What Causes Low Blood Pressure?
There are several factors that can cause low blood pressure:
Dehydration
Dehydration is one of the most common causes of low blood pressure. When the body loses more fluid than it takes in, the volume of blood circulating decreases which leads to a drop in blood pressure. Dehydration can occur due to insufficient fluid intake, excessive sweating, vomiting, diarrhea etc.
Prolonged Bed Rest
Prolonged periods of bed rest or inactivity can cause blood pressure to drop. This is due to muscles in the legs and abdomen not contracting to support circulation. Elderly or hospitalized individuals staying in bed for long periods are at risk of developing hypotension.
Pregnancy
During pregnancy, the expansion of the circulatory system and increase in hormones can lead to a drop in blood pressure. Blood pressure usually returns to normal post delivery.
Heart Problems
Certain heart conditions like extremely low heart rate (bradycardia), heart valve disorders, heart attack or heart failure can impair the heart's ability to pump blood effectively, leading to low blood pressure.
Endocrine Problems
Endocrine disorders like hypothyroidism, adrenal insufficiency, low blood sugar (hypoglycemia) and diabetes can cause low blood pressure. Malfunction in the endocrine glands results in imbalance of hormones that regulate blood pressure.
Nutritional Deficiencies
Deficiency of vitamins like B12, folate and minerals like iron can affect the production of red blood cells leading to anemia and subsequent drop in blood pressure.
Medications
Certain medications like diuretics, vasodilators, antidepressants, heart medications, Parkinson's medications etc can cause drug induced hypotension.
Sepsis
Sepsis, a bodywide inflammatory response to infection can cause extremely low blood pressure leading to shock. This occurs due to large amounts of inflammatory chemicals released in the blood during sepsis.
Anaphylaxis
Anaphylaxis or severe allergic reaction can trigger dangerously low blood pressure. Chemicals like histamines released during anaphylaxis can cause blood vessels to dilate rapidly leading to hypotension.
Neurally Mediated Hypotension
This disorder occurs when the automatic nervous system does not respond appropriately to stimuli. Standing up after sitting or lying down signals the body to compensate for blood pressure and heart rate changes. But in neurally mediated hypotension, this mechanism does not work effectively.
Symptoms of Low Blood Pressure
Symptoms of hypotension can vary from person to person. Some people with milder forms may not experience any symptoms. Symptoms tend to be more pronounced when blood pressure drops suddenly rather than over time. Here are some common symptoms of low BP:
Dizziness or Lightheadedness
Low blood flow to the brain can result in dizziness or lightheaded feeling especially when standing up from sitting or lying down. This is one of the most common symptoms of hypotension.
Fainting (Syncope)
A severe drop in blood pressure can cause temporary loss of consciousness or fainting due to the brain not receiving enough oxygenated blood.
Lethargy and Fatigue
Generalized weakness and lack of energy can occur as tissues do not receive enough oxygen and nutrients due to low blood pressure.
Blurred Vision
Eyes may not receive sufficient blood supply causing temporary blurring of vision.
Nausea
Low blood flow to the gastro-intestinal tract can induce a nauseating feeling.
Cold, Clammy Skin
Restricted blood flow causes the skin to become cool and clammy to touch.
Rapid, Shallow Breathing
The body tries to compensate for low BP by speeding up breathing.
Irregular Heartbeat
Hypotension may cause heart palpitations or irregular heartbeat.
Depression and Anxiety
Chronic low blood pressure can induce symptoms of depression and anxiety in some people.
Erectile Dysfunction
Insufficient blood supply may also cause erection problems in men.
Risk Factors for Low Blood Pressure
Certain factors that can increase your risk of developing hypotension include:
Age
Blood pressure tends to drop with age due to reduced heart function and stiffening of blood vessels.
Female Gender
Younger women are more likely to have lower BP than men of comparable age due to smaller hearts and blood vessels and effects of female hormones.
Pregnancy
Blood pressure starts dropping in the first trimester and tends to reach its lowest in mid-pregnancy before returning to normal around term.
Heart Disease
People with certain heart conditions like heart valve problems, heart failure etc are more predisposed to low blood pressure.
Endocrine Problems
Thyroid disorders, adrenal insufficiency, low blood sugar states can increase chances of developing hypotension.
Parkinson's Disease
Some Parkinson's medications can frequently cause pressure drops.
Certain Medications
Drugs like diuretics, beta-blockers, calcium channel blockers etc can lower blood pressure.
Neurally Mediated Hypotension
People with this disorder have dysfunctional automatic nervous systems that are unable to regulate blood pressure.
