10 Symptoms ER Doctors Say to Never Ignore

Emergency room doctors see the worst-case scenarios, the weird fluke accidents, the mysterious ailments and miraculous recoveries. They’re also no strangers to the symptoms that patients didn’t take seriously until it was almost too late.

Here, ER docs share 10 red flags that patients often ignore—but which should be addressed urgently.

Sudden confusion or personality change

One minute, your mom is lucid and chatty—the same as every other day. The next, she can’t remember where she is or who you are, her words are garbled, and she can’t summon the name of the vegetable she just started slicing. “You might think, well, maybe she’s just tired,” says Dr. Yanina Purim-Shem-Tov, executive vice chair of emergency medicine with the Rush University System for Health at Rush University Medical Center. “But this is absolutely an emergency, and we should see these people right away.” 

Sudden confusion or a personality change could indicate a stroke, an infection like sepsis, or low blood sugar, she adds, which is why it’s essential to seek immediate care at the ER.

Unusual upper back pain

Always pay attention to severe pain in your upper back or between your shoulder blades, especially if it comes on suddenly or is accompanied by other symptoms like nausea or dizziness. “Don’t shrug it off,” Purim-Shem-Tov says. “Call 911. It could be a sign of a heart attack.”

Read More: When to Go to the Emergency Room vs. Urgent Care

For some people—including women—heart attack pain shows up in surprising places, like the back, neck, or jaw. Purim-Shem-Tov’s patients often describe it as a “tearing pain” that sometimes radiates down one or both arms. This kind of pain could also be a sign of aortic dissection, or tearing in the aorta, which is the main artery carrying blood from the heart. While people sometimes try to endure it at home, convinced they simply pulled a muscle, “this is not that,” she says, “especially in patients who are at risk—for example, those who have hypertension and suddenly have this severe upper back pain.”

Sudden, unexplained severe itching

If you can’t stop scratching—especially if you itch all over instead of in just one spot—you could be experiencing the beginning of an anaphylactic reaction. “When somebody feels really itchy and uncomfortable, and all of a sudden they start to get flushed, that’s really concerning,” says Dr. David Benaron, vice chair of the department of emergency medicine at the University of Nevada, Reno School of Medicine. “I would want them to come see us ASAP.”

Read More: How to Tell if You’re Allergic to Alcohol

Even more alarming: if your symptoms are accompanied by nausea, vomiting, or diarrhea. People often don’t realize it, but digestive distress is a pillar of anaphylaxis, Benaron says. “You eat something and all of a sudden you’re like, ‘Oh God, I’m terribly nauseated,’” he says. “You can get hives inside your gastrointestinal tract, and it becomes really irritated and you get these GI symptoms.”

Vomit that’s a certain color

The color of your vomit can tell ER doctors a lot about how sick you are. Benaron is especially inclined to worry when children throw up bile, which is usually green, because “that can indicate a really dangerous obstruction in their intestines,” he says. Meanwhile, if your throw-up looks like coffee grounds—it’s dark brown or even black—it might include blood that’s been partially digested by stomach acids. 

Vomit that resembles coffee grounds “would mean to me that there’s some bleeding,” Benaron says. Red vomit, however, triggers even louder alarm bells, because such a bright color indicates “there’s quite a lot of blood moving.”

A sense of doom 

When extreme anxiety strikes out of nowhere, take it seriously—especially if it’s accompanied by trouble breathing, a racing heart, or dizziness. It could be the body’s reaction to a heart attack or blood clot, or a severe allergic reaction. “If it’s new, intense, or feels different than usual anxiety, don’t ignore it,” Purim-Shem-Tov says.

Read More: The Difference Between Stress and Anxiety

On Christmas a few years ago, for example, Purim-Shem-Tov treated a 31-year-old patient who showed up at the ER pacing back and forth, overcome with anxiety and a sense of dread. “He wasn’t really complaining of chest pain or shortness of breath,” she recalls. “All he was feeling was this doom sensation—he thought it was anxiety.” The man ended up experiencing a massive, fatal heart attack, which drives home why it’s important to take extreme anxiety seriously, Purim-Shem-Tov says, especially if it’s out of character for you.

Randomly passing out

Fainting or almost fainting without a clear cause can be a red flag for abnormal heart rhythms, internal bleeding, or neurological issues. That said, it could also be the result of dehydration or standing up too fast. “Dizziness or lightheadedness is probably the bane of every emergency physician’s existence,” Purim-Shem-Tov says, since it’s such a vague, imprecise symptom that can point to a wide spectrum of possible causes.

Read More: 12 Weird Symptoms Endocrinologists Say You Should Never Ignore

That’s why she advises always getting fainting checked out, especially if it happens while you’re sitting or lying down, working out, or experiencing other unusual symptoms. As frustrating as it can be to encounter something as ambiguous as dizziness, “we also know that we need to be looking for something serious,” she says.

White poop

If you’re having white bowel movements, it’s possible your bile tract could be obstructed, meaning bile—which contributes to the normal color of stool—isn’t reaching the intestines. “The scary thing that does that is pancreatic cancer,” Benaron says. “The pancreas wraps around the bile system and the bile builds up, causing yellow in the eyes and white-colored stools.” It’s worth bringing up with your doctor or at the ER as soon as you notice the change.

Urinary retention

People sometimes go to the ER for constipation sooner than they need to—after three or four days of not being able to go to the bathroom, before they’ve tried reliable remedies like stool softeners, Benaron says. But there is one clear sign that constipation needs to be addressed urgently: you’ve stopped being able to pee. A full, impacted bowel “can cause bladder obstruction because, anatomically, it can press a lot in that pelvic region,” he says. “If somebody’s not urinating, that’s a big problem.”

Read More: 12 Weird Symptoms Dermatologists Say You Should Never Ignore

Sometimes, when ER doctors treat constipation by manually removing stool from the rectum, the patient resumes being able to pee again on their own. Other times, however, “you need to put a catheter in their urethra to drain the bladder,” he says. Not resolving the matter in a timely manner can ultimately lead to kidney failure, Benaron adds, so don’t delay seeking care.

Shortness of breath while lying down

Becoming short of breath while you’re lying down or resting isn’t the same as feeling winded while you’re climbing 10 flights of stairs. Gasping for air when you’re horizontal could signal heart failure, a blood clot in the lungs, or a silent heart attack, Purim-Shem-Tov says. “Your lungs could be filling up with fluid, and when you lay back, it’s almost like you’re drowning in your own fluids,” she says. “Shortness of breath at rest is just as important—or maybe even more important—than shortness of breath when you’re exerting yourself.”