After a head impact, a concussion in a child shows up as a combination of physical, cognitive, and behavioral changes, and not all of them appear right away. Some signs are obvious, like a headache or vomiting, but many are subtle: answering questions a beat too slowly, seeming “off,” or becoming unusually irritable. Knowing what to watch for in the first minutes, hours, and days after a hit can help you catch a concussion that might otherwise go unnoticed.
Physical Signs to Watch For
The most common physical symptom of a concussion is a headache, and most children will mention it if they’re old enough to describe what they feel. Beyond that, look for nausea or vomiting, sensitivity to light or noise, blurry vision, dizziness, and balance problems. A child who seems unsteady on their feet, squints in normal lighting, or complains that sounds are “too loud” is showing classic concussion signals.
Fatigue and sleep changes also count. Some children become unusually drowsy soon after the injury. Others have trouble falling asleep that night or sleep far more than usual over the following days. Any noticeable shift in your child’s sleep pattern after a head impact is worth taking seriously.
Cognitive and Emotional Changes
Concussions affect how the brain processes information, so the signs often look more like a thinking problem than a physical injury. The CDC lists these cognitive symptoms: trouble thinking clearly, feeling slowed down, difficulty concentrating, feeling foggy or groggy, and problems with short- or long-term memory. In school-aged children (ages 5 to 17), you might notice them answering questions more slowly than usual, struggling to focus on activities that would normally hold their attention, or having suddenly slower reaction times.
Emotional shifts can be just as telling. A concussed child may become irritable, anxious, unusually sad, or more emotional than normal. Mood, behavior, or personality changes that seem out of proportion to the situation are a red flag, especially when they follow a blow to the head or body. These emotional symptoms are easy to dismiss as tiredness or a bad mood, but in the context of a recent impact, they matter.
Signs in Infants and Toddlers
Children who can’t yet describe their symptoms show concussions differently. According to the American Academy of Pediatrics, younger children often become upset, cranky, or extra fussy after a concussion. They may grow more clingy than usual, and their sleeping and eating patterns can change. An infant who suddenly refuses to nurse or eat, or who cries inconsolably after a head bump, is showing warning signs that need medical attention.
Because toddlers and infants can’t tell you they have a headache or feel foggy, you’re looking for behavior that’s “not like them.” Trust your instinct here. A parent who knows their child’s baseline is often the best detector of something being wrong.
Symptoms Can Be Delayed
One of the trickiest things about concussions in children is that symptoms don’t always show up immediately. A child can seem perfectly fine right after a fall or collision, then develop headaches, confusion, or mood changes hours later. Some symptoms take a full day or two to emerge. This means you need to keep watching your child closely for at least 24 to 48 hours after a significant head impact, even if they initially seem okay.
Check in periodically. Ask how their head feels. Notice whether they’re moving and talking normally. Pay attention at bedtime and the next morning, since sleep disruption and next-day fogginess are common delayed signs.
Red Flags That Need Emergency Care
Most concussions are manageable at home with medical guidance, but certain symptoms signal something more serious, like bleeding or swelling in the brain. Get to an emergency room immediately if your child shows any of these:
- Repeated vomiting (not just once)
- Seizures or convulsions
- One pupil larger than the other
- Increasing confusion or disorientation
- Loss of consciousness lasting more than a brief moment
- Worsening headache that doesn’t improve
- Slurred speech or weakness in arms or legs
- Inability to recognize people or places
- Inconsolable crying that won’t stop (in infants)
- Refusal to eat or nurse (in infants)
These symptoms can appear right after the injury or develop over the following hours. If you’re unsure whether what you’re seeing is serious, err on the side of getting evaluated.
How Concussions Are Assessed
There’s no single blood test or scan that definitively diagnoses a concussion. Doctors rely on a combination of symptom reports, physical examination, and standardized assessment tools. For children ages 8 to 12, clinicians often use a tool called the Child SCAT6, which tests memory, concentration, balance, and coordination through a series of structured tasks. It includes things like timed balance stances, tandem walking (heel to toe in a straight line), and questions about symptoms.
A CT scan or MRI isn’t routine for every concussion. These imaging tools are used when a doctor suspects a more serious injury, like a skull fracture or brain bleed. A normal scan doesn’t rule out a concussion, because concussions involve functional disruption in the brain that standard imaging can’t see.
Getting Back to School
Most children can return to school within 1 to 2 days of a concussion, but they’ll likely need temporary adjustments. The goal is to ease back in rather than jump straight to a full workload. The CDC recommends short-term classroom accommodations based on the type of symptoms your child is experiencing:
For thinking and memory problems, schools can reduce assignments to key tasks only, provide extra time on tests (limiting tests to one per day), supply class notes, and allow recording of classroom instructions. For physical symptoms like headaches and light sensitivity, accommodations include rest breaks, permission to visit the school nurse, sunglasses indoors or seating away from bright windows, and extra time between classes to avoid noisy, crowded hallways. For emotional changes, having a designated adult to talk to and a quiet space to decompress can make a real difference.
These supports are temporary. As your child improves, the school gradually removes them until they’re back to their normal routine.
Returning to Sports and Physical Activity
Children should not return to sports until they’ve been cleared by a healthcare provider and have completed a gradual, step-by-step progression. The CDC outlines a 6-step return-to-play protocol, with each step taking a minimum of 24 hours. Your child should only move to the next step if they have no new symptoms at the current one.
The progression starts with a return to regular daily activities like school (Step 1), then moves to light aerobic exercise like 5 to 10 minutes on a stationary bike or light jogging (Step 2). From there, it builds to moderate activity with more head and body movement (Step 3), then heavy non-contact drills like sprinting and full weightlifting (Step 4). Only at Step 5 does your child return to full-contact practice, and Step 6 is competition.
If symptoms return at any step, your child drops back to the previous level and waits another 24 hours before trying again. Rushing this process increases the risk of a longer recovery or a more serious second injury. For children and adolescents, the brain needs more time to heal than it does in adults, so patience during this progression is especially important.