Warning Signs of Hypertension: Symptoms to Know

High blood pressure is called the "silent killer" for a reason: most people with hypertension feel completely normal, sometimes for years, while the extra pressure slowly damages the heart, brain, kidneys and eyes. The only reliable way to know your blood pressure is to measure it.

Why there are usually no symptoms

Arteries and organs adapt to rising pressure gradually, so the body does not send an alarm. Many people only find out about their hypertension during a routine check-up — or after a heart attack or stroke. That is why waiting for symptoms is a poor strategy.

Headaches and nosebleeds: not reliable signs

Many people believe high blood pressure causes headaches, dizziness, nosebleeds or a red face. In reality:

• Headaches are common in everyone. Studies have found little link between ordinary headaches and moderately raised blood pressure. Only extremely high pressure (usually 180/110 or higher) can cause a severe headache.
• Nosebleeds are mostly caused by dry air, nose picking or blood thinners — not usually by hypertension.
• Flushing, dizziness or feeling "tense" do not tell you what your blood pressure is. Many people with very high readings feel nothing at all.

Feeling fine is therefore no proof that your blood pressure is fine — and feeling unwell is no proof that it is high.

Signs of a hypertensive emergency

When blood pressure rises very steeply — to 180/110 or higher (stage 3 in the international categories; the US guideline uses above 180/120) — it can damage organs within hours. Symptoms that point to this include:

• chest pain or pressure
• shortness of breath
• severe back pain
• numbness or weakness in the face, arm or leg, especially on one side
• difficulty speaking or understanding speech
• sudden blurred or lost vision
• confusion, drowsiness or a sudden, very severe headache
• seizures

A reading of 180/110 or higher without such symptoms (above 180/120 is called severe hypertension in the US guideline) is not usually an emergency. Sit quietly for five minutes and measure again; if it is still that high, contact your doctor the same day. See Hypertension Stage 3 (180/110 and Above): Act Now for more on very high readings.

Signs that hypertension has already caused damage

After years of untreated high blood pressure, symptoms may come from the organs that have been affected. These signs need a medical check-up soon:

These symptoms have many possible causes, so they do not prove hypertension — but they are a good reason to have your blood pressure, kidneys and heart checked.

When to measure your blood pressure

• Every adult: at least every two to three years if your readings are optimal or normal, and every year from age 40.
• Every year or more often if you have high-normal blood pressure, overweight, diabetes, kidney disease, a family history of hypertension or other risk factors.
• At home regularly if you have been diagnosed with hypertension or your doctor suspects it — a validated upper-arm monitor is best.
• During pregnancy at every prenatal visit.

Learn how to get accurate numbers in Measuring Blood Pressure Correctly: Step by Step, and compare your result with the normal blood pressure ranges. A typical first sign is simply a reading such as 145/92 on a routine check — no symptoms at all.