Lingering Concussion Symptoms After a Car Accident

By Nova Physical Therapy, an outpatient physical therapy clinic in North Hollywood, CA | Published November 2026

It's been a few weeks since the accident. The car is fixed, but you're not. You still get headaches by midafternoon, the grocery store lights feel too bright, turning your head quickly makes you dizzy, and you lose your train of thought in meetings. You start wondering if this is normal, or if something was missed.

Concussion symptoms after a car accident often improve within days to weeks, but for some people they linger. This article explains what a concussion is, why symptoms can last, when to see a physician, how physical therapy can help once you've been medically evaluated, and which warning signs need emergency care.

The short answer

A concussion is a mild traumatic brain injury caused by a blow or a fast jolt to the head, including the whiplash motion of a car crash. Symptoms can affect the body, thinking, and mood, and the most common lingering ones are headaches, dizziness, balance problems, and vision problems (APTA ChoosePT). Any suspected concussion should be evaluated by a physician first, and symptoms lasting more than about three weeks deserve further evaluation and treatment (APTA ChoosePT). The APTA concussion guideline supports physical therapy for problems in four areas: the neck, the vestibular and eye-movement systems, exercise tolerance, and balance and movement (guideline summary; Quatman-Yates et al., 2020). In California, you can see a physical therapist without a referral, but with a head injury, a physician's evaluation comes first.

What does a concussion feel like?

Symptoms can start right away or show up hours to days later (APTA ChoosePT):

• Physical: headache, dizziness, balance problems, nausea, fatigue, sleep changes, blurred or double vision, and sensitivity to light and noise
• Thinking: trouble concentrating or remembering, feeling slowed down or "foggy"
• Emotional: irritability, anxiety, low mood, or mood swings

You don't have to hit your head or lose consciousness to have a concussion. The rapid back-and-forth movement in a crash can be enough.

Why do concussion symptoms last?

Many people improve within a few weeks. When symptoms linger, they often come from specific problems that can be checked and treated:

• The neck: a neck injury from the same crash can cause headaches and dizziness
• The inner ear and eye movements: problems coordinating the eyes, head, and balance system are among the most common lingering issues (guideline summary)
• Exercise tolerance: symptoms that flare with physical effort
• Balance and movement: unsteadiness or slower reactions

Too much rest and doing too much too soon can both slow recovery (guideline summary). Sleep, stress, and other health factors play a role too.

When should I see a doctor?

See a physician after any suspected concussion, and again if symptoms last beyond about three weeks or get worse (APTA ChoosePT).

Call 911 or go to the emergency room if you have (CDC HEADS UP):

• A headache that gets worse and doesn't go away
• Repeated vomiting, convulsions, or seizures
• Slurred speech, weakness, numbness, or decreased coordination
• Unusual drowsiness or inability to wake up
• One pupil larger than the other
• Increasing confusion, restlessness, or agitation

Physical therapists screen for these signs and refer to a physician when they find them (guideline summary).

How can physical therapy help with lingering symptoms?

After a physician's evaluation, physical therapy can address the specific problems behind lingering symptoms. A physical therapy evaluation may include:

• Your symptoms, what triggers them, and your daily demands
• Neck motion, strength, and tenderness
• Eye movements, gaze stability, and dizziness testing
• Balance and coordination
• A carefully monitored exercise tolerance test

Based on the guideline, a plan may include (guideline summary; APTA ChoosePT):

• Gradual, symptom-guided aerobic exercise, such as stationary cycling, progressed over time
• Neck treatment: motion and strengthening exercises and hands-on treatment
• Vestibular rehab: gaze stability, eye movement, and balance exercises, plus repositioning maneuvers if a specific type of positional vertigo is found
• Activity pacing: a plan for gradually returning to work, driving, screens, and exercise

Physical therapy doesn't guarantee a specific result or timeline. Questions about medication, imaging, or other symptoms such as mood changes are best directed to your physician. We focus on your recovery; questions about insurance claims or legal matters are best directed to your insurer or attorney.

At Nova Physical Therapy in North Hollywood, auto accident injuries, including concussion-related symptoms, are one of our core services, and every plan starts with an evaluation so treatment fits what we find. For related reading, see our posts on whiplash recovery and headaches that start in the neck.

Do I need a referral for physical therapy in California?

Not to get started. California allows direct access to physical therapy. A physical therapist can evaluate and treat you without a referral for up to 45 calendar days or 12 visits, whichever comes first. After that, a physician or podiatrist needs to sign the plan of care for treatment to continue. Your insurance plan may have its own referral rules, so check your coverage or see our insurance page.

Frequently asked questions

Can you get a concussion without hitting your head?
Yes. The fast back-and-forth motion of a car crash can cause a concussion even without a direct blow or loss of consciousness.

How long do concussion symptoms last after a car accident?
Many people improve within days to a few weeks. Symptoms lasting beyond about three weeks should be evaluated further by a physician.

Should I rest completely after a concussion?
Only briefly. Guidance now favors a short rest of a day or two, followed by a gradual, symptom-guided return to activity. Too much rest can slow recovery.

Why do I still feel dizzy weeks after my accident?
Lingering dizziness often comes from the neck, the inner ear, or eye-movement coordination. A physician evaluation, then targeted physical therapy, can help sort it out.

Can physical therapy help post-concussion headaches?
Often, yes, especially when the neck is involved. Treatment may include neck exercises, hands-on treatment, and a graded exercise plan.

When can I drive or exercise again after a concussion?
Return gradually, with guidance from your physician and therapist, once symptoms allow. Stop and rest if symptoms clearly increase.

Do I need a referral to see a physical therapist?
Not in California, within the limits described above. With any head injury, see a physician first to rule out serious problems.

About Nova Physical Therapy

Nova Physical Therapy is an outpatient physical therapy clinic in North Hollywood, California, led by a Doctor of Physical Therapy. We help people recover from auto accident injuries, back and neck pain, sports injuries, work injuries, knee pain, and shoulder problems, and we also work with balance problems and rehab after surgery. Patients come to us from North Hollywood, Burbank, Studio City, Toluca Lake, Valley Village, and across the San Fernando Valley. Learn more about Nova or see our services.

Schedule an evaluation

If concussion symptoms are lingering after an accident and you’ve been checked by a physician, an evaluation can help find what’s driving them and build a plan.

Nova Physical Therapy
4795 Vineland Ave #E, North Hollywood, CA 91602
Call (818) 639-3402 | Book an appointment online

Disclaimer

This article is for general education only. It is not medical advice, a diagnosis, or a treatment recommendation for any individual. Head injuries can be serious, and any suspected concussion should be evaluated by a physician. Only an in-person evaluation can determine what is right for you. No treatment guarantees symptom resolution, and results vary. Physical therapists evaluate movement and function within their scope of practice and refer to physicians when findings warrant. Physical therapy in California is regulated by the Physical Therapy Board of California.

References

1. Quatman-Yates CC, Hunter-Giordano A, Shimamura KK, et al. Physical Therapy Evaluation and Treatment After Concussion/Mild Traumatic Brain Injury: Clinical Practice Guidelines. J Orthop Sports Phys Ther. 2020;50(4):CPG1–CPG73. Link
2. MedBridge. Concussion management strategies (summary of the 2020 APTA guideline). Link
3. American Physical Therapy Association. Physical Therapy Guide to Concussion. ChoosePT. Link
4. Centers for Disease Control and Prevention. HEADS UP: Concussion information sheet. Link