Low Blood Pressure (Hypotension): Symptoms, Causes and When It Needs Attention

What it involves

MedlinePlus explains that low blood pressure, or hypotension, occurs when blood pressure is below normal, meaning the heart, brain and other parts of the body may not get enough blood. In adults it gives normal as between 90/60 and 120/80 mmHg.

Who this is for

• Patients who feel dizzy or lightheaded when they stand up, especially after sitting or lying down
• Patients who have fainted or nearly fainted, or who have blurry vision with a low reading
• Patients taking blood pressure, heart, antidepressant or water-pill medicines who feel faint
• Older adults who have had a fall and want to know whether blood pressure played a part

What to expect

• Questions about your usual blood pressure, your medicines, how well you are eating and drinking and any recent illness
• Blood pressure checked sitting and standing, along with pulse and other vital signs
• An in-office EKG at the Loxahatchee and West Palm Beach offices if a heart rhythm cause is possible, and blood work
• A plan that may adjust a medicine, address fluids or send you for a cardiology or nerve evaluation

A number is not the whole story

MedlinePlus notes that blood pressure varies from one person to another and over time, and that a drop of as little as 20 mmHg can cause problems for some people. It also says a lower-than-normal reading in a healthy person that causes no symptoms often needs no treatment. So the reading alone does not decide it; what matters is whether you feel unwell. The blood pressure readings guide explains how to read a measurement and what the two numbers mean.

Symptoms to take seriously

The encyclopedia lists blurry vision, confusion, dizziness, fainting, lightheadedness, nausea or vomiting, sleepiness and weakness as symptoms of low blood pressure. If you feel symptoms, it advises sitting or lying down right away and raising the feet above heart level. Dizziness has many sources, and the dizziness guide explains how a provider separates them, while the fainting guide covers what to do after a blackout. Do not drive if you feel faint.

Standing up too fast and other types

MedlinePlus describes several types. Orthostatic hypotension is a drop in pressure when you shift from lying down to standing, which usually lasts only seconds or minutes; when it occurs after eating, it is called postprandial and most often affects older adults, people with high blood pressure and people with Parkinson disease. Neurally mediated hypotension most often affects young adults and children and can occur after standing a long time. Severe hypotension, or shock, can follow sudden blood loss, severe infection, a heart attack or a severe allergic reaction, and is an emergency.

Causes on the list

Medicines are a frequent cause: MedlinePlus names alcohol, anti-anxiety medicines, certain antidepressants, diuretics, heart medicines including those for high blood pressure and coronary heart disease, medicines used for surgery and painkillers. Other causes include nerve damage from diabetes or other disorders, heart rhythm changes, dehydration and heart failure. If blood pressure medicine is the possible cause, the hypertension management page explains how that treatment is followed. Do not stop a medicine without first speaking to your provider.

Tests and treatment

MedlinePlus says your provider will examine you to find the cause and that tests may include a basic metabolic panel, blood count, urinalysis, an electrocardiogram and x-rays. This practice offers blood work and in-office EKG at Loxahatchee and West Palm Beach, described on the EKG page, and the basic metabolic panel guide explains one common blood test. Treatment depends on the cause: a medicine change, more fluids for dehydration, compression stockings, or avoiding triggers such as standing a long time.

Why falls matter

The encyclopedia warns that falls caused by low blood pressure in older adults can lead to a broken hip or spine fracture, injuries that can reduce health and the ability to move about. It also says sudden, severe drops starve the body of oxygen and can damage the heart, brain and other organs. That is why an older adult who feels faint on standing deserves an earlier visit rather than a wait-and-see approach. It also says low blood pressure can usually be treated successfully.

Sources

• MedlinePlus — Low blood pressure
• MedlinePlus — Low Blood Pressure (health topic)