Blood pressure is generally considered too low when it drops below 90/60 mmHg, though there’s no universally fixed cutoff. The 2025 guidelines from the American Heart Association define normal blood pressure as below 120/80 mmHg but don’t set an official floor. What matters more than the number itself is whether you’re experiencing symptoms. Some people walk around with a systolic pressure in the 80s and feel perfectly fine, while others get dizzy at 95. Low blood pressure, called hypotension, only becomes a medical concern when it starts affecting how your body functions.
How Low Blood Pressure Feels
The most common symptom is dizziness or lightheadedness, especially when you stand up quickly. You might also notice blurred or fading vision, fatigue, trouble concentrating, or nausea. Some people feel sluggish or weak without an obvious reason. In more pronounced cases, you may faint or come close to it.
When blood pressure drops dangerously low, it can lead to shock. The signs are distinct and hard to miss: cold, clammy skin, rapid shallow breathing, a weak and fast pulse, confusion (particularly in older adults), and visibly pale or bluish skin, especially around the lips or fingernails. Shock is a medical emergency that requires immediate help.
Why Blood Pressure Drops
Dehydration is one of the most common triggers. When your body doesn’t have enough fluid, blood volume falls and pressure drops with it. This is why low blood pressure often shows up during hot weather, after exercise, or during an illness that causes vomiting or diarrhea.
Medications are another frequent cause. Drugs prescribed for high blood pressure, heart conditions, or depression can sometimes push pressure lower than intended. Pregnancy naturally lowers blood pressure in the first and second trimesters because the circulatory system expands rapidly. Blood loss, severe infections, heart problems, and hormonal conditions like adrenal insufficiency can all play a role too.
Orthostatic Hypotension
This is the type you feel when you stand up and the room briefly spins. It’s diagnosed when your systolic (top number) pressure drops by 20 mmHg or more, or your diastolic (bottom number) drops by 10 mmHg or more, within a few minutes of standing. Lightheadedness or dizziness on standing counts as abnormal even if the numbers don’t hit those thresholds exactly.
Orthostatic hypotension is especially common in older adults and in people taking blood pressure medications. It happens because gravity pulls blood toward your legs when you stand, and your body’s reflexes don’t compensate quickly enough. Over time, this can increase the risk of falls and injuries, which is why it’s worth mentioning to a healthcare provider if it happens regularly.
Postprandial Hypotension
Some people experience a significant blood pressure drop after eating. This is called postprandial hypotension, and it typically involves a systolic drop of about 20 mmHg within 30 to 60 minutes of a meal, though it can occur up to two hours afterward. It’s most common in older adults and can cause the same dizziness, fatigue, and fainting risk as other forms of low blood pressure. Large, carbohydrate-heavy meals tend to make it worse because more blood gets directed to the digestive system.
How It’s Diagnosed
A standard blood pressure reading is the starting point. If your readings are consistently low and you’re having symptoms, your provider will look for an underlying cause. Basic blood work can reveal dehydration, anemia, thyroid problems, or blood sugar issues. An electrocardiogram checks for heart rhythm problems.
If you’ve been fainting without a clear explanation, you may be referred for a tilt table test. During this test, you lie flat on a table that tilts you upright while monitors track your blood pressure, heart rate, and rhythm. The goal is to reproduce your symptoms in a controlled setting. A positive result means your body responded abnormally to the position change, with a large drop in blood pressure or a large spike in heart rate. This test helps distinguish between conditions like orthostatic hypotension, vasovagal syncope (fainting triggered by stress or certain stimuli), and postural orthostatic tachycardia syndrome, where your heart rate increases excessively upon standing.
Managing Low Blood Pressure
For many people, simple lifestyle changes make a meaningful difference. Increasing fluid intake is one of the most effective steps. A general recommendation is 60 to 100 ounces of fluid per day, though individual needs vary. Adding salt to your diet can also help raise blood volume and pressure. Johns Hopkins Medicine suggests 3 to 5 grams of salt daily for people with symptomatic low blood pressure, which is notably higher than the amount typically recommended for the general population. If you’ve been told to limit sodium for another condition, this is something to discuss with your provider before changing.
Other practical strategies include standing up slowly, especially first thing in the morning. Crossing your legs or squeezing your thigh muscles before standing can help push blood back toward your heart. Eating smaller, more frequent meals rather than large ones reduces the risk of postprandial drops. Compression stockings, which apply gentle pressure to your lower legs, can prevent blood from pooling there.
If a medication is causing your low blood pressure, adjusting the dose or switching to a different drug often resolves the problem. When an underlying condition like a heart issue or hormonal deficiency is responsible, treating that condition typically brings blood pressure back into a comfortable range.
When Low Blood Pressure Is Actually Normal
Physically active people and younger adults, particularly women, often have blood pressure readings that would technically qualify as “low” without any symptoms or health risk. A reading of 90/60 in a fit 25-year-old who feels great is not a problem. Athletes frequently have lower resting blood pressure because their hearts pump more efficiently. In these cases, low blood pressure is a sign of good cardiovascular health, not something that needs treatment. The distinction always comes back to symptoms: if your blood pressure is low and you feel fine, it’s almost certainly not a concern.