When Is Low Blood Pressure Too Low? Managing Hypotension Symptoms and Causes

Defining Low Blood Pressure

Blood pressure is the force exerted against the walls of the arteries as blood flows through the circulatory system. It is recorded as two numbers - the systolic pressure (the pressure as the heart contracts) over the diastolic pressure (the pressure as the heart relaxes between beats).

Normal blood pressure ranges are:

• Normal: Less than 120/80 mm Hg
• Elevated: 120-129/Less than 80 mm Hg
• Stage 1 Hypertension: 130-139/80-89 mm Hg
• Stage 2 Hypertension: 140/90 mm Hg or higher

Low blood pressure, also called hypotension, is typically classified as:

• Systolic reading lower than 90 mm Hg
• Diastolic reading lower than 60 mm Hg

However, what is considered low can vary from person to person. For some, consistent readings below 110/70 mm Hg may be lower than normal.

Symptoms of Low Blood Pressure

In many cases, low blood pressure does not cause any symptoms. People can have hypotension for years without realizing it. But for some, low readings can result in noticeable symptoms including:

• Dizziness - Feeling lightheaded and dizzy is a common symptom of low blood pressure. Decreased blood flow to the brain can lead to temporary dizziness when standing up quickly from a seated position.
• Fainting (syncope) - In more severe cases, low blood pressure can cause people to briefly lose consciousness and faint. This happens when the brain experiences a temporary lack of oxygenated blood flow.
• Lethargy and weakness - Chronic fatigue and overall body weakness can occur with extended periods of hypotension.
• Blurred vision - Low blood pressure can impair blood delivery to the eyes, resulting in temporary vision changes or blurriness.
• Nausea - Some individuals experience nausea and appetite loss resulting from low blood pressure.
• Confusion - Decreased blood circulation to the brain can also lead to temporary confusion, difficulty concentrating, and mood changes.
• Depression - Persistent hypotension can disrupt hormone levels and lead to feelings of depression and hopelessness.

Typically, the lower your blood pressure readings, the more pronounced and disruptive your symptoms may be. Milder drops may only cause occasional dizziness, while severe hypotension can result in fainting spells and significant fatigue.

Causes of Low Blood Pressure

There are many potential causes of low blood pressure, ranging from normal lifestyle factors to serious medical conditions. Understanding the underlying cause can help guide treatment and management approaches.

Common Causes

Some of the most common causes of temporary or consistent low blood pressure include:

• Dehydration - Being dehydrated from fluid losses through sweat, vomiting, diarrhea or other means can lower blood volume and pressure. Drinking plenty of fluids can help.
• Hypoglycemia - Low blood sugar levels can trigger a temporary drop in blood pressure. Eating regular balanced meals can prevent this response.
• Nutritional deficiencies - Lacking key nutrients like vitamin B12, iron and folic acid may decrease blood pressure.
• Pregnancy - Blood pressure naturally tends to be lower during pregnancy.
• Heart conditions - Some heart issues like bradycardia can lower pressure. Anemia and heart valve disorders can too.
• Endocrine problems - Thyroid disorders, Addison's disease, and other conditions involving hormones can affect blood pressure.
• Medications - Certain prescription medications like diuretics, beta-blockers, ACE inhibitors and others can lower blood pressure as a side effect.
• Postural hypotension - Also called orthostatic hypotension, this refers to a temporary pressure drop that occurs when moving from sitting to standing. It's caused by a delay in the body's mechanisms for adjusting pressure.

Serious Causes

While many causes of low blood pressure are benign, hypotension can also signal potentially serious underlying conditions like:

• Sepsis - This systemic blood infection disrupts blood flow and can result in extremely low pressure.
• Shock - Shock refers to a dangerous drop in blood flow to organs and tissues that can result from injury, blood loss or infection.
• Heart failure - Chronic heart failure inhibits the heart's pumping ability, potentially decreasing blood pressure.
• Pulmonary embolism - A blood clot in the lungs obstructs blood flow and lowers pressure.
• Internal bleeding - Bleeding from trauma, gastrointestinal issues or ruptured blood vessels depletes circulating volume.

