Reference — Endocrine

Diabetes Medications Reference

Major diabetes medication classes — mechanism, hypoglycemia risk, key side effects, nursing considerations, and NCLEX pearls for metformin, sulfonylureas, GLP-1 agonists, SGLT2 inhibitors, DPP-4 inhibitors, and insulin.

Educational use only. Medication selection and dosing are provider decisions; verify every dose against current orders and facility policy before administration. This material supports nursing education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional policy, or medical direction. Always follow facility protocols and current provider orders.

Hypoglycemia risk key: Insulin and sulfonylureas are the primary agents that cause hypoglycemia — they stimulate insulin release or replace insulin directly. GLP-1, SGLT2, and DPP-4 agents have glucose-dependent mechanisms and carry low monotherapy hypoglycemia risk.

Biguanides

Hypoglycemia: No (monotherapy) — does NOT stimulate insulin release

Examples: Metformin (Glucophage)

Mechanism: Decreases hepatic glucose production (gluconeogenesis); improves peripheral insulin sensitivity

Key Effects / Side Effects

✦GI upset (nausea, diarrhea, bloating) — take with food
✦Lactic acidosis (rare but serious — hold for contrast dye, surgery, renal impairment)
✦Weight neutral or modest weight loss
✦B12 deficiency with long-term use

Nursing Considerations

→Stop at the time of (not in advance of) IV contrast or surgery, withhold for 48 hours after, and restart once renal function is confirmed stable; for IV contrast with eGFR ≥30 and no AKI, current ACR/FDA guidance is that no hold is required
→Monitor eGFR — contraindicated if eGFR <30 mL/min
→First-line therapy for Type 2 DM per ADA guidelines
→Check B12 levels annually in long-term users

NCLEX: Hold metformin before IV contrast and procedures. Risk: lactic acidosis.

Sulfonylureas

Hypoglycemia: YES — high risk, especially glyburide

Examples: Glipizide, Glyburide, Glimepiride

Mechanism: Stimulates insulin release from pancreatic beta cells (independent of blood glucose) → can cause hypoglycemia

Key Effects / Side Effects

✦Hypoglycemia (most important concern)
✦Weight gain
✦Glyburide = highest hypoglycemia risk; avoid in elderly
✦Glipizide = shorter duration, safer in elderly

Nursing Considerations

→Monitor blood glucose closely — especially with illness, missed meals, exercise
→Teach patient to always eat when taking sulfonylurea
→Glyburide — avoid in renal impairment and elderly (Beers Criteria)
→Alcohol + sulfonylurea: flushing reaction (Antabuse-like) with chlorpropamide (older, rarely used)

NCLEX: Sulfonylureas cause hypoglycemia. Must eat meals when taking. Avoid glyburide in elderly.

GLP-1 Receptor Agonists

Hypoglycemia: Low risk (glucose-dependent) — hypoglycemia possible if combined with insulin or sulfonylurea

Examples: Liraglutide (Victoza), Semaglutide (Ozempic, Wegovy), Exenatide (Byetta), Dulaglutide (Trulicity)

Mechanism: Mimics GLP-1 hormone: ↑ insulin secretion (glucose-dependent), ↓ glucagon, slows gastric emptying, ↑ satiety

Key Effects / Side Effects

✦Nausea/vomiting (especially early in treatment)
✦Significant weight loss (clinically important)
✦Pancreatitis (rare but serious — stop if abdominal pain)
✦Not for Type 1 DM
✦Cardiovascular benefit (liraglutide, semaglutide)

Nursing Considerations

→Inject subcutaneously (all SQ or oral semaglutide)
→Teach injection technique and rotation
→Warn about nausea — start low dose, escalate slowly
→Hold if pancreatitis suspected (severe abdominal pain radiating to back)
→Contraindicated: personal/family history of medullary thyroid cancer or MEN2

NCLEX: GLP-1 agonists: weight loss, minimal hypoglycemia, GI side effects, pancreatitis risk.

