibitors (gemfibrosil)
- Safe to administer to pt’s with renal failure
Which long-acting GLP-1 receptor agonist has the longest half-life?
- Liraglutide = 11-15 hrs ***
- Exenatide = 2.4 hrs
What is the clinical use, route of administration, and timing for the SGLT2 inhibitors (-gliflozins)?
- Taken orally before the first meal 1x/day
- Used as adjunct to diet + exercise in adults w/ T2DM

What is the clinical use of Sulfonylureas for diabetes?
T2DM as a monotherapy or in combo w/ insulin or other anti-diabtetics
How does the peak of actions differ between the long-acting insulin Detmir and Glargine?
- Detemir peaks from 3-9 hours
- Glargine is peakless!

Which patients are the thiazolidinediones, pioglitazone and rosiglitazone contraindicated in?
Pt’s w/ NYHA class III or IV heart failure

What is the MOA of the α-glycosidase inhibitors, acarbose and miglitol?
- Competitively inhibit intestinal brush border α-glycosidases —> delayed CHO hydrolysis and glucose absorption
- ↓ postprandial hyperglycemia to create insulin-sparing effect

Other than ↑ excretion of glucose in the urine, what are 5 other effects of SGLT2 inhibitors?
- Cause osmotic diuresis
- Induce weight loss
- ↓ BP
- ↓ plasma levels of uric acid
- Do not cause hypoglycemia when used alone

How can resistance to exogenous insulin develop?
- Pt’s commonly develop insulin binding antibodies
- IgG antibodies can neutralize the action of insulin