Excessive Alcohol
Drinking too much alcohol can interact with blood pressure medications or cause dehydration leading to hypotension.
Diagnosing Low Blood Pressure
If you experience symptoms like dizziness, fainting or fatigue, your doctor will take a detailed history asking about your symptoms, medical conditions, family history and medications. Your doctor will also perform a physical exam checking pulse, heart, lungs and blood pressure. They may diagnose hypotension if your blood pressure is lower than 90/60 mmHg.
Your doctor may recommend these tests for further evaluation:
Blood Tests
Blood count, electrolytes, thyroid and adrenal function are tested to check for underlying conditions causing low BP.
Electrocardiogram (ECG)
ECG analyzes heart rhythm and detects any abnormalities.
Echocardiogram
This ultrasound of the heart checks pumping function and detects any problems.
Stress Test
Exercise stress test monitors heart rate and BP response to exertion.
Tilt Table Test
This assesses how your body controls blood pressure in response to changes in position.
Treating Low Blood Pressure
Treatment depends on the underlying cause and may include:
Increasing Fluid and Salt Intake
Consuming fluids and adding extra salt to meals helps increase blood volume and BP. Broths and soups are good options.
Raising the Head
Elevating the head while sleeping allows blood to flow more easily to the brain, improving symptoms.
Wearing Compression Stockings
Compression stockings improve venous blood flow and prevent blood from pooling in the legs.
Medications
Drugs like fludrocortisone, midodrine, beta-blockers, vasopressors etc may be prescribed if lifestyle measures fail.
Treating Underlying Conditions
Treatment of contributory illnesses like heart disease, endocrine disorders etc is required.
Preventing Low Blood Pressure
You can take these precautions to avoid drops in blood pressure:
Stay Hydrated
Drink adequate fluids regularly to prevent dehydration.
Increase Salt Intake
Boost salt consumption through saltier foods or supplements to maintain fluid balance.
Wear Compression Stockings
Compression stockings prevent blood pooling in legs and regulate blood flow.
Avoid Alcohol
Limit alcohol intake as it can interact with BP medications or worsen dehydration.
Take Smaller Meals
Eating smaller portions several times a day prevents large post-meal blood pressure drops.
Exercise Caution When Standing
Rise slowly from sitting or lying down to avoid sudden BP drops.
Avoid Hot Temperatures
Heat causes vasodilation and increases risk of low BP and fainting.
Review Medications
Consult your doctor regarding medication interactions or alternatives to drugs affecting BP.
When to See a Doctor
Consult your doctor if you experience any of these:
Frequent drops in BP causing dizziness or fainting
Lightheadedness or blurred vision impairing daily activities
Unexplained fatigue, confusion or depression
Symptoms that persist despite self-treatment
Problems with medications causing recurrent hypotension
Prompt medical care is vital for those with dangerously low BP or symptoms like chest pain, difficulty breathing, loss of consciousness etc. Seek emergency care if blood pressure drops excessively after meals, injuries or illnesses.
Conclusion
Low blood pressure or hypotension is typically diagnosed when BP levels are below 90/60 mmHg. Though not always serious, chronic low BP or sudden drops can produce troubling symptoms. Orthostatic hypotension, pregnancy, heart disease, endocrine disorders, medications and dehydration are some contributory factors. Adding salt, drinking more fluids, using compression stockings and drugs may help rectify hypotension. Preventative care like staying hydrated, avoiding alcohol and reviewing medicines is recommended. Seek medical assistance promptly for severe, recurrent or unresponsive episodes of low BP.
FAQs
What are the symptoms of low blood pressure?
Common symptoms of low BP include dizziness, lightheadedness, fainting, fatigue, nausea, blurred vision, pale skin, increased heart rate etc. But some people with mild hypotension may not have any symptoms.
What causes chronic low blood pressure?
Some common causes of chronically low BP are heart conditions, endocrine disorders like hypothyroidism or Addison's disease, nutritional deficiencies, sepsis, medications, pregnancy and neurally mediated hypotension.
Is low blood pressure dangerous?
Milder forms of low BP may not be concerning. But consistently low BP below 90/60 mmHg can deprive organs of oxygen and nutrients. Sudden significant drops can lead to life-threatening health issues.
How can I raise my low BP quickly?
To raise BP quickly, lie down and elevate the legs, drink 2-3 glasses of water, consume something salty like broth or soup, wear compression stockings and avoid standing up suddenly.
When should I see a doctor for hypotension?
Consult a doctor if you experience frequent drops in BP causing fainting or falls, lightheadedness affecting daily activities, chronic fatigue not alleviated by rest, or symptoms that persist despite self-treatment.
Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.
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