If you have trouble focusing or you’re forgetful sometimes, you may describe it as “brain fog.” Several members of MyLupusTeam have wondered whether brain fog is linked to hydroxychloroquine (HCQ), a lupus medication. While brain fog isn’t a common side effect of HCQ, your brain fog symptoms may actually be caused by the lupus itself.

Here’s what you need to know about HCQ, lupus, and brain fog.

Does Hydroxychloroquine Cause Brain Fog?

HCQ, sold under the brand name Plaquenil, works to block certain proteins in the immune system that are responsible for inflammation. For this reason, it’s often effective at preventing inflammation and long-term organ damage in lupus.

Currently, brain fog isn’t a reported side effect of HCQ, so the timing of your brain fog and beginning HCQ is likely a coincidence. That said, the medication’s labeling does include neuropsychiatric reactions as possible side effects. But these are rare.

These reactions include confusion, mood changes, and sleep problems, which could potentially trigger your brain fog if you experience them. Talk to your healthcare provider about any symptoms you’re experiencing.

In the meantime, there are a few strategies you can try to cope with brain fog, including:

• Avoiding triggers prone to causing flare-ups
• Using memory aids, such as lists, or writing things down
• Getting enough sleep and exercise

“I don’t know what I would do if I didn’t write things down. I’ll put them in my phone as a reminder or in my notes — it really is that bad.”

— A MyLupusTeam member

Lupus Can Cause Brain Fog

Brain fog is common in people living with lupus. In fact, the Lupus Foundation of America indicates 70 percent to 80 percent of people diagnosed with lupus experience brain fog during their lives. If you’re experiencing brain fog, or cognitive impairment, you may notice you are:

• Having trouble recalling memories or remembering facts
• Taking longer than usual to perform tasks or solve problems
• Struggling to hold conversations
• Experiencing difficulty with focus or concentration

Lupus, like rheumatoid arthritis and multiple sclerosis, is an autoimmune disease — a condition in which your immune system attacks your body, causing damage and inflammation. This can result in rashes, sores, or lesions on your skin and it can affect other organs as well.

It can also affect your nervous system and can lead to brain fog. The exact cause of the brain fog can be multifaceted though. For instance, brain fog can be triggered by nervous-system problems, pain, poor sleep, depression, medications, and other health conditions.

Predicting when brain fog will occur isn’t easy, especially because symptoms are often intermittent. In other words, you may go through flare-ups (periods of time when symptoms get worse) and remissions (periods when symptoms are rare).

Also, if brain fog coincides with the start of a new activity, such as starting a sport or taking a new medication, it’s hard to know which one’s responsible. In these cases, talk to your healthcare provider about your concerns and the adverse effects you’re experiencing.

Other Hydroxychloroquine Side Effects May Trigger Brain Fog

HCQ is a fairly slow-acting drug, so it may take weeks to months to see any improvements in your lupus symptoms. You may also feel worse from taking HCQ before you begin to feel better. And though HCQ is considered a safe medication, it can still cause side effects in some people.

Everyone’s body responds differently to HCQ, though. So you may experience side effects or you may tolerate HCQ fairly well. If you do experience side effects, these can include:

• Nausea and vomiting
• Loss of appetite, cramps, and diarrhea
• Tiredness or weakness
• Headache

These side effects can cause you to lose sleep, feel dizzy, or develop headaches, all of which can make your brain fog worse, especially because HCQ’s beneficial effects may not be felt right away.

In rare cases, HCQ may also cause eye damage. Taking a high dose of HCQ or other common antimalarials, such as chloroquine, is a common risk factor for retinal damage. That’s why it is best to do an eye checkup periodically. And combining this medication with other medications could cause adverse reactions as well.

For instance, HCQ has known drug interactions with antibiotics and diabetes medications. (Drug reactions are adverse reactions that occur when mixing two medications.) If your doctor prescribes HCQ, make sure they know everything else you’re taking including supplements.

Other Lupus Treatments Can Cause Brain Fog

Besides HCQ, your rheumatologist might prescribe other lupus medications including steroids, nonsteroidal anti-inflammatories (NSAIDs), and immunosuppressives like methotrexate (Rheumatrex). Some of these medications can trigger brain fog.

For instance, prednisone, a common steroid used to treat lupus, can cause changes in cognition. When taking this medication, it’s possible to be confused or nervous. One MyLupusTeam member noted how prednisone affected their loved one.

They mentioned, “My oldest daughter used to tell me while taking prednisone that she felt like she was trying to think through mud.” Another member said, “I get tired, scattered thoughts and I find myself struggling to focus, and I’m only taking hydroxychloroquine. But, this doesn’t happen as often as it did when I was on prednisone.”

Talk to Your Doctor

Because brain fog often comes and goes in waves, pinpointing the trigger can be challenging. This can also leave you wondering if you imagined what happened. But what you’re experiencing is real and shouldn’t be ignored.

If you’re noticing brain fog, talk with your healthcare provider. It’s possible this symptom is caused by lupus or triggered by other side effects of HCQ. Even a different medication could be the culprit. The key is that you work together to find a solution.