Discoloration in Your Nails: Which Colours Mean You Should See a Doctor

Nail discoloration can be unsettling, but it’s often harmless. Nails may change colour for many reasons—from simple trauma to underlying health issues. Understanding what causes discoloration in nails and which changes warrant professional attention can help you stay informed without unnecessary anxiety.

What Causes Discoloration in Nails?

Several factors can alter the colour of your nails. Common causes include:

• Trauma or injury
  A bruise under the nail (subungual hematoma) can appear black, blue or red.

• Fungal or bacterial infections
  Onychomycosis (fungal infection) often turns nails yellow or white. Pseudomonas bacteria can cause a greenish tint.

• Systemic diseases
  Conditions like liver disease, kidney failure, respiratory issues or diabetes can show up as nail colour changes.

• Nutritional deficiencies
  Lack of vitamins and minerals (e.g., iron deficiency anemia) can lead to pale or white nails.

• Medications and chemicals
  Some antibiotics, chemotherapy drugs, or frequent use of nail polish and acetone can stain nails grey or yellow.

• Genetics and aging
  As we age, nails may naturally thicken or develop ridges and slight colour shifts.

When Nail Colour Changes May Be Harmless

Before diving into concerning colours, note that minor, isolated changes are often no cause for alarm:

• A small white streak from a mild bump
• Temporary yellow tint from dark nail polish
• Slight pinkness from temperature changes

If the change resolves in a few weeks without other symptoms, it’s likely benign. However, persistent or widespread changes—especially when paired with pain, swelling or general illness—should prompt a closer look.

Nail Colours That Warrant a Doctor’s Visit

Below is a guide to common nail discolourations and when you should consider professional evaluation.

White Nails

• Possible causes
  • Leukonychia (white spots or lines) from minor trauma
  • Liver disease (e.g., cirrhosis) when most of the nail is white
  • Kidney failure or congestive heart failure in severe cases

• When to see a doctor
  • Whole nail plate turns white and doesn’t grow out
  • You have fatigue, swelling in legs or other unexplained symptoms

Yellow Nails

• Possible causes
  • Fungal infection (onychomycosis)
  • Psoriasis
  • Yellow Nail Syndrome (rare, associated with respiratory issues and lymphedema)

• When to see a doctor
  • Persistent yellowing despite at-home antifungals
  • Thickened, crumbly nails or pain
  • Chronic cough or shortness of breath

Blue or Green Nails

• Possible causes
  • Pseudomonas bacterial infection (green nail syndrome)
  • Cyanosis (blue nails indicating low oxygen in blood)
  • Certain medications (e.g., amiodarone)

• When to see a doctor
  • Greenish discolouration that spreads or smells foul
  • Blue nails accompanied by breathing difficulties, chest pain or dizziness

Brown or Black Nails

• Possible causes
  • Subungual hematoma (blood under the nail) from trauma
  • Melanonychia (brown/black streaks) from benign moles or melanoma
  • Medication side effects (e.g., chemotherapy agents)

• When to see a doctor
  • A single dark streak running from the cuticle to the tip
  • Nail pain or persistent bruising without injury
  • Changes in the size or shape of brown/black patches

Red or Pink Nails

• Possible causes
  • Splinter hemorrhages (tiny blood clots) linked to trauma or endocarditis
  • Psoriasis or connective tissue disorders
  • Drug reactions

• When to see a doctor
  • Red streaks under the nail that don’t grow out
  • Fever, chills or signs of systemic infection
  • Joint pain or swollen fingertips

Purple Nails

• Possible causes
  • Subungual bleeding or blood dyscrasia (bleeding disorders)
  • Trauma leading to a deep bruise
  • Vascular issues (e.g., vasculitis)

• When to see a doctor
  • Purple or dark spots that persist for more than a few weeks
  • Bruising elsewhere on the body without clear cause
  • Signs of poor circulation (numbness, cold fingertips)

Grey Nails

• Possible causes
  • Long-term use of certain medications (e.g., antimalarials)
  • Heavy metal poisoning (e.g., arsenic, silver)
  • Fungal infection or chronic dermatitis

• When to see a doctor
  • Gradual greying over many nails
  • Accompanying rash, itching or swelling around the nail

Steps to Take at Home

1. Practice good nail hygiene:

   • Keep nails trimmed and clean.
   • Avoid harsh chemicals and limit nail polish use.

2. Monitor changes:

   • Take photos and note if the discolouration spreads or intensifies.
   • Track any new symptoms, such as pain or swelling.

3. Try basic remedies for mild cases:

   • Antifungal treatments for yellow nails.
   • Warm soaks and gentle cleaning for greenish nails.

When to Use an Online Symptom Checker

If you’re unsure whether your nail changes are serious, consider a free, online symptom check, using the doctor approved Ubie Symptom Checker. It can help you decide if you need immediate medical attention or can safely monitor your nails at home.

free, online symptom check, using the doctor approved Ubie Symptom Checker

Don’t Ignore Serious Signs

Some nail discolourations can be early indicators of serious conditions:

• Dark streaks that widen or new pigmented bands
• Widespread nail colour changes coupled with fatigue, weight loss or swelling
• Nail bed infections with pus, severe pain or spreading redness

If you experience any of these, speak to a doctor right away. Early diagnosis and treatment can be critical.

Key Takeaways

• What causes discoloration in nails ranges from minor injuries to systemic diseases.
• Most nail colour changes are harmless and resolve on their own.
• Persistent or widespread discolouration, especially with other symptoms, requires medical evaluation.
• Use the Ubie Symptom Checker for guidance on when to seek care.
• Always speak to a doctor about anything that could be life threatening or serious.

Staying informed about nail health empowers you to seek help when it matters most—without unnecessary worry. If in doubt, trust your instincts and consult a healthcare professional.