Blood pressure guides, ranges, symptoms, treatment and home monitoring

Hypertension is persistent high blood pressure. Primary hypertension develops without one single identifiable cause, while secondary hypertension is linked to an underlying condition such as kidney disease, hormonal disorders or obstructive sleep apnea.

Common modifiable factors include excess sodium intake, physical inactivity, excess body weight, alcohol intake and chronic stress. Because hypertension often causes no symptoms, repeated measurement is essential for detection.

Hypotension is commonly described as blood pressure below 90/60 mmHg. Low readings are not always harmful when a person feels well, but symptoms such as dizziness, fainting, blurred vision or weakness can indicate reduced blood flow and need medical assessment.

Potential causes include dehydration, blood loss, prolonged bed rest, medications, endocrine disorders and autonomic dysfunction.

Home blood pressure monitoring is most useful when measurements are taken with a validated upper-arm cuff, after a period of quiet rest, with the arm supported at heart level.

Taking repeated readings under similar conditions helps reduce measurement error and gives a clinician a more useful picture than one isolated number.

Diet influences blood pressure through fluid balance, vascular tone and hormonal pathways. The DASH dietary pattern emphasizes vegetables, fruit, whole grains, low-fat dairy and lean protein while limiting sodium, saturated fat and added sugars.

Alcohol, caffeine, sodium and potassium can also influence readings, although the effect varies by dose, timing and individual sensitivity.