SGLT2 Inhibitors

Hypoglycemia: Low risk (mechanism is glucose-dependent/renal)

Examples: Empagliflozin (Jardiance), Dapagliflozin (Farxiga), Canagliflozin (Invokana)

Mechanism: Blocks glucose reabsorption in the kidney → glucosuria (glucose excreted in urine) → lowers blood glucose

Key Effects / Side Effects

✦Genital mycotic infections (yeast infections — glucosuria feeds Candida)
✦UTI risk
✦Euglycemic DKA (SGLT2-associated DKA with near-normal glucose)
✦Urinary frequency/polyuria
✦Cardiovascular and renal protection
✦Weight loss, modest BP lowering

Nursing Considerations

→Teach genital hygiene; expect urinary frequency
→Hold before surgery (canagliflozin/dapagliflozin/empagliflozin 3 days, ertugliflozin at least 4 days per FDA) or prolonged fasting — risk of euglycemic DKA
→Monitor for UTI symptoms; treat promptly
→Canagliflozin: increased lower extremity amputation risk — monitor foot care
→Check eGFR — glucose-lowering effect diminishes in renal impairment

NCLEX: SGLT2 inhibitors: yeast infections, UTI, euglycemic DKA. Hold before surgery.

DPP-4 Inhibitors

Hypoglycemia: Very low risk

Examples: Sitagliptin (Januvia), Saxagliptin (Onglyza), Linagliptin (Tradjenta), Alogliptin (Nesina)

Mechanism: Inhibits DPP-4 enzyme that degrades GLP-1 → prolongs GLP-1 action → ↑ insulin (glucose-dependent), ↓ glucagon

Key Effects / Side Effects

✦Upper respiratory infections
✦Nasopharyngitis
✦Pancreatitis (rare)
✦Joint pain
✦Weight neutral

Nursing Considerations

→Well-tolerated overall — few major nursing concerns
→Monitor for upper respiratory symptoms
→Hold if pancreatitis suspected
→Saxagliptin/alogliptin: may increase heart failure hospitalizations — monitor if HF history

NCLEX: DPP-4 inhibitors: minimal side effects, no hypoglycemia. Upper respiratory infections.

Insulin (overview)

Hypoglycemia: YES — all insulins can cause hypoglycemia

Examples: Rapid (lispro, aspart), Short (regular), Intermediate (NPH), Long-acting (glargine, detemir)

Mechanism: Replaces or supplements endogenous insulin → facilitates cellular glucose uptake; suppresses hepatic glucose production

Key Effects / Side Effects

✦Hypoglycemia (most critical side effect)
✦Weight gain
✦Injection site lipohypertrophy with poor rotation
✦Hypokalemia (insulin drives K⁺ into cells)

Nursing Considerations

→HIGH-ALERT medication — verify dose with second nurse
→Rotate injection sites; inspect injection sites
→Rapid-acting: give with meals or hold if patient cannot eat
→Long-acting: never mix with other insulins
→Monitor glucose per protocol — before meals and bedtime minimum

NCLEX: Insulin = HIGH-ALERT. Know onset/peak/duration. Hypoglycemia is the primary risk.

Related Resources

Insulin Types ReferenceOnset, peak, duration, and nursing notes for all insulin formulations

Open →

Glycemic Targets ReferenceGlucose goals, A1C targets, hospital thresholds, and hypoglycemia cutoffs

Open →

Diabetes Mellitus FundamentalsType 1 vs Type 2, complications, and nursing overview

Open →

High-Alert MedicationsInsulin safety practices and verification requirements

Open →

Standards & sources

Fact-checked Jun 20, 2026

This page is written to align with American Diabetes Association (ADA) Standards of Care · American Association of Clinical Endocrinology (AACE). It is an educational summary, not a citation of any single document — always verify specific doses, values, and protocols against current guidelines and your facility policy. How we source content →