Diabetes is guaranteed exam territory, and it clusters into three testable blocks: the insulins themselves, the two hyperglycemic crises, and hypoglycemia management. Master the three and most diabetes items become recognition, not reasoning.
| Insulin | Type | Onset | Peak (danger zone) | Notes |
|---|---|---|---|---|
| Lispro / Aspart | Rapid-acting | ~15 min | ~1 hour | Give with the meal in front of the client. |
| Regular | Short-acting | 30–60 min | 2–3 hours | The only insulin given IV. Clear. |
| NPH | Intermediate | 2–4 hours | 4–12 hours | Cloudy. The one mixed with regular. |
| Glargine | Long-acting | ~1–2 hours | Peakless | Never mixed with anything. |
Mixing rule the exam can't resist: draw up clear before cloudy (regular before NPH) so the NPH never contaminates the rapid vial. And peaks are when hypoglycemia strikes — schedule snacks and vigilance by the peak, not the injection.
| DKA | HHS | |
|---|---|---|
| Typical client | Type 1 | Type 2, often elderly |
| Glucose | > 250 mg/dL | Often > 600 mg/dL |
| Ketones & acidosis | Present — pH low, Kussmaul respirations, fruity breath | Absent/minimal — no significant acidosis |
| Dehydration | Severe | Even more profound |
| First priority | IV fluids first, then IV insulin; watch potassium — insulin drives K⁺ into cells, and total-body potassium falls as the crisis corrects | |
Symptoms split into adrenergic (shaky, sweaty, tachycardic, hungry — the early warning) and neuroglycopenic (confusion, slurred speech, behavior change — the late, dangerous one). Conscious client: 15 g fast carbohydrate, recheck in 15 minutes, repeat if still below 70. Unconscious or unsafe to swallow: IV dextrose 50% or IM glucagon — never oral fluids. And the surgical classic: a client on a beta blocker may feel only the sweating, because the drug masks tremor and tachycardia.
Practice. A client with type 1 diabetes is found sweaty, trembling, and anxious. Glucose reads 58 mg/dL. The client is awake and can swallow. First action?
A. Give the scheduled insulin dose and recheck in an hour
B. Give 4 oz (120 mL) of orange juice
C. Call the provider before intervening
D. Offer a sandwich with peanut butter
Answer: B — 15 g of fast-acting carbohydrate, then recheck in 15 minutes. Fat and protein (D) slow absorption; insulin (A) would worsen it; the protocol treats first (C delays it).
Sick-day rules, foot care, Somogyi vs dawn phenomenon, long-term complications — the Core Bundle's Med-Surg and Pharmacology modules cover the full cluster, with diabetes drills in Drill Set 3.
Next Gen NCLEX questions are where exams are won and lost. Our free field guide walks through every NGN item type — case study, bow-tie, trend, cloze, matrix — with fully worked examples and the scoring explained in plain English.