New or worsening symptoms after a concussion: when to seek medical help
Sort a new or changing symptom into 911, a call today or your next visit
You are several weeks into your recovery and have learned the rhythm of your symptoms. Then something shifts. The headache feels different, or your sister says you sounded confused on the phone.
It is hard to know what to do. You do not want to spend a night in the emergency room over a bad day, and you do not want to miss something serious.
This article sorts changes into three groups: call 911 now, call your care team today, or bring it up at your next visit. It draws on emergency lists from the CDC and from guidelines written in the US, Canada and England. It also covers the added risk that comes with older age or blood thinning medicine, and it gives you a simple log for tracking what changed.
Three levels of response
Most changes during a long recovery fall somewhere between an ordinary rough patch and an emergency. Putting each one in the right group helps you act fast when it matters and rest easier when it does not.
- Call 911 now. These signs can point to a serious problem that needs urgent assessment [3]. Do not drive yourself.
- Call your care team today. These changes need a clinician to weigh in within hours. If you cannot reach anyone, go to urgent care or an emergency department.
- Raise it at your next visit. These are changes worth tracking and talking through, such as symptoms that stall, or that flare with activity and then settle.
Your care team should prepare you for this. The NICE head injury guideline, written for the health service in England, asks clinicians to warn people that some who seem to bounce back quickly run into problems later [7]. It also says people should learn who to contact about lasting or delayed symptoms [7]. The Living Concussion Guidelines from Canada likewise call for teaching patients to watch for complications that need a recheck [8]. If no one has told you whom to call after hours, ask at your next visit.
Danger signs that need 911 or the ER without delay
The CDC advises emergency care right away for an adult with any of these danger signs [1]:
- A headache that worsens and doesn’t go away
- Weakness, numbness, decreased coordination, convulsions or seizures
- Repeated vomiting
- Slurred speech or unusual behavior
- One pupil larger than the other one (pupils are the black centers of the eyes)
- Acting confused, restless or agitated, or no longer recognizing people or places
- Loss of consciousness, looking very drowsy, or cannot be woken up
Other urgent signs in clinical guidelines
The 2025 Action Collaborative guideline, written for primary care, strongly recommends sending adults back to the emergency department for a set of warning signs [3]. Beyond the CDC list, it names alertness that drops or comes and goes, and a marked change in behavior such as extreme agitation [3]. It also lists signs of a skull fracture that was missed: bruising around both eyes, bruising behind an ear, or fluid draining from the nose or an ear [3].
The VA and Defense Department guideline adds double vision and new problems with movement or feeling to its list for immediate referral [2]. If you notice any of these, treat them the same way as the CDC danger signs.
The triage table: where does this change belong?
Use this table to decide how fast to act. Find the row that best fits what you see. If a change fits more than one row, follow the faster one.
Comparison compiled by Safety Behind the Wheel Foundation
Where does this change belong?
| What you notice | What to do |
|---|---|
| Any CDC danger sign in the box above | Call 911 now |
| Face drooping, one arm drifting down, or garbled speech | Call 911 now |
| New double vision, or new weakness or numbness | Call 911 now |
| Bruising around the eyes or behind an ear, or fluid leaking from the nose or an ear | Go to the emergency department now |
| Thoughts of suicide that are new or much stronger | Call or text 988; call 911 if in danger |
| A new hit to the head while on a blood thinner other than aspirin alone | Go to the emergency department now |
| Weeks after a bump: new confusion, weakness, numbness or clumsy walking | Call 911 now |
| Weeks after a bump: memory that slowly gets worse | Call your clinician right away |
| New neck pain together with headache or dizziness after a crash | Call your clinician today; 911 for any stroke sign |
| Low mood, panic or worry that is new or clearly worse | Call your clinician within days, the same day if severe |
| A new symptom that first appears more than 30 days after the injury | Book a visit soon to look for other causes |
| Taking pain relievers on many days each month | Raise it at your next visit, sooner if headaches come more often |
| Symptoms that flare with activity and settle with rest | Raise it at your next visit |
| Symptoms that still limit you after one month | Raise it at your next visit and ask about referral |
Sources: CDC [1]; MedlinePlus stroke and chronic subdural hematoma pages [9, 4]; VA/DoD [2]; Action Collaborative guideline [3]; NICE NG232, England [7]; Living Concussion Guidelines [10, 6, 8, 11]; 988 Lifeline [12]; EB Medicine review [13]. This is a general guide. When in doubt, call.
