Low blood pressure, or hypotension, happens when the force of blood pushing against the artery walls is too low, generally considered below 90/60 mm Hg. It can be caused by many factors including dehydration, certain medications, heart conditions, pregnancy, hormonal imbalances, blood loss, severe infections, and nutritional deficiencies. In some cases, it may also be due to specific types of hypotension such as orthostatic hypotension (a sudden drop on standing up), postprandial hypotension (after eating), or neurally mediated hypotension (after standing for long periods). Low blood pressure may cause symptoms like dizziness and fainting, or it might have no noticeable symptoms at all. Identifying the underlying cause is important for proper treatment and care.
Common Causes of Low Blood Pressure
- Dehydration : Loss of fluids reduces blood volume, lowering blood pressure.
- Medications : Blood pressure drugs, diuretics, antidepressants, Parkinson’s disease medications, and erectile dysfunction drugs can lower blood pressure.
- Heart Conditions : Heart failure, heart valve problems, slow heart rate, or heart attack.
- Hormonal Issues : Disorders like Addison’s disease, low thyroid hormone levels, or low blood sugar.
- Blood Loss : Significant bleeding from injury or internal sources reduces blood volume.
- Nutritional Deficiencies : Lack of vitamin B12, folate, or iron resulting in anemia.
- Pregnancy : Blood vessels expand, lowering blood pressure especially in the first 24 weeks.
- Severe Infection or Allergic Reactions : Can cause dangerous drops in blood pressure (septic or anaphylactic shock).
Types of Low Blood Pressure
- Orthostatic Hypotension : Drop in blood pressure when standing up quickly, often due to dehydration or medication.
- Postprandial Hypotension : Blood pressure drops 1-2 hours after eating.
- Neurally Mediated Hypotension : Triggered by prolonged standing, common in children and young adults.
If low blood pressure causes symptoms or complications, or if it follows a serious event like bleeding or infection, medical evaluation is important.
If seeking personalized advice, it is best to consult a healthcare provider who can diagnose and treat the underlying cause.