Additional serious causes can include severe allergic reactions (anaphylaxis), adrenal crisis, blood infections, and complications of diabetes among others. Low blood pressure in these situations requires urgent medical attention.

When Is Low Blood Pressure Concerning?

For most healthy individuals, a single low reading is not necessarily concerning on its own. Blood pressure can vary and be impacted by factors like stress, time of day, activity level, and diet.

However, consistently low pressure or a significant, prolonged drop may be more worrisome. Potential warning signs to seek medical evaluation include:

• Systolic pressure below 90 mm Hg for extended periods
• Pressure drops resulting in lightheadedness, dizziness, or fainting
• Inability to concentrate, confusion, or blurred vision
• Fatigue, weakness, chest pain, or shortness of breath
• Associated fever, nausea, or pain

Sudden crashes in blood pressure can also be dangerous, especially in older individuals. Acute drops of 20 mm Hg or more in systolic pressure can deprive the brain and organs of oxygen, potentially resulting in health emergencies.

Additionally, those with known cardiovascular disease and diabetes may require closer blood pressure monitoring. Their risk of syncope and resulting injuries from fainting due to low pressure may be higher.

Treating Chronic Low Blood Pressure

If low blood pressure is confirmed with multiple readings below normal, possible treatment approaches may include:

• Increasing fluid and salt intake - Staying well hydrated and getting enough dietary sodium can help maintain blood volume.
• Raising head of bed - Elevating the head while sleeping avoids pressure drops associated with postural hypotension.
• Wearing compression stockings - Compression garments promote blood flow and may lessen pressure drops when standing.
• Medications - Drugs like fludrocortisone, midodrine, ephedrine, or vasopressors may be used to raise pressure in some instances.
• Treating underlying conditions - Any illnesses causing low pressure will also need to be managed, like thyroid disorders or diabetes.

Doctors may also recommend adjusting the dose of any medications that may be provoking hypotension. Slow position changes, exercise, avoiding hot environments, and implementing sensible dietary changes can also help reduce symptoms.

Responding to Sudden Blood Pressure Drops

Sudden crashes in blood pressure that result in acute symptoms like dizziness and fainting require prompt action. Recommended first aid steps include:

• Laying the person flat and elevating their legs above heart level. This helps return blood flow to the brain.
• Loosen any tight clothing and ensure they can breathe comfortably.
• Check for injuries if they fainted or fell.
• Give them sips of water once they are alert.
• Have them stay seated for a bit before trying to stand again.

Calling emergency services is advised if they do not recover quickly, fainted without a clear trigger, experience chest pain or shortness of breath, or have known heart disease or diabetes. Repeat episodes of sudden hypotension should be evaluated by a doctor.

Preventing Low Blood Pressure

Proactive steps individuals can take to help avoid drops in blood pressure include:

• Drinking plenty of water and eating a diet higher in sodium.
• Rising slowly after meals, showers, and from reclined positions.
• Avoiding excess alcohol which can dilate blood vessels.
• Wearing compression stockings if prone to postural hypotension.
• Engaging in regular exercise which can help improve overall circulation.
• Limiting time spent in hot baths or saunas which can deplete body fluids.
• Checking with your doctor before using new medications or supplements than can affect blood pressure.

People with known cardiovascular conditions or frequent episodes of low blood pressure may benefit from more frequent at-home monitoring. This can identify concerning patterns early.

Takeaways on Low Blood Pressure

While not always a cause for concern, consistently low blood pressure or abrupt decreases can produce troublesome symptoms and signal underlying health issues. Being attuned to your body's signals, preventing dehydration and overheating, and getting evaluated for sudden drops can help preserve your well-being.

Report any episodes of lightheadedness, fainting, or significant fatigue to your doctor. With an accurate diagnosis, proper treatment approaches can help manage hypotension and keep your blood pressure stable.

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.