Lupus is not something you catch or do to yourself

You cannot get lupus from another person, and nothing you did caused it. Lupus develops when your immune system starts attacking your own cells and tissues by mistake. Doctors do not yet fully understand why this happens in some people and not others, but they have identified several factors that make it more likely: your genes, your sex, your race or ethnicity, and sometimes exposure to certain triggers like sunlight or infections.

If you have been diagnosed with lupus, or if you are trying to understand why a family member has it, the most important thing to know is that this is a medical condition, not a personal failure. The disease runs in families sometimes, but having a relative with lupus does not mean you will definitely develop it.

Key Takeaways

  • Lupus develops when your immune system mistakenly attacks your body's own cells, and this happens because of a combination of genes you inherited and environmental triggers you encountered.
  • Women are nine times more likely to develop lupus than men, and the disease is more common in Black, Hispanic, Asian, and Native American populations.
  • Sunlight exposure, infections, certain medications, and hormonal changes can trigger lupus in people who are genetically predisposed to it.
  • Having a parent or sibling with lupus increases your risk, but most people with a family history of lupus never develop the disease themselves.
  • Lupus is not contagious, not caused by anything you did, and not preventable even if you know you are at risk.

The genetic foundation: why some families carry lupus

Lupus tends to run in families because of inherited genes that affect how your immune system works. If your mother, father, sister, or brother has lupus, your risk of developing it is higher than someone with no family history. However, the risk is still relatively low—most people with a close relative who has lupus will never develop it themselves.

Scientists have identified multiple genes involved in lupus, not just one. This means that even if you inherit genes that increase your risk, you may not develop the disease unless other conditions are also present. Your genes load the gun, but something else has to pull the trigger.

Environmental triggers that can activate lupus

Even if you carry genes that make lupus possible, the disease often does not develop until something in your environment sets it off. Sunlight exposure is one of the most common triggers. Ultraviolet (UV) radiation can damage skin cells and cause them to release substances that activate the immune system in people who are genetically vulnerable.

Infections are another major trigger. Viral infections like Epstein-Barr virus (the virus that causes mononucleosis) have been linked to lupus development in some people. Bacterial infections can also play a role. Your immune system fights the infection, but in genetically susceptible people, this response sometimes does not turn off properly and begins attacking the body's own tissues instead.

Certain medications can trigger a lupus-like condition, though this is usually different from the lifelong form of lupus. Medications that have been associated with drug-induced lupus include some blood pressure drugs, antibiotics, and anti-seizure medications. If you develop symptoms after starting a new medication, tell your doctor—stopping the medication usually resolves the symptoms.

Hormonal changes also appear to play a role. Lupus often develops or worsens during puberty, pregnancy, or menopause, when hormone levels shift. This may explain why women are diagnosed with lupus far more often than men.

Why women and certain racial groups are at higher risk

Lupus is diagnosed in women about nine times more often than in men. This difference likely stems from both genetic and hormonal factors. The female hormone estrogen may amplify immune responses in ways that make lupus more likely to develop. Additionally, women's immune systems naturally respond more strongly to infections and vaccines than men's do, which is protective in some situations but may increase lupus risk in genetically vulnerable women.

Lupus is also more common in Black, Hispanic, Asian, and Native American populations than in white populations. People in these groups tend to develop lupus at younger ages and often experience more severe symptoms. The reasons for these differences are not fully understood but likely involve both genetic variation and differences in access to healthcare that affect when the disease is diagnosed.

What happens when lupus develops

Lupus usually develops slowly. You may have the genetic predisposition for years or decades before any symptoms appear. When a trigger occurs—sunlight exposure, an infection, a medication, or sometimes no identifiable trigger at all—your immune system begins producing antibodies that attack your own cells. These antibodies circulate in your blood and can damage joints, skin, kidneys, heart, lungs, and other organs.

The first signs of lupus are often mild and easy to miss: fatigue, joint pain, a rash across the cheeks and nose, or mouth sores. Some people have a single flare and then go into remission. Others experience cycles of flares and periods of lower activity. The unpredictability is part of what makes lupus difficult to live with.

Stress and other factors that may worsen lupus

Once lupus develops, certain factors can make it worse. Stress is a common flare trigger, though the exact mechanism is not clear. Infections can also trigger flares in people who already have lupus. Lack of sleep and smoking have both been associated with worse lupus activity.

Some people find that their lupus is triggered or worsened by specific things in their environment or lifestyle. Keeping track of what happens before a flare—what you were doing, what you were exposed to, what was happening in your life—can help you and your doctor identify your personal triggers and develop strategies to avoid them when possible.

Can lupus be prevented if you know you are at risk?

If you have a family history of lupus or other risk factors, there is no proven way to prevent the disease from developing. You cannot prevent lupus by avoiding sun, managing stress, or taking any particular medication before symptoms appear. Some doctors recommend that people at high risk take steps to protect their skin from sun exposure and manage stress, but these are general health measures, not lupus prevention.

What you can do is be aware of early symptoms and seek medical attention if you notice signs like unexplained fatigue, joint pain, or a characteristic rash. Early diagnosis and treatment can prevent serious organ damage and help you manage the disease more effectively.

Frequently Asked Questions

Can I catch lupus from someone who has it?

No. Lupus is not contagious. You cannot catch it from a family member, friend, or anyone else, no matter how close your contact. It develops because of your own genes and environmental triggers, not because of exposure to another person with the disease.

If my mother has lupus, will I definitely get it?

No. Having a parent with lupus increases your risk, but most people with a family history of lupus never develop it. Your risk depends on which genes you inherited and what environmental triggers you encounter over your lifetime. You may carry the genetic predisposition without ever experiencing symptoms.

Can I get lupus from taking certain medications?

Some medications can cause a lupus-like condition called drug-induced lupus, which usually goes away when you stop taking the medication. This is different from systemic lupus erythematosus (SLE), the lifelong form. Tell your doctor if you develop symptoms after starting a new medication.

Does sunscreen prevent lupus?

Sunscreen does not prevent lupus from developing. However, if you already have lupus, protecting your skin from sunlight can help prevent flares. For people at high risk, sun protection is a reasonable precaution, but it is not a may provide against developing the disease.

Why do men get lupus less often than women?

The reasons are not completely understood, but hormones play a major role. Estrogen appears to amplify immune responses, and women's immune systems naturally respond more strongly than men's. Genetic differences between men and women may also contribute to the difference in lupus rates.