Imagine a 33 year old courier whose bike was clipped by a van turning right. Two months later his headaches are steady but familiar. He has started taking pain relievers almost every day, and the headaches seem to come sooner each morning. No single headache keeps building, and he has no other warning signs. This belongs at his next visit, or in a call this week if the headaches come even more often. He brings a log showing how many days he took pills.
Older adults, blood thinners and slow bleeds
A chronic subdural hematoma is an old pool of blood and broken down blood that collects between the brain and its outer covering [4]. With age, the brain shrinks a little, which stretches small veins and makes them easier to tear, even after a minor knock [4]. You or your family may not recall the bump at all [4]. Symptoms can begin right away or build slowly over a few weeks [14]. In older adults, new confusion, weakness or numbness can appear weeks or even months after the injury [4].
What the research shows
- A Swiss national study looked at 663 people who had surgery for this kind of bleed in 2013. Their median age was 76 [15].
- The yearly rate in that study was 8.2 per 100,000 people overall and rose to 64.2 per 100,000 among people in their 80s [15]. Only people who had surgery were counted, so bleeds treated without surgery are not in these numbers.
- Before they were admitted, 27.3% took aspirin regularly and 21.8% took a warfarin type blood thinner, two kinds of medicine that slow blood clotting [15].
- Trouble walking was the most common sign in these surgical patients, seen in 58.6%. Headache came next at 46.4%, then weakness or other focal problems at 40.7% and declining thinking at 39.8% [15].
- An older study of 354 people treated with surgery at one Swiss hospital from 1996 to 2002 found that 69% were 65 or older and 77% reported a fall beforehand [16]. Four in ten (41%) were taking drugs that slow clotting [16].
- A case control study of emergency patients over 60 at one academic hospital, seen from 2001 to 2010, linked anticoagulants with about 2.5 times the odds of this bleed. Antiplatelet drugs carried about 1.4 times the odds [5]. This shows a link, and the design cannot prove the drugs caused the bleeds.
What this means for you
In England, NICE tells phone advice services such as NHS 111 to send people with a head injury to an emergency department in certain cases [7]. One of them is taking an anticoagulant or antiplatelet drug, unless it is aspirin alone [7]. For people on anticoagulants with no other reason for a scan, NICE says clinicians should consider a CT scan within 8 hours of the injury [7]. The Living Concussion Guidelines say older adults taking warfarin type medicines should have brain imaging right away after a concussion [17].
A first scan that comes back normal is reassuring. For older adults on these drugs, the Living guidelines advise against routine repeat scans or hospital observation after a negative CT [17]. The late signs above still matter, though. The bleed can also return after surgery to drain it [4]. In the Swiss hospital study, 13.6% of patients had a recurrence [16].
Most concussions in adults over 65 come from falls, and often no one sees the fall happen [17]. When an older person develops new balance or vision problems, the Living guidelines ask clinicians to consider a concussion as a possible cause [17]. Never stop or change a blood thinner on your own. Tell the person who prescribes it about every fall or bump to the head.
Imagine a 74 year old retired teacher who takes a blood thinner for an irregular heartbeat. She was a passenger in a crash in June and slowly improved. In August she slips in her garden, bumps her head and feels fine. Three weeks later her husband notices that she shuffles, drops her coffee cup and repeats questions. These match CDC danger signs, so he calls 911 that morning.
Other causes that can look like a concussion setback
A new symptom after the first month
Some symptoms appear for the first time past the 30 day point after a mild TBI. For these, the VA and Defense Department guideline suggests a symptom by symptom search for some other cause [2]. Chronic pain, depression, anxiety and sleep disorders can all produce symptoms that resemble a concussion [6]. Medicines matter too, so bring a full list [6].
Stroke
Stroke symptoms usually come on suddenly and without warning [9]. They include weakness on one side of the face or body, trouble speaking or understanding speech, sudden loss of vision or double vision, a spinning feeling, and loss of balance [9]. Use the F.A.S.T. check. Face: ask the person to smile and look for a droop on one side. Arms: have them lift both arms and watch whether one sinks. Speech: ask them to repeat a short sentence and listen for slurring [9]. Time: call 911 at once, and note when symptoms began, since clot treatment must start within 4.5 hours [9].
