If you have lupus and blood pressure concerns, you may be wondering, “Can lupus affect blood pressure?” Up to 74 percent of people with systemic lupus erythematosus (SLE) — the most common form of lupus — experience hypertension (high blood pressure)​. However, hypotension (low blood pressure) can also occur. Hypotension happens when blood flows through your blood vessels with less force than usual, which can reduce the amount of oxygen delivered to your organs.

Low blood pressure can have multiple causes, including dehydration, medication side effects, and nervous system changes — some of which may be linked to lupus. You might not realize you have low blood pressure unless your healthcare provider checks it. However, certain symptoms, like dizziness or fainting, may signal that it’s time to talk to your doctor or rheumatologist (a specialist in autoimmune conditions).

Read on to learn five key facts about lupus and low blood pressure.

1. Normal to Low Blood Pressure Could Cut Cardiovascular Disease Risk

In 2018, the American Heart Association and American College of Cardiology changed the definition of high blood pressure from 140/90 millimeters of mercury (mm Hg) or higher to 130/80 mm Hg or higher for the general population.

A study of people with SLE found that those with high blood pressure were at a greater risk for heart-related emergencies compared to those with a blood pressure below 130 mm Hg​. Individuals with higher blood pressure were more likely to experience:

• Heart attack
• Angina (chest pain due to reduced blood flow to the heart)
• Heart failure
• Peripheral vascular disease (a condition that reduces blood flow to the limbs)
• Blood clots and stroke

Specifically, researchers found that more than 10 percent of people with lupus who had an average blood pressure of 130-139/80-89 mm Hg experienced a major cardiovascular event, compared to fewer than 5 percent of those with a lower average blood pressure​. These findings suggest that blood pressure below 130 mm Hg is an appropriate target for people with lupus.

2. Low Blood Pressure Isn’t Always a Problem

If you have low blood pressure, you may wonder if it can be too low. According to the American Heart Association, there is no single blood pressure number that is considered dangerously low — unless it causes symptoms​. In other words, if your blood pressure reading is low but you feel fine, there’s no immediate cause for concern.

However, low blood pressure can become problematic if it leads to symptoms such as:

• Nausea
• Fainting, dizziness, or light-headedness
• Excessive thirst or signs of dehydration
• Blurry vision
• Confusion or difficulty thinking clearly
• Unusual fatigue or weakness

One MyLupusTeam member described their symptoms of low blood pressure, which prompted them to visit the emergency room (ER): “Speaking from experience, I was light-headed and dizzy with low blood pressure. I went to the ER and came back with a diagnosis of hyponatremia (low sodium levels).”

If you experience any of these symptoms, it’s important to check in with your doctor. Try to note when your symptoms occur, as certain activities — such as standing up too quickly or going long periods without food — can sometimes contribute to low blood pressure episodes. Tracking patterns can help your doctor determine whether treatment is needed.

3. Related Conditions Can Lead to Low Blood Pressure

People with SLE may also have comorbidities (coexisting conditions) that can contribute to low blood pressure. Some of these conditions may be related to how lupus affects different organ systems, such as the endocrine system. The endocrine system helps regulate essential functions in the body, including metabolism, growth, blood pressure, and stress response.

Some people with lupus also have endocrine disorders, such as thyroid disease or diabetes. One study found that about 5 percent of people with lupus also had hypothyroidism (underactive thyroid)​. Another study found that people with SLE had a 22 percent higher risk of developing type 2 diabetes compared to those without lupus. Some endocrine problems, such as hypothyroidism, Addison’s disease, and occasionally diabetes, can cause low blood pressure.

Although some comorbidities may explain low blood pressure, there are also many other possible causes — such as nutritional deficiencies or dehydration — that may not be related to lupus. If you’re concerned about low blood pressure, talk to your doctor so they can help determine the cause and decide if treatment is needed. Keeping track of symptoms and when they occur can provide helpful clues for your healthcare provider.

4. Some Medications Can Cause Low Blood Pressure

Low blood pressure can be a side effect of several medications, some of which may be part of your lupus treatment plan. These drugs include diuretics (water pills) and treatments for hypertension. High blood pressure is common among people with lupus, especially those with lupus nephritis (a type of lupus that affects the kidneys).

Some people with lupus may take diuretics to manage fluid retention from corticosteroids like prednisone. If you have lupus and blood pressure medication is prescribed to you, your blood pressure may be low. Also, meds for other symptoms of lupus, like rituximab (Rituxan), could make your blood pressure lower than normal.

In addition, taking some prescription or over-the-counter drugs along with hypertension treatments can cause low blood pressure. Talk with your doctor to see if any of the medications you’re using to manage heart issues with lupus may be at the root of your low blood pressure.

Some antidepressants, particularly those that affect the nervous system’s regulation of blood pressure, can also cause low blood pressure. If you’re taking medications for depression, check with your doctor to see if they could be contributing to low blood pressure symptoms.

5. Lifestyle or Drug Changes May Help Manage Low Blood Pressure

Low blood pressure may not require treatment if it doesn’t cause symptoms like light-headedness, nausea, or dizziness, or if it doesn’t interfere with daily activities. However, if low blood pressure leads to symptoms, your doctor may recommend lifestyle adjustments or medical interventions that are safe for you.

Some MyLupusTeam members report that eating more salt or electrolytes, per their doctor’s recommendations, helps their low blood pressure. One member wrote, “I drink Propel-flavored water. It’s really good — has electrolytes to up your salt! Chicken soup has high sodium.”

Another member, discussing their partner’s experience, said, “We’ve also heard she needs to keep her salt levels up and fluid intake high as well.”

While sodium and electrolyte balance may help some people with low blood pressure, it’s essential to consult your doctor before making major dietary changes, such as increasing salt intake. Managing sodium levels is especially important for people with lupus, particularly those with kidney involvement.

If you’re experiencing symptoms of low blood pressure, talk to your doctor about the best strategies for you. They can help determine whether dietary changes, medication adjustments, or other approaches may be beneficial.

Talk With Others Who Understand

MyLupusTeam is the social network for people with lupus and their loved ones. On MyLupusTeam, more than 235,000 members come together to ask questions, give advice, and share their stories with others who understand life with lupus.

Have you ever wondered whether lupus can cause high blood pressure or low blood pressure? If you have low blood pressure, how does it affect you? Share your experience in the comments below, start a conversation by posting on your Activities page, or connect with like-minded members in Groups.