Heartburn is such a common problem you'd think it would be simple to spot and treat.

But sometimes acid reflux symptoms are less than obvious or easy to mistake for something else.

If left untreated, heartburn can lead to Barrett's esophagus, which is a precursor to cancer, said Dr. Timothy Pfanner, assistant professor of internal medicine at Texas A&M Health Science Center College of Medicine, in College Station.

Here are some symptoms—both common and unusual—that could mean you have acid reflux.

Chest pain

Chest pain, which occurs because stomach acid is splashing into the esophagus, is the classic symptom of heartburn. But the pain can last longer and be more intense than expected. Many people mistake heartburn for a heart attack. You can never ignore chest pain, especially if it gets worse when you exercise or exert yourself.

If you're having chest pain, check with your doctor to make sure you're not having a heart attack, said Dr. Walter Coyle, gastroenterologist with Scripps Clinic Torrey Pines in La Jolla, Calif.

Pain worsens at rest

The acid that is supposed to stay in your stomach is more likely to escape into your esophagus when you lie down or bend over, causing heartburn.

"If you're sitting up straight, gravity helps keep food in the stomach," said Coyle. "If you lose the gravity, you're more prone to reflux."

That's why people with chronic heartburn raise the head of their bed, and why they shouldn't eat big meals right before bedtime.

Post-meal pain

Pain that sets in right after a meal—especially a big meal—often means the stomach is overloaded and its contents have nowhere to go but up. But you may be able to prevent this without taking medication.

"I would stress not eating big, fatty meals and watching [your intake of alcohol and tobacco]," said Coyle.

And it's another reason not to recline after dining.

Bitter taste

Sometimes acid escaping from your stomach can make its way into the back of your throat, leaving an icky, bitter taste in your mouth. In really extreme cases, this can cause choking.

If that happens—especially at night—you should see a doctor. "I'm very aggressive with therapy if patients wake up choking," said Coyle, adding that he usually recommends acid-suppressing medications like proton pump inhibitors, H2 blockers, and antacids.

Hoarseness

You might think you're in the early stages of a cold when your voice starts cracking, but hoarseness can be another heartburn symptom.

If stomach acid is seeping into your esophagus it can irritate your vocal cords, said Pfanner, who is also a gastroenterologist at Scott & White, in Temple, Texas. Pay attention to when your voice sounds more husky than usual. If it's after you've eaten, you may have reflux.

Sore throat

A sore throat is another classic cold or flu symptom that might actually be caused by digestive problems.

If your throat tends to ache only after meals, you may have heartburn. Unlike with a cold or the flu, however, this type of sore throat can also be chronic. If you don't develop other symptoms, such as sniffling or sneezing, consider acid reflux.

_________________________________________________________________________

More from Health.com:

5 Steps to Take If Heartburn Won’t Quit 

Heartburn? 7 Medications That Can Help 

9 Medications That Can Cause Heartburn 

_________________________________________________________________________

 

Cough

Many respiratory symptoms, such as chronic cough and wheezing, can also be due to heartburn, likely because stomach acid is getting into your lungs.

If you suspect heartburn is at the root of your breathing difficulties—possibly because it occurs immediately after eating—you may want to talk to your doctor about getting a pH test. The test is an outpatient procedure that measures the amount of acid in your esophagus over a 24-hour period and can help determine if you have acid reflux.

Asthma

The coughing and wheezing from heartburn can get so bad they could become triggers for asthma.

It is not clear, however, if frequent heartburn actually causes people to develop asthma. Although many people who have heartburn also have asthma and vice versa, the reasons for this overlap aren't clear.

Experts think stomach acid can trigger nerves in the chest to constrict your breathing tubes in order to keep acid from entering. Again, a simple pH test to look for acid in your esophagus may help you get to the bottom of the problem.

Nausea

Nausea is associated with so many things that it can be hard to attribute it to reflux. But, Coyle said, "in some people, the only manifestation they have of reflux is nausea. If you have nausea and can't figure out why, one of the things [to] think about is reflux."

And if the nausea tends to come on right after meals, that's even more of an indication that it might be acid reflux. If so, a regular antacid treatment such as an over-the-counter acid-countering medicine could cut down on your discomfort.

Extra saliva

If your mouth all of a sudden starts producing extra saliva, it could be water brash, which is highly suggestive of acid reflux, Coyle said.

It involves the same nerves and reflex as when you vomit. "It is your body trying to wash out an irritant in your esophagus," he said.

Trouble swallowing

Over time, the continuous cycle of damage and healing after acid reflux causes scarring, Pfanner said. This, in turn, causes swelling in the lower-esophagus tissue, resulting in a narrowing of the esophagus and difficulty swallowing.