Oh no, not again.

You wake up generally feeling well, but you start to sense that something isn’t quite right — you feel a bit more stiffness after exercising than you normally do, though it quickly disappears. And you’re more fatigued and lethargic than usual, yet you’re beginning to have problems sleeping.

Although these are fairly subtle signs, you’ve been through this enough times before to realize what’s going on. You’re beginning to experience a flare of your usually well-controlled rheumatoid arthritis.

As the flare develops, you get twinges of stabbing pain that eventually morph into a constant, burning pain. Your joints swell, and you develop a low-grade fever. You eventually lose so much mobility in your joints and experience such extreme fatigue that you find it next to impossible to function. According to the Arthritis Foundation, RA is a disease of “ups and downs.” You may feel fine one day and find it almost impossible to get out of bed and function the next. These episodic symptom exacerbations are called flares.

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Over the last 20 years, advances in the medications used to treat RA, combined with early, aggressive treatment, have made it much easier to control much of the systemic inflammation and resulting damage to the body’s joints and organ systems that characterize this incurable, autoimmune disorder.

Even so, flares still occur.

“It is not always clear what causes a flare,” says Dr. Vivian P. Bykerk, director of the Inflammatory Arthritis Center in the Division of Rheumatology at the Hospital for Special Surgery in New York.

“Sometimes a patient’s disease hovers between good control and slight worsening,” which can lead to flares, she explains. “People who are not in deep remission are more likely to flare. Also, reduction in medication use, either because of [patient] problems with compliance or because of intentional reduction, can be associated with flares,” Bykerk says. “Other factors can also be involved, such as a recent viral infection, difficult life events, poor diet, etc.”

According to RheumatoidArthritis.net, flares are surprisingly common. A 2013 survey of 1, 000 people with RA conducted by the website found that more than 96 percent said they experience a flare at least once per year. Bykerk agrees. “Flares are frequent events,” she says. It is not uncommon for most patients to experience a flare between physician visits.”

The RheumatoidArthritis.net survey found that almost 23 percent of the participants indicated that they have a flare each month, close to 28 percent have a weekly flare and just under 27 percent experience daily flares. The survey also showed that flare length varies widely. Forty percent of those surveyed indicated that their flares last less than a week, and 13 percent said they last a year or more.

Despite the fact that the majority of people with RA experience flares, there is no standard definition of this phenomenon. Symptoms of a flare can vary widely from person to person, and rheumatologists and patients define them differently. “For research purposes, flares are usually based on clinical measures of disease activity using the [Clinical Disease Activity Index] and [Disease Activity Score 28],” Bykerk says. They can be found at CDAI and DAS28.

Patients, in contrast, usually rate their flares based on “the presence and amount of pain, stiffness and fatigue, as well as on their ability to function and participate in the activities of daily life,” she adds.

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Flares with known triggers are usually temporary and can sometimes be treated using self-care measures like rest, hot or cold packs and nonsteroidal anti-inflammatory medications like ibuprofen. Flares that occur unpredictably, with no discernible trigger, often respond poorly to self-care and may require a visit to the doctor and a medication adjustment before they resolve. “If a flare has not persisted for too long it is usually easy to get back under control,” Bykerk says. “If an interruption in medication due to surgery, for instance, causes a flare, most of the time disease activity can be controlled again by reinitiating the medication, though this is not always true,” she adds.

It’s important to try to bring flares under control because joint and tissue damage can occur during flares. “Studies have shown that frequent flares are associated with damage progression,” Bykerk says. “Medication may need to be increased to stop them from occurring, and steroids are often needed.”

Flares don’t just affect adults with RA. They can also be a problem in children with juvenile idiopathic arthritis, an umbrella term for seven different forms of arthritis that can affect children and teens 16 years of age and younger. “A large Canadian study that found that about 40 percent of [children with JIA] flare within a year after their disease becomes inactive,” says Dr. Jay Mehta, the clinical director of the Division of Rheumatology at Children’s Hospital of Philadelphia.

“The same study found that, in patients who were able to stop treatment, about 30 percent of children flared within a year of stopping treatment,” Mehta says. “Other studies have found that about 50 percent of kids eventually flare after stopping treatment. Some of them flare within a few weeks and some of them flare after a few years of disease inactivity.”

According to Mehta, flares in children can be treated differently based on how severe they are. “If they involve a couple of joints, we can manage them by injecting the joints with corticosteroids,” he says. “If they involve more joints or have more systemic symptoms, they may require a medication change.”

“We try to avoid using oral or IV steroids to treat JIA, if possible, but sometimes systemic steroids are the only thing that can get the disease under control quickly,” he adds. “Treating quickly is important to avoid joint damage, leg length discrepancies and muscle atrophy. In the case of systemic JIA, severe flares can lead to macrophage activation syndrome, which is life-threatening.”

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Is it possible to reduce the chances of experiencing a flare? According to Everyday Health, it’s important to avoid any known triggers and keep stress at a minimum, if possible. However, these measures alone cannot prevent flares, so develop a flare management plan with your doctor and put it in place at the earliest signs.

Once a flare starts, balance the need for rest and activity. Rest is important, but too much rest can actually worsen RA flares. And finally, call on family and friends for support.

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Disease Flares Are Common in People With Rheumatoid Arthritis originally appeared on usnews.com