A neck artery injury after a crash
Blunt force in a crash can sometimes tear one of the arteries in the neck. A review for emergency clinicians puts the rate at about 1% of adults admitted to a hospital after blunt trauma [13]. Symptoms may be delayed, and the common ones are headache, neck pain and dizziness [13]. Those are the same symptoms many people expect after a concussion. Traumatic tears cause up to 20% of strokes in adults younger than 45 [13]. If new or unusual neck pain arrives with headache or dizziness, tell your care team that day, and call 911 for any stroke sign.
Pain relievers that keep headaches going
Taking headache medicine often may make headaches more frequent and harder to shake [10]. When a headache after a head injury lasts, the international headache criteria tell clinicians to consider medication overuse headache [18]. The Living Concussion Guidelines advise clinicians to keep over the counter pain relievers to fewer than 15 days a month. Combination products with caffeine or codeine should be used on fewer than 10 days [10]. If your log shows more than that, raise it with your care team. Keep taking medicines as prescribed until your team plans any change with you.
When your mood is what changed
Shifts in mood and sleep sometimes surface one to two weeks later [1]. The Living Concussion Guidelines ask primary care to spot and treat changes in mood as part of concussion recovery [11]. When symptoms are severe or include a risk of suicide, the same guidelines call for referring you at once to a licensed mental health professional [11]. The 2025 guideline strongly recommends screening for mental health conditions that are new or have worsened after a TBI [3]. It adds that suicidal thinking that starts or intensifies after the injury may call for an emergency visit [3].
If sadness, worry, panic or irritability is new or getting worse, call your clinician within a few days. Tell them how long it has lasted and what it stops you from doing. You do not need to wait for a crisis to ask for help.
If you are thinking about suicide
A long recovery can drain anyone. If your thoughts turn to suicide or self harm, dial or text 988 for the Suicide and Crisis Lifeline. Its website, 988lifeline.org, offers chat as well. Veterans who dial 988 can press 1 for the Veterans Crisis Line, and texting 838255 also works [12]. For Spanish, the option is 2 [12]. If you might act on these thoughts soon, or anyone is in danger, call 911. Reaching out is a strong and sensible step.
Keep a record of what changed
Guidelines ask clinicians to track symptoms on a standard scale at each follow up visit until they improve or level off [6]. Your own record makes that easier and helps you spot a true change. Start by writing down what your usual looks like today. Include your top symptoms rated from 0 to 10, how long you can read or walk, and how you sleep.
Worksheet from Safety Behind the Wheel Foundation
Change log
| Date and time | What changed | Compared with my usual | What I did |
|---|---|---|---|
Bring this log to every visit. If a change matches a 911 sign, call first and write it down later.
Set up before you need it
Checklist from Safety Behind the Wheel Foundation
- Write your usual symptom levels on one dated page
- List every medicine, and circle any blood thinner or antiplatelet drug
- Save your clinic’s after hours number in your phone
- Know the route to the nearest emergency department and who could drive you
- Show one person in your home the danger signs and the F.A.S.T. check
- Keep the change log somewhere you will see it every day
Questions to ask your care team
Question checklist from Safety Behind the Wheel Foundation
- Which changes should make me call 911, and which should make me call you?
- What number should I call after hours or on a weekend?
- I take a blood thinner. What should I do if I fall or hit my head again?
- On how many days a month can I use my pain relievers?
- If a new symptom shows up after the first month, which other causes should we check?
- Which of my current symptoms do you expect to go up and down, and which would worry you?
- Should my mood be screened at each visit?
- Given my age, symptoms and medicines, would a scan help now?
Frequently asked questions
Can a concussion get worse weeks later?
By the CDC’s account, a couple of weeks is the usual time for a concussion to ease [1]. NICE notes that some people seem to recover fast and later have problems [7]. In older adults, a slow bleed can show up weeks or months after a bump [4]. A symptom that is brand new after 30 days may have another cause [2].
Could a bleed show up later if my first scan was normal?
A normal first CT is reassuring, and the Living guidelines do not call for routine repeat scans in older adults on blood thinners after a negative one [17]. A chronic subdural hematoma can still develop in the weeks that follow, so call 911 for new confusion, weakness or trouble walking [1, 4].
The bottom line
Recommendation from Safety Behind the Wheel Foundation
Most changes during a long concussion recovery can wait for a planned visit, especially flares that settle with rest [8]. Call 911 for any CDC danger sign or stroke sign, and treat new double vision, new weakness or fluid leaking from the nose or an ear the same way [1, 9, 3].
