- High fever or serious infection
- Major emotional or physical stress/trauma
- Chemotherapy or certain medications
- Heart attack, very poorly controlled diabetes, or other systemic shocks
- Direct crush injury to the nail base
If you suddenly notice deep horizontal indentations on several nails, something significant stressed your body a few months ago. It’s worth a doctor visit to make sure everything is truly resolved.
Other Nail Changes That Should Send You to the Doctor—Fast
See a professional right away if you notice:
- New dark vertical streaks (possible subungual melanoma)
- Yellow-brown discoloration or thickening
- Nails lifting off the bed (onycholysis)
- Pain, redness, swelling, or pus around the nail
- Sudden splitting, peeling, or crumbling
- Multiple deep Beau’s lines appearing at once
How to Make Vertical Ridges Less Noticeable (and Keep Nails Healthier Overall)
If your ridges are the harmless kind, you can smooth them dramatically: