Primary: the common, multi-cause kind
In about nine out of ten people, high pressure has no single, removable cause. This is primary hypertension (also called essential hypertension). It emerges from a tangle of small contributors — genes, age, salt handling by the kidneys, body weight, alcohol, stress, and a gradual rise in systemic vascular resistance as small arteries tighten and stiffen. No one switch is to blame, which is exactly why treatment leans on lifestyle plus medication rather than a single cure.
Secondary: a cause worth hunting for
In the remaining minority, the pressure is driven by a specific, identifiable problem — secondary hypertension. Common culprits include kidney disease, narrowing of a kidney artery (renovascular hypertension), hormone-producing tumours, thyroid disorders, and sleep apnoea. The reward for finding one is large: treating or removing the cause can sometimes cure the hypertension outright, rather than merely controlling it for life.
Urgency vs emergency: it is about damage, not the number
A very high reading — say above 180/120 — is alarming, but what matters most is whether an organ is being acutely harmed right now. If the pressure is sky-high but the person feels well and no acute damage is found, that is hypertensive urgency, usually managed with calm, gradual lowering over hours to days. If the pressure is causing active injury — to the brain (stroke, confusion), heart (chest pain, failure), eyes, or kidneys — that is a hypertensive emergency, needing immediate, carefully controlled treatment in hospital.
- Confirm the reading with a properly sized cuff after a few minutes of rest.
- Ask about emergency symptoms: severe headache, vision change, chest pain, breathlessness, weakness, confusion.
- If such symptoms are present, this is an emergency — seek immediate care; do not just take an extra pill at home.
- If no acute symptoms, this is urgency — pressure is lowered gently, not crashed down, to avoid harming organ blood flow.