What Causes BP Low?
September 6, 2023 | by Yashaswi Pathakamuri | Posted in FAQ's
Low blood pressure, also known as hypotension, can have various causes. It’s important to note that what’s considered a “normal” blood pressure can vary from person to person, but generally, a blood pressure reading below 90/60 mm Hg is considered low. Here are some common causes of low blood pressure:
- Dehydration: Inadequate fluid intake can lead to a decrease in blood volume, which, in turn, lowers blood pressure. Dehydration can occur due to not drinking enough water, excessive sweating, vomiting, or diarrhea.
- Medications: Some medications, such as antihypertensives (drugs used to treat high blood pressure), diuretics, and certain antidepressants, can lower blood pressure as a side effect.
- Heart problems: Conditions like heart failure, bradycardia (a slow heart rate), and heart valve disorders can lead to low blood pressure because the heart is unable to pump blood effectively.
- Endocrine disorders: Hormonal imbalances, such as thyroid disorders (hypothyroidism), adrenal insufficiency, and Addison’s disease, can cause low blood pressure.
- Blood loss: Severe bleeding from injury, surgery, or internal bleeding can rapidly decrease blood volume and result in low blood pressure.
- Anemia: A reduced number of red blood cells or a lower hemoglobin level can lead to anemia, which can result in low blood pressure because there is less oxygen-carrying capacity in the blood.
- Postural or orthostatic hypotension: Some people experience a drop in blood pressure when they stand up from a sitting or lying position, known as orthostatic or postural hypotension. This can be caused by dehydration, certain medications, or disorders of the autonomic nervous system.
- Neurological conditions: Conditions that affect the autonomic nervous system, such as Parkinson’s disease and multiple system atrophy, can disrupt the body’s ability to regulate blood pressure, leading to low blood pressure.
- Infections: Severe infections, like sepsis, can cause low blood pressure as the body responds to the infection by dilating blood vessels and decreasing blood pressure.
- Allergic reactions: Anaphylaxis, a severe allergic reaction, can cause a sudden drop in blood pressure due to the release of histamines and other substances that dilate blood vessels.
It’s important to note that sometimes, low blood pressure may not have an identifiable cause and may be considered essential or idiopathic. If you or someone you know experiences persistently low blood pressure, especially if it is accompanied by symptoms like dizziness, fainting, fatigue, or confusion, it’s essential to consult a healthcare professional for a proper evaluation and diagnosis. Treatment will depend on the underlying cause of the low blood pressure.