Avril Lavigne opened up again recently about her struggle with Lyme disease, a tick-borne illness she says left her bedridden for months and desperate for answers. The 30-year-old singer told Good Morning America last week that she saw many doctors and underwent a battery of tests in the last year, but that it wasn’t until she found a Lyme disease specialist that she was given a correct diagnosis.

“I was in Los Angeles, literally, like the worst time in my life and I was seeing, like, every specialist and literally, the top doctors. It’s so stupid,” Lavigne said in an interview televised June 29. She said that some misdiagnosed her symptoms—debilitating pain and fatigue—as chronic fatigue syndrome or depression, while others told her she was simply dehydrated or exhausted from touring.

“This is what they do to a lot of people who have Lyme disease,” she said. “They don’t have an answer for them so they tell them, like, ‘You’re crazy.'”

Lavigne began to suspect she had Lyme disease—the number-one insect-borne disease in the United States—a few months after she began feeling exhausted and lightheaded. Her symptoms eventually got so bad she felt like she couldn’t breathe, talk, or move. “I thought I was dying,” she told People in April.

RELATED: 15 Diseases Doctors Often Get Wrong

So why did it take so long for Lavigne to get answers? And could her experience happen to others, as well?

Fortunately, most cases of Lyme disease are caught and treated much earlier, says Dr. Anne R. Bass, a rheumatologist at the Hospital for Special Surgery in New York City, and this degree of misdiagnosis isn’t very common. But pinpointing this type of infection is not an exact science, and symptoms are not always crystal clear.

“Many people will develop a bulls-eye rash, which makes it fairly easy to diagnose,” she said. But this telltale symptoms is sometimes faint or on hidden parts of the body, and some people don’t get one at all.

“Other early symptoms, like fever or aches and pains, could be attributed to a virus or flu,” Bass said. “So if you don’t see a rash, you might not even go to the doctor—or it’s possible your doctor might not recognize it.” (Some Lyme disease cases go away on their own, she adds, so it’s possible to have had it and never known.)

RELATED: 13 Conditions That Mimic Fibromyalgia

Most physicians, especially those who practice in tick hot-spots like the northeastern United States, know to look out for Lyme disease symptoms during spring and summer months. But the disease is less prevalent in Southern California, where Lavigne said she was seeking treatment. If a patient hasn’t had a rash and doesn’t remember being bitten, doctors there may be slower to identify ticks as a potential factor.

Bass says that anyone who’s experienced fatigue or joint pain for several months should think back to when their symptoms started, and whether they spent time in area of the country known for Lyme disease outbreaks. A blood test cannot confirm whether you are currently infected, but it can tell if you have been exposed to Lyme bacterium in the past. (It actually tests for antibodies, which develop a few weeks after a person has been infected and remain in the blood forever.) Doctors can use these test results, along with a person’s current symptoms, to make a diagnosis.

“But even these test results can be complex and confusing, especially for physicians who aren’t used to dealing with Lyme,” Bass said.

Some doctors also believe that Lyme disease can be diagnosed without a positive blood test, she adds—although there’s no evidence that these methods are accurate or that antibiotics, in these cases, work any better than placebo.

RELATED: 27 Mistakes Healthy People Make

(Lavigne did not reveal exactly how she was diagnosed or whether she tested positive for Lyme antibodies, although she did say she had blood tests when she first became ill.)

Once Lyme disease is diagnosed, two to three weeks of oral antibiotics usually help patients feel better and eliminate all symptoms. If it goes untreated for several months, however, a longer course of drugs—usually four weeks—is often needed. In extreme cases, antibiotics may also be given through an IV.

Bass said that it’s uncommon for patients to be prescribed antibiotics for more than a month, even if they continue to experience fatigue and pain.

“It does take longer for them to get better when there is a delay in diagnosis, but it doesn’t really change our duration or course of treatment,” she said. “They may just need to rest and take it easy a bit longer until they have their energy back.”

RELATED:  13 Ways Inflammation Can Affect Your Health

Lavigne is finally feeling better, and says she expects to make a full recovery. That’s a good thing, since 10 to 20 percent of people with Lyme disease continue to experience symptoms for months or even years after treatment. This condition is sometimes called chronic Lyme disease, although it’s technically known as post-treatment Lyme disease syndrome.

Doctors aren’t sure what causes post-Lyme syndrome (some believe that symptoms are due to other tick-borne illnesses, or to chronic conditions like rheumatoid arthritis), and treatments like long-term antibiotic therapy are controversial. But a recent study from Johns Hopkins University showed that one thing is clear: Prolonged Lyme-related illness is more common than was once believed.

“Our data show that many people who have been diagnosed with Lyme disease are in fact going back to the doctor complaining of persistent symptoms, getting multiple tests, and being retreated,” the study authors said in a news release. “It is clear that we need effective, cost-effective, and compassionate management of these patients to improve their outcomes, even if we don’t know what to call the disease.”

RELATED: What You Should Do If You Find a Tick

This article originally appeared on Health.com.