5 Serious Symptoms in Children to Never Ignore

What to keep in mind if your child gets a very high temperature or other worrisome symptoms.

Medically Reviewed by Melinda Ratini, MS, DO on December 27, 2023
7 min read

Runny noses. Stomach aches. An itchy rash. These are a few of the typical ailments that occur in children everywhere.

But what if something more serious develops, like a fever above 103 degrees or a stiff neck? You may not know whether to rush to the emergency room, call the doctor, or simply wait it out at home.

“If your child looks very weak -- sick as they've ever been -- the parents need to call their doctor now,” says pediatrician Barton Schmitt, MD, who supervises the After Hours Call Center at the Children's Hospital in Aurora, Colo., which takes calls for 590 pediatricians every night. “Of those calls, 20% are sent to the ER, 30% need to be seen the next day in the office, and half can be safely cared for at home," Schmitt says.

Some parents may worry that their instinct to head to the ER or urgent care clinic after the pediatrician's office is closed will be questioned by the doctor on call if nothing serious turns up, but it's generally wise to trust your gut feeling.

“Some parents think they shouldn't go to the hospital because they'll be ridiculed, but there's nothing wrong with an ER visit that results in nothing but reassurance,” says Alfred Sacchetti, MD, chief of emergency medicine at Our Lady of Lourdes Medical Center in Camden, N.J., and spokesman for the American College of Emergency Physicians. “If something happened, you wouldn't have been able to live with it.”

Here are common childhood symptoms that may warrant a visit to the doctor's office, 24-hour walk-in clinic, or emergency room. If you have a baby under the age of 1, check WebMD's article on when to take a baby to the doctor or ER, because the criteria are different for babies than for older kids. However, with kids of any age, don't hesitate to ask a health care professional when you're in doubt.


If your child is flushed and hot, your first instinct may be to see a doctor as quickly as possible, but this may not always be necessary.

“We constantly try to teach parents not to look at the thermometer, but what kids' symptoms are and what they look like,” says Schmitt, who created the KidsDoc app for smartphones from the American Academy of Pediatrics (AAP), a triage system that helps parents figure out how to treat kids' symptoms.

A fever is part of the body’s way of defending itself against an infection. If a child has a fever, it means that their immune system is working. A fever, by definition, is 100.4 F, taken rectally. You may want to take a toddler’s temperature under their arm, but be sure to add one degree to the results, to get a more accurate number.

You can give your child medicine such as acetaminophen or ibuprofen (if the child is more than 6 months old) to reduce their fever. But be sure that it's truly necessary, and keep close tabs on the dosage of this or any medication in children, whether it's from a prescription or not. Remember, fever reducers don’t fight the infection that's causing the fever, it just reduces the fever temporarily.

A study published in the journal Pediatrics found that one in four parents give their children fever-reducing medication when their temperature is less than 100 F, but most pediatricians don't recommend treating a fever unless it's above 101 F. And if your child looks well and is eating and drinking, skip the trip to the ER; a high fever by itself doesn't always need immediate medical attention.

“Most fevers in a child are not medical emergencies and can wait until the office opens to see a doctor,” says AAP spokeswoman Ari Brown, MD, a pediatrician based in Austin, Texas. She recommends that you bring your child age 2 or older to the doctor if they have a fever of 104 degrees Fahrenheit or higher, if they look unwell, or if they have had a persistent fever for four or more days in a row . A child younger than 2 should be seen by a doctor within 48 hours of a fever.

How can you tell whether your child's headache is serious enough to warrant immediate medical attention, or if letting them skip school and sleep it off would help?

“Minor headaches go away with over-the-counter pain relievers and/or rest,” Brown says. “Major headaches do not.”

If your child's headache endures for several hours -- or if the pain is so intense that they can't eat, play, or even enjoy their favorite TV show -- call the pediatrician.

“If it's severe enough to incapacitate the child, it needs to be evaluated now,” Schmitt says. “They cannot do any normal activities. All they can do is think about their pain.”

Headaches can be commonly caused by tight muscles in the scalp, rather than a problem related to the brain, but a headache with neurological symptoms (such as confusion, blurred vision, or trouble walking) should be evaluated by an emergency room doctor.

Headaches combined with fever, vomiting, confusion, rash, or stiff neck should also be evaluated quickly as the child could have a serious infection or illness, such as meningitis, which is a medical emergency.

If a child gets headaches often, that needs to be evaluated. Children generally should not get headaches.

Don't be too concerned about a rash on your child's arm or feet; they're generally harmless. If the rash covers their entire body, though, examine it to see whether you should get medical attention.

“If you touch the red rash and it blanches or turns white, then you let go and it turns red again, you usually don't have to worry about it,” Sacchetti says. “Most of the virus rashes and allergic reactions, including hives, will do that.”

A non-blanching rash -- small red or purple spots on the skin that don't change color when you press on them -- can indicate a medical emergency such as meningitis or sepsis, particularly when accompanied by a fever. This type of rash can also appear on the face after violent bouts of coughing or vomiting, so it's not always a sign of something serious, especially if it's just in one area.

To be safe, any time your child has small red or purple non-blanching dots appear on a widespread area, it's best to seek emergency care at once, to rule out a more serious condition.

Another widespread rash which can be a medical emergency are hives which appear with lip swelling. Hives should be immediately treated with diphenyhadramine (Benadryl). Call 911 immediately if your child has any swelling of the face, lips, or mouth or has any trouble breathing. These symptoms suggest an anaphylactic reaction, which is a serious, life-threatening allergic reaction.

When your child has food poisoning or gastroenteritis (the so-called “stomach flu," though it has nothing to do with influenza), monitor how often they're throwing up or having diarrhea.

Vomiting and diarrhea can lead to dehydration. If it is mild dehydration, your doctor may recommend giving oral electrolyte solutions at home, though treatment depends in part on the child's age. If your child seems to be getting worse (not urinating or acting sick), you should see your doctor.

Vomiting three times in an afternoon may not lead to dehydration, but eight bouts of diarrhea in eight hours probably will, as will a combination of vomiting with diarrhea. Dehydration needs to be closely monitored and sometimes needs emergency treatment.

“If they're losing it below and not able to retain the ideal fluid from above, they may need some IV fluids or prescription medication to stop the vomiting,” Schmitt says. “The younger kids are at the greatest risk of dehydration.”

A stiff neck can indicate meningitis, a true medical emergency, so parents may panic if they see their child standing rigidly, not moving their necks, or refusing to look left or right. But a stiff neck by itself is rarely anything more than sore muscles.

“Look at a constellation of symptoms, not just one in isolation,” Brown says. “A stiff neck alone might mean you slept funny. Meningitis is a combination of fever with a stiff neck, light sensitivity and headache.” Meningitis can also be accompanied by vomiting and lethargy.

A stiff neck with a fever might be as simple as a tonsil inflammation or swollen lymph node, not meningitis; calling the pediatrician could ease your fears. Of course, if trauma caused a hurt neck, that's a clear reason to head to the ER.