How long does a concussion last?
You’re not alone in wondering this.
There is a lot of information and misinformation surrounding concussion. With that, I wanted to answer this question while providing some context and cautionary notes that you likely haven’t heard before - even from the CDC.
The concussion timeline.
Impact - The concussion
This is where you actually sustain the impact that transmits enough force through the skull to “jostle” your brain and sustain a concussion. At this point, there are 3 key things that are happening in your body and brain:
“Functional” Nerve Cell Damage - Nerve cells (neurons) get stretched and sheared in a concussion. The damage is “functional” and NOT “pathological” because there is no damage visible in imaging studies in concussion/mTBI.
Excitotoxicity/Inflammation - When the neurons get stretched, they “leak,” and stimulatory molecules get scattered everywhere causing the random firing of neurons. The “dazed” feeling immediately after impact is thought to be due to this “random firing” of nerve cells after impact.
Energy Deficit - Following this whole “stretch, shear, excitotoxicity event,” the body has to clean up shop. Between the random firing and the clean-up, the brain burns through its energy stores. This eventually leads to an energy deficit. It’s thought that this energy deficit may correlate with symptoms - but, we’ll come back to that in a second. (Also, just for funsies, the brain also receives significantly less blood flow following a concussion, and that adds to the energy deficit.)
3-5 Days after impact
Following a concussion, your energy levels continue to nosedive (about 20%) for the next 3-5 days. This is often why people who sustain a concussion often feel their WORST around 3-5 days after their injury.
5-10 days after impact
Now, for most people, this is when symptoms start to go away and things start to feel normal again. This timeline is true for most concussions, however, up to 40% of concussion cases can go on to become post-concussion syndrome if not treated properly.
Does symptoms resolution mean the concussion is resolved? Not so fast, pal.
21-30 days after impact
Remember that whole energy deficit? Well, when we measure energy via NAA (a marker of ATP; energy) we see that it takes 21-30 days before brain ATP levels return to normal. This means that it takes around 3-4 weeks before your brain is back in business at pre-concussion energy (ATP) standards.
That brings us to our cautionary note…
Symptom resolution DOES NOT equal concussion resolution.
You may have noticed something up there:
Symptoms resolve in 7-10 days, in most cases.
Brain metabolism resolves in 21-30 days, in most cases.
Your concussion is not resolved until your brain is back in action.
We are gaining an understanding from the literature is that your brain is not fully back in action for at least 3-4 weeks after your concussion.
The potential risk of an early return.
Feeling good is great.
Feeling good AND being metabolically healthy is even better.
Remember that symptoms resolve before your brain metabolism resolves. With that in mind, it’s important to note that a second impact during your metabolic recovery can dip your metabolism even lower. The second metabolic dip may be more damaging to you than the first, and will certainly lead to a longer recovery time.
Post-Concussion Syndrome (PCS)
This is the label applied to the condition that those individuals who do not recover on this timeline experience. PCS is when concussion symptoms last beyond those predicted 7-10 days. More specifically:
Concussion symptoms lasting longer than 14 days (2 weeks) in adults.
Concussion symptoms lasting longer than 30 days (4 weeks) in children.
So, how long does a concussion last?
From the time of impact, an appropriate recovery is around 3-4 weeks.
Symptoms occur on or shortly after the impact.
Symptoms (and the energy deficit) are worst at around 3-5 days.
Symptoms may resolve in 5-10 days.
Brain metabolism usually resolves in 21-30 days.
PCS is diagnosed when symptoms go on longer than 2-4 weeks.
The good news is that there are things we can do to facilitate and speed recovery.
Dr. Mark Heisig is a licensed naturopathic doctor with continuing mTBI education from The American Academy of Neurology (AAN), Complete Concussion. Management (CCMI) and The Carrick Institute. His office is located in Scottsdale, AZ.