About half of adults in the United States have high blood pressure (hypertension), which can increase the risk of serious medical issues that affect the heart, kidney, brain, and eyes. Those with high blood pressure get treatment and make lifestyle changes to help lower it. While lower blood pressure may be the goal for those with high blood pressure, having abnormally low blood pressure can also lead to health issues. Mildly low blood pressure may cause no problems for some, but significantly low blood pressure, and sudden changes in blood pressure, can be a sign of a serious medical problem. In this article, I’ll discuss what low diastolic blood pressure is and symptoms of the condition. I’ll explain causes of low diastolic blood pressure and causes of general low blood pressure. I’ll talk about how low diastolic blood pressure can be treated. Finally, I’ll explore low diastolic blood pressure complications.

What is Low Diastolic Blood Pressure

Blood pressure is the force of blood pushing against the walls of your arteries. It’s measured with two numbers: systolic pressure and diastolic pressure.

• Systolic blood pressure: Systolic blood pressure measures pressure when your heart beats and pushes blood from the heart to the rest of the body.

• Diastolic blood pressure: Diastolic blood pressure measures pressure in blood vessels between heartbeats, when your heart relaxes and its chambers fill with blood.

Systolic and diastolic blood pressure are measured in millimeters of mercury (mm HG) and written as a fraction, with the systolic as the upper number and the diastolic as the bottom number. A normal blood pressure for adults 120/80 mm HG. Generally, blood pressure is considered to be low, called hypotension, when it is typically lower than 90/60 mm HG. Typically, closer attention is paid to the systolic number, however, a recent study has shown that focusing on the diastolic blood pressure is just as important. The study coined the term “isolated diastolic hypotension,” which means having a normal systolic pressure and a low diastolic pressure (lower than 60 mm Hg). Those with low diastolic pressure have low coronary artery pressure, which causes a lack of blood and oxygen in the heart. This can weaken the heart over time and lead to serious medical issues, such as heart failure.

Symptoms of Low Diastolic Blood Pressure

Low diastolic blood pressure may cause the following symptoms:

• Lightheadedness
• Confusion
• Tiredness
• Weakness
• Falls

Low diastolic pressure may also cause symptoms of heart failure, including chest pain, shortness of breath, heart palpitations, or swelling of feet.

Symptoms of low diastolic blood pressure and low systolic blood pressure

The following are symptoms of low diastolic blood pressure and low systolic blood pressure (hypotension):

• Dizziness or lightheadedness
• Confusion
• Blurred or fading vision
• Fatigue
• Nausea
• Fainting

If blood pressure drops severely low, it can lead to shock, which is a state where not enough blood flows through the body. Signs of shock include rapid breathing, weak, rapid pulse, or cold, sweaty, or blue skin. If you experience these symptoms, seek medical attention immediately.

Cause of Low Diastolic Blood Pressure

Pregnancy and heart conditions, such as low heart rate, heart valve disorders, and heart failure, can lead to low diastolic blood pressure. Aging is another risk factor, as well. As you age, your vessels become stiff, which can prevent enough blood and oxygen from flowing back into the heart. Low diastolic blood pressure can also be caused by medications and lifestyle factors.

Medications 

Medications, especially ones that are prescribed for hypertension, are common causes of low diastolic blood pressure. Alpha blockers (central acting anti-hypertensive agents) can lower your diastolic blood pressure more than your systolic blood pressure. Other medications that can lead to low diastolic blood pressure include erectile dysfunction drugs, tricyclic antidepressants, Parkinson’s disease drugs, beta blockers, and diuretics.

Lifestyle

Low diastolic blood pressure can also be caused by diet, including not drinking enough water, which lowers the overall blood volume.

Cause of General Low Blood Pressure

While blood pressure may vary throughout the day, certain medications, medical conditions, and lifestyle factors can cause persistently low blood pressure.

Medications 

Taking the following medication can lead to low blood pressure:

• Alpha blockers
• Beta blockers
• Diuretics
• Certain types of antidepressants
• Erectile dysfunction medication
• Parkinson’s disease medication

Medical conditions 

There are various medical conditions that can cause low pressure, including:

• Pregnancy
• Anemia
• Heart conditions, including low heart rate (bradycardia), heart attack, and heart failure
• Thyroid and adrenal issues
• Severe infections
• Severe allergic reactions
• Bleeding

Lifestyle

Lack of vitamin B12, iron, and folate in your diet can lead to low blood pressure, since these nutrients help your body produce enough red blood cells. Having an insufficient amount of red blood cells can lead to low blood pressure.

Treatment of Low Diastolic Blood Pressure

Treatment of low diastolic blood pressure depends on the primary cause of the hypotension. If you have low blood pressure, you should see a medical professional right away. They will perform an assessment, determine the cause of your low blood pressure, and recommend a treatment plan.

Treating isolated low diastolic blood pressure 

If low diastolic blood pressure is caused by medication, your doctor may adjust your dosage or change your prescription. They will address any contributing lifestyle factors and also evaluate for serious underlying causes of your low blood pressure. Lifestyle changes can also help, including getting exercise, maintaining a healthy weight, and refraining from smoking.

Treating general low blood pressure

Low blood pressure that is mild and doesn’t cause symptoms often doesn’t need treatment. But for those with symptoms, treatment will be based on the cause if it’s identifiable. If you’re taking medication that’s causing low blood pressure, you may have to change medication or adjust dosage based on what your doctor determines. If the cause of low blood pressure is unclear and your doctor decides that raising your blood pressure should be your objective, then the following actions may help:

• Adding more sodium to your diet: If you have persistently low blood pressure, then adding more salt to your diet may help. But it’s important to consult your doctor before increasing salt intake, since too much salt can cause serious medical issues, such as high blood pressure and heart failure.

• Wearing compression socks or stockings: This can help improve circulation by reducing the pooling of blood in your legs.

• Staying hydrated: Drinking enough water prevents dehydration, which reduces blood volume. Low blood volume leads to low blood pressure.

• Exercise: Consult a medical professional about what type of physical activity can help lower blood pressure.

Low Diastolic Blood Pressure Complications

Low diastolic low blood pressure can lead to serious, sometimes life-threatening complications.

Falls

Those with low diastolic pressure can experience symptoms of fatigue or dizziness. When this happens, it can lead to falls, which is especially dangerous for older people who may have brittle bones.

Heart problems 

Low diastolic blood pressure can cause the heart to become stiff, increasing risk for diastolic heart failure. If the heart is stiff and doesn’t relax enough, it won’t be able to fill up with enough blood when it pumps. It can also cause fluid to back up in the lungs. There are currently no medications for diastolic heart failure.

When to See a Medical Provider for Low Diastolic Blood Pressure

To help manage or prevent low blood pressure, you should routinely get your blood pressure checked, especially as you get older. If you have symptoms of low diastolic blood pressure, consult your doctor.