Overview
Reactive high counts go away when the cause is treated.
Bone marrow causes can raise clot risk.
Symptoms
Common signs:
- High platelet count on a blood test
Less common
- Usually no symptoms
When to get medical care
Call 911Sudden face drooping, arm weakness, trouble speaking, or vision loss: call 911. Or chest pain or leg swelling.
Get care todayVery high count with headaches.
See a doctor soonHigh count on a repeat test.
Causes
Reaction to illness.
Does it spread or run in families?
- It isn't contagious. You can't catch it from someone else.
Possible complications
Diagnosis
Blood tests.
Tests
Tests, if needed:
- Blood count:
- Iron tests:
- Gene tests: If very high or lasting.
Treatment
Treat the cause.
Self-care
- Recheck after illness
Medicines
Medicines that may help:
| Medicine | Helps with | Good to know |
|---|---|---|
| Low-dose aspirin | Some bone marrow causes | Only if advised. |
OwieClear doesn't give doses: follow the label or your healthcare professional. Medicine names here are examples, not a full list.
Which doctor treats this
- Start with your primary care provider (family doctor or internist).
- They may send you to a hematologist (blood doctor).
Pregnancy and breastfeeding
- If you're pregnant or planning to be, tell your prenatal provider about this condition.
- Don't start or stop any medicine on your own. Some are safe in pregnancy and some need to be changed.
- Ask before taking any pain reliever. The FDA advises avoiding ibuprofen and naproxen after 20 weeks unless your doctor says to.
- Breastfeeding: Most medicines are fine, but ask. The NIH LactMed database lists what's known about each one.
Outlook
Usually goes away.
Research studies
Research studies test new ways to find and treat health problems. Some are looking for volunteers. Talk with your doctor before joining one.
Search ClinicalTrials.gov for studies on High platelet count (thrombocytosis)
Sources
Last updated 2026-11-12.