Low Blood Pressure Symptoms

Presentation of low blood pressure is highly variable and can range from totally asymptomatic to life-threatening emergency requiring immediate medical intervention. The symptoms depend on various factors like:

1. The exact value of blood pressure readings.

A blood pressure of 55/35 mm Hg would have different presentation than a blood pressure of 85/55 mm Hg, although both are "low blood pressure".

2. The cause of the low blood pressure.

Symptoms would vary depending upon the primary condition (if any) that is causing the low blood pressure.

3. How rapidly the condition has progressed.

A rapidly progressing fall in blood pressure in blood pressure (e.g. shock) is more likely to be serious and symptomatic than a slowly progressing fall (which allows for compensatory mechanisms to take effect).

Low blood pressure per se can give rise to numerous symptoms like dizziness, fatigues, exercise intolerance, blurring of vision, fainting, confusion, shortness of breath, chest pain, pale and cold skin, etc. Moreover, there might be symptoms due to primary condition that is causing the low blood pressure. Low blood pressure in shock can lead to more serious picture, and the affected person can be cold, pale, disoriented or unconscious and may even die if appropriate treatment is not instituted urgently.

The low blood pressure can result in inadequate supply of oxygen to the brain, resulting in symptoms like dizziness, headache or even loss of consciousness for some time. Very low blood pressure for prolonged time can permanently cause ischemic damage to the neurons in the brain.

Similarly, low blood pressure can result in inadequate supply of oxygen to heart muscles and thus affecting their proper functioning. This may result in symptoms like chest pain (often similar to angina pain) and shortness of breath. Also, since the heart is being forced to beat at a much faster rate (reflex response to low blood pressure), the person may feel his heart beat (called palpitations).

Pale and cold skin is due to constriction of the peripheral vessels (e.g. in the skin). This constriction allows for diversion of blood from less important organs (like skin) to vital organs like heart and brain.

Symptoms of low blood pressure would also depend greatly on the condition causing low blood pressure. In postural hypotension, the main symptoms are dizziness or fainting when a person tries to stand up from a lying down or sitting position. However, in aortic stenosis, the same dizziness or fainting would be experienced while doing some strenuous work. Similarly, low blood pressure due to hypothyroidism or hyperthyroidism would be associated with other symptoms of thyroid dysfunction.