If you take a blood thinner other than aspirin alone, guidance in England counts a new hit to the head as a reason to go to an emergency department [7]. Ask your prescriber now what to do if you fall or bump your head. Older adults and anyone on these drugs should call 911 if confusion, weakness or unsteady walking appears weeks later [1, 4]. Get a fresh check for symptoms that start after 30 days [2]. Keep a simple change log, and call or text 988 if your mood turns dark [12].
Sources and further reading
- 1Centers for Disease Control and Prevention. Symptoms of mild TBI and concussion. Updated September 2025. cdc.gov/…/signs-symptoms/index.html
- 2U.S. Department of Veterans Affairs and Department of Defense. VA/DoD clinical practice guideline for the management and rehabilitation of post-acute mild traumatic brain injury, version 3.0. Provider summary. June 2021. healthquality.va.gov/…/VADoDmTBICPGProviderSummaryFinal508.pdf
- 3Silverberg ND, Lee K, Mikolić A, et al. Action Collaborative on Traumatic Brain Injury Care: adapted clinical practice guideline. Annals of Family Medicine. 2025;23(6):552-569. annfammed.org/content/23/6/552
- 4MedlinePlus (U.S. National Library of Medicine). Chronic subdural hematoma. Reviewed May 2026. medlineplus.gov/ency/article/000781.htm
- 5De Bonis P, Trevisi G, de Waure C, et al. Antiplatelet/anticoagulant agents and chronic subdural hematoma in the elderly. PLoS ONE. 2013;8(7):e68732. ideas.repec.org/a/plo/pone00/0068732.html
- 6Living Concussion Guidelines (Ottawa Hospital Research Institute). Diagnosis/assessment of prolonged symptoms. Updated April 2023. concussionsontario.org/…/diagnosis-assessment-of-prolonged-symptoms
- 7National Institute for Health and Care Excellence (NICE). Head injury: assessment and early management (NG232). Published May 2023. nice.org.uk/…/recommendations
- 8Living Concussion Guidelines (Ottawa Hospital Research Institute). Initial management. Updated August 2022. concussionsontario.org/…/initial_management
- 9MedlinePlus (U.S. National Library of Medicine). Stroke. Reviewed April 2025. medlineplus.gov/ency/article/000726.htm
- 10Living Concussion Guidelines (Ottawa Hospital Research Institute). Post-traumatic headache. Updated August 2022. concussionsontario.org/…/post-traumatic-headache
- 11Living Concussion Guidelines (Ottawa Hospital Research Institute). Mental health disorders. Updated April 2023. concussionsontario.org/…/mental-health-disorders
- 12988 Suicide and Crisis Lifeline. Get help. Accessed October 2026. 988lifeline.org/get-help
- 13Cadena R. Blunt cerebrovascular injuries: early recognition and stroke prevention in the emergency department. Emergency Medicine Practice (Stroke EXTRA). December 2020. ebmedicine.net/…/blunt-cerebrovascular-injuries
- 14NHS. Subdural haematoma. Page last reviewed July 2025. nhs.uk/conditions/subdural-haematoma/causes
- 15El Rahal A, Beck J, Ahlborn P, et al. Incidence, therapy, and outcome in the management of chronic subdural hematoma in Switzerland: a population-based multicenter cohort study. Frontiers in Neurology. 2023;14:1206996. frontiersin.org/…/full
- 16Baechli H, Nordmann A, Bucher HC, Gratzl O. Demographics and prevalent risk factors of chronic subdural haematoma: results of a large single-center cohort study. Neurosurgical Review. 2004;27:263-266. doc.rero.ch/…/10143_2004_Article_337.pdf
- 17Living Concussion Guidelines (Ottawa Hospital Research Institute). Older adults. Updated July 2025. concussionsontario.org/…/older-adults
- 18International Headache Society. ICHD-3: 5.2 Persistent headache attributed to traumatic injury to the head. Accessed October 2026. ichd-3.org/…/5-2-persistent-headache-attributed-to-traumatic-injury-to-the-head
This article reflects the safety priorities of concussion recovery and road safety education. It offers general education, not medical advice, and it cannot decide whether your own symptoms are an emergency. In any doubt, call 911 or your local emergency number. Check official sources such as the CDC, and talk with your own care team about your situation. Reviewed October 2026.
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