Diastolic blood pressure below 60 mmHg, especially when your systolic (top number) remains normal, is considered low and can cause real symptoms. Raising it typically involves increasing your blood volume through fluids and salt, improving vascular tone, and in some cases working with a doctor on medication. The right approach depends on what’s causing the drop in the first place.
What Counts as Low Diastolic Pressure
The 2025 AHA/ACC guidelines define normal blood pressure as below 120/80 mmHg, but they don’t set an official lower limit for diastolic readings. In clinical research, a diastolic reading below 60 mmHg with a systolic reading at or above 100 mmHg is classified as isolated diastolic hypotension. That distinction matters because it separates people whose bottom number alone is too low from those who have generally low blood pressure across both numbers.
A diastolic reading in the 60s is usually fine if you feel normal. The concern starts when readings consistently dip below 60 and you begin noticing symptoms like dizziness, fatigue, blurred vision, trouble concentrating, or an upset stomach. Even a shift of just 20 mmHg from your usual reading can be enough to make you feel lightheaded or faint. Research published in the AHA’s journal Hypertension found that isolated diastolic hypotension is an independent risk factor for heart failure in older adults, so persistently low readings are worth addressing rather than ignoring.
Why Diastolic Pressure Drops
Your diastolic number reflects the pressure in your arteries between heartbeats, when your heart is refilling with blood. It depends heavily on two things: how much blood is circulating in your body and how much resistance your blood vessels provide. When either drops, diastolic pressure falls.
Dehydration is one of the most common and fixable causes. Not drinking enough fluid shrinks your blood volume, which directly lowers pressure. Certain medications, particularly those prescribed for high blood pressure, heart conditions, or depression, can push diastolic readings too low as a side effect. Prolonged bed rest, standing up too quickly, large meals, and hot environments all contribute as well. In older adults, arterial stiffening can widen the gap between systolic and diastolic readings, pulling the bottom number down even as the top number stays the same or rises.
Increase Your Fluid Intake
The simplest and most immediate way to raise diastolic pressure is to drink more fluids. Low blood volume is a direct cause of low pressure, and rehydrating expands that volume. The National Academies of Science, Engineering and Medicine recommends about 125 ounces (3.7 liters) of total fluid per day for men and 91 ounces (2.7 liters) for women. That includes water from food, but most people fall short of these targets.
If you’re prone to low diastolic readings, start your day with a full glass of water before coffee or tea. Drink consistently throughout the day rather than catching up in the evening. During hot weather, exercise, or illness involving vomiting or diarrhea, you’ll need more. Beverages with electrolytes can help your body retain the fluid rather than just passing it through.
Add More Salt (When Appropriate)
For most health conditions, doctors recommend limiting sodium. Low diastolic pressure is one of the exceptions. Sodium helps your body hold onto water, which increases blood volume and raises pressure. If your doctor confirms that your blood pressure is too low and you don’t have heart failure or kidney disease, adding salt to your diet is a straightforward intervention.
This doesn’t require dramatic changes. Salting your meals a bit more generously, snacking on salted nuts or olives, or drinking broth can make a noticeable difference. Some people keep electrolyte tablets or oral rehydration solutions on hand for days when symptoms are worse. The goal isn’t to overdo it, just to stop actively restricting salt if that’s been your habit.
Adjust How You Eat and Move
Large meals pull blood toward your digestive system and away from your core circulation, which can drop diastolic pressure for one to two hours after eating. Switching to smaller, more frequent meals reduces that effect. Cutting back on refined carbohydrates at meals can also help, since they tend to cause a larger post-meal blood pressure dip than protein or fat.
Position changes matter too. If you feel lightheaded when standing, get up slowly, especially in the morning. Sitting on the edge of the bed for 30 seconds before standing gives your cardiovascular system time to adjust. Crossing your legs while sitting and tensing your thigh muscles when you stand are small physical maneuvers that squeeze blood back toward your heart and temporarily raise pressure.
Caffeine can provide a short-term boost to blood pressure. A cup of coffee or tea before meals or before periods when you’ll be on your feet may reduce symptoms. The effect is temporary, usually lasting an hour or two, but it can be useful as part of a broader strategy.
Compression Garments
Compression stockings, particularly knee-high or thigh-high versions, work by preventing blood from pooling in your lower legs. They’re most helpful if your low diastolic pressure is related to standing for long periods or orthostatic changes (feeling worse when upright). Graduated compression stockings apply the most pressure at the ankle and gradually decrease toward the thigh, which promotes blood flow back to the heart.
Research on whether compression stockings directly raise diastolic readings is mixed. One study on healthy women found no significant change in diastolic pressure from wearing them. However, they’re widely recommended by cardiologists for people with orthostatic hypotension because they reduce the symptom burden, particularly dizziness and fatigue on standing. If pooling in the legs is contributing to your low readings, they’re worth trying.
When Medication Becomes Necessary
If lifestyle changes aren’t enough, two types of medication are commonly prescribed for chronically low blood pressure. One works by increasing blood volume, helping your body retain more salt and water. The other works by tightening blood vessels so they don’t expand as easily, which directly raises the pressure within them. Both are typically reserved for people with persistent symptoms that interfere with daily life, particularly those who experience frequent dizziness or fainting when standing.
It’s also worth reviewing any medications you’re already taking. Blood pressure drugs, certain antidepressants, alpha blockers prescribed for prostate issues, and some Parkinson’s medications can all lower diastolic pressure as a side effect. Adjusting the dose or timing of these medications, under a doctor’s guidance, sometimes resolves the problem without adding anything new.
What You Can’t Selectively Control
One frustration with low diastolic pressure is that there’s no reliable way to raise the bottom number without also affecting the top number. Fluids, salt, and medications raise overall blood pressure. If your systolic reading is already normal or slightly elevated, this creates a balancing act. That’s why isolated diastolic hypotension in older adults, where systolic pressure tends to be higher, requires careful monitoring rather than aggressive treatment.
Tracking your readings at home with a validated blood pressure monitor gives you and your doctor better data than occasional office visits. Measure at the same time each day, sitting quietly for five minutes first, with your arm supported at heart level. Record both numbers along with any symptoms. Patterns over weeks are far more useful than any single reading.