Dead Toenail? Now What?

Dayna Player Robinson
Jun 16
3 min read

Help!

My Toenail Looks Dead After Race Day 😬

What to Do When Your Nail Goes Black (or Falls Off) After a Marathon

So… you didn’t follow The Big 3 for toenail survival on race day:

Trim your nails
Wear the right shoes (with room!)
Do not wear cotton socks!

And now you’ve crossed the finish line with a PR and some blood in your shoes. 🙃

You’re not alone! One of my runners recently texted me:

Let’s walk through what’s happening—and what to do next.

What’s Actually Going On?

What you’re seeing is likely a subungual hematoma, aka a black toenail caused by repeated pressure or impact. That "dead" look is from bleeding under the nail or trauma to the nail matrix. It might:

Turn dark purple or black
Lift partially
Be tender or throb
Eventually fall off 😬

If it’s loose, it may come off in a few days… or even a few weeks. Fun surprise!

What to Do Right Now

✅ Leave It Alone (Mostly)

Don’t try to pull the nail off—even if it’s loose. Let it detach on its own to avoid infection or damaging the new nail coming in.

✅ Clean & Protect

Gently wash the area with soap and water. Apply antibiotic ointment and a breathable bandage, especially if the skin underneath is exposed or sensitive.

✅ Trim Only the Detached Part

If the nail is catching on socks, trim only the already-lifted area. Never cut into the live nail bed or surrounding skin.

✅ Use Toe Caps or Moleskin If You’re Still Running

This protects the area from rubbing inside your shoe. Gel sleeves or silicone toe caps are awesome if you're mid-training block and can’t stop running.

What Happens When It Falls Off?

Totally normal and not as scary as it sounds.

The nail bed underneath will look raw, pink, or reddish
It may ooze or scab slightly—keep it clean and covered
A new nail will start to grow from the base (cuticle area)
It could take 4–6 months to fully regrow
The new nail may grow in a bit thicker, ridged, or odd-shaped for a while

Watch Out For These Signs of Infection:

Redness or swelling around the nail
Pus or yellow discharge
Increasing pain or heat in the toe
Red streaks moving up the foot

If you see any of those, get it checked out.

Can You Run with a Missing Toenail?

Yes—with protection. Bandage it or use a toe sleeve, and wear roomy shoes. Keep it padded and dry, and avoid super technical or rocky terrain until it heals a bit.

Want to Avoid This Next Time?

Here’s the checklist to save your toenails:

✅ Trim your nails a few days before race day (straight across!)

✅ Make sure there’s a thumb’s width of space in your toe box

✅ Use a heel lock lacing technique so your foot doesn’t slide forward

✅ Wear synthetic, moisture-wicking socks with no seams

Even experienced runners lose a toenail now and then—especially after fast or downhill-heavy races. It’s not a badge of shame, but it is a sign to check your gear before the next one!

If your toenails are looking rough post-race, send me a pic (I’ve seen it all 😅), and we’ll make sure you're set up to recover properly.

P.S. If you’ve lost a nail and still need to train, reach out—I’ll help adjust your plan so you can stay on track without making it worse.

Let those toes breathe, runners!

Let’s chase your version of awesome.

Happy running

Dayna - your fav. Exercise Physiologist & Run Coach