What to do after a head injury if you take blood thinners
An emergency physician and a clinical pharmacist share what to watch
A crash can cause bleeding inside the head, even without a cut you can see. If you take a medicine that slows clotting, a blow to the head can be more worrying. These drugs include anticoagulants such as warfarin or apixaban. They also include antiplatelet drugs such as clopidogrel. Tell the emergency team exactly which medicine you take, the dose and when you last took it. Do this even if you feel fully alert. [1]
What happens at the first exam
The team weighs your symptoms, exam results and medicines. Then they decide whether you need a CT scan of your head. Sometimes the scan shows no bleeding. Your exam may also match how you normally are. When both are true, not every adult needs a routine hospital stay or a repeat scan. Other injuries you have, or your own situation, can change that call. [1]
Ask why it’s safe for you to go home and who should watch you for changes. Find out if you need advice about your medicine from whoever prescribed it. [1]
Delayed warning signs to take seriously
A bleed that shows up later is uncommon. Even so, you need to watch for one. Call emergency services for a headache that gets worse and won’t go away or for repeated vomiting. New weakness, confusion, slurred speech or a seizure also means calling. So does strange behavior or being hard to wake up. [1, 2]
Don’t wait for your next appointment. Keep your written discharge instructions where you and someone you trust can find them. [1, 2]
Get clear on your medicine plan
Do not change your blood thinner on your own. Ask whether to take your next dose as usual. Find out who to call if another doctor tells you something different. If falls or repeat head injuries are a worry, set up a later talk about the medicine’s benefits and risks. [1]
Questions to ask before you leave
- What did my exam and scan show?
- What exactly should I do about my next dose?
- Which symptoms mean we should call emergency services?
Snap a photo of your medicine list
Take a picture of your medicine list. Share it with the team treating you. [1]
Sources and further reading
- 1American College of Emergency Physicians, mild head injury policy
- 2Centers for Disease Control and Prevention, concussion danger signs
This is general education from emergency medicine and pharmacy. A doctor needs to weigh your head injury and medicine risks for you as an individual. Never stop or restart a prescribed blood thinner on your own.
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