Updated July 2026 · 8 min read

Preeclampsia & Eclampsia 2026 — Two Jobs, Two Drugs, One Cure

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Preeclampsia is a whole-body vascular disease of pregnancy that can end in stroke, seizure, or organ failure — and it does not always announce itself before it turns dangerous. The nurse who understands that magnesium and blood-pressure control are two different jobs, and who watches for the warning signs of eclampsia and magnesium toxicity, protects two patients at once.

What preeclampsia actually is

Preeclampsia is new-onset hypertension plus end-organ involvement after 20 weeks of pregnancy — it is a whole-body vascular disease, not just a high blood pressure. The placenta is the origin, but the damage shows up in the mother's kidneys (proteinuria, rising creatinine), liver (RUQ pain, rising transaminases), brain (headache, visual changes, hyperreflexia, seizures), blood (falling platelets, hemolysis), and lungs (pulmonary edema). "Severe features" — a systolic ≥160 or diastolic ≥110, platelets under 100k, doubling creatinine, transaminases twice normal, pulmonary edema, or new cerebral/visual symptoms — mark the patients who belong on a monitored unit. Eclampsia is preeclampsia that has progressed to a generalized seizure, and it can be the first sign in a woman who never looked that sick.

The two jobs: stop the seizure risk, control the pressure

These are separate problems with separate drugs, and mixing them up is the classic error. Magnesium sulfate is for seizure prophylaxis and treatment — it is not a blood pressure medication and will not fix a severe-range pressure. Antihypertensives (IV labetalol, IV hydralazine, or oral/IV nicardipine) are for the pressure — they do nothing to prevent seizures. A patient with severe-range hypertension needs both, and severe-range pressure should be treated within about an hour to protect against maternal stroke, which is the leading cause of death in this disease.

And the underlying truth: delivery is the only cure. Everything else is buying time and protecting the mother's brain, liver, and kidneys until the baby can be delivered safely.

Magnesium: the drug that treats and the drug that poisons

Magnesium is remarkably effective at preventing eclamptic seizures, but it has a narrow safety margin and is cleared by the kidneys — so in a patient with falling urine output or rising creatinine, the level climbs fast. Toxicity marches in a predictable order, and the nurse's serial exam catches it long before a level comes back. Loss of deep tendon reflexes is the first and most important warning: reflexes disappear before breathing is threatened, so an areflexic patient means stop and reassess before respiratory depression arrives.

What the bedside nurse owns

This disease rewards structure. Keep the environment quiet and the patient on continuous monitoring; a rising or pounding headache, visual changes, brisk hyperreflexia with clonus, or new epigastric/RUQ pain are the warning signs that a seizure or HELLP is coming, and they are yours to catch and escalate. Track strict intake and output — oliguria is both an organ-injury marker and a magnesium-toxicity risk. Listen to the lungs, because pulmonary edema is a real and dangerous complication and these patients are sensitive to fluid. Have magnesium, an antihypertensive, and calcium gluconate ready before you need them. And remember the seizure itself: if eclampsia occurs, it is protect-the-airway, position for safety, and give magnesium — the seizure is usually self-limited, and the priority is preventing aspiration and injury while the team moves toward delivery.

Related reading: HELLP syndrome, postpartum hemorrhage, labetalol & nicardipine for hypertensive emergency, and IV magnesium replacement.