Fingernails looking a little funky these days? It could be a sign something’s up with your health. Changes in your fingernails and toenails can actually be a sign of a serious illness like rheumatoid arthritis (RA).

RA is an autoimmune condition that attacks joints — usually in your hands, wrists, and knees. This causes inflammation of the joint lining and tissue damage that leads to chronic pain and joint damage. This tissue damage can also target your organs.

Nail changes may signal a problem before other RA symptoms show up. If you have RA, the color, shape, or surface of your nails — and even the way your nails attach to your skin — can change.

People who live with RA experience periods of flare-up and remission of symptoms. If left untreated, RA can permanently damage your bones and joints.

Yellow nail syndrome

According to the American Academy of Dermatology Association, RA may cause nails to turn yellow. A type of medications called thiol drugs, which are used to treat RA, may also contribute to nail yellowing.

With yellow nail syndrome, nails become yellow, thicker, and curved. Nails may also stop growing, and the cuticles can disappear. Worst-case scenario, nails separate from the nail bed and fall out. This can lead to an infection of the tissue around your nails.

Longitudinal ridging

Onychorrhexis — aka longitudinal ridging — occurs when grooves develop that run the length of your nails, from base to tip. Ridges like these can be a symptom of RA.

Deep ridges may cause a fissure where the nail splits lengthwise. Regardless of the cause of ridging, fissures or any damage to the nail bed can make you susceptible to infection.

Splinter hemorrhages

A splinter hemorrhage is a small brown, black, or reddish line or spot under your fingernail caused by tiny inflamed blood vessels leaking under the nail. It looks sort of like a splinter stuck under your nail and usually isn’t painful.

Splinter hemorrhages can result from an injury to the nail, but they can also be a sign of systemic disease. If you notice splinter hemorrhages on multiple nails without any evidence of injury, they could be a symptom of RA.

Other potential changes

While they’re not as common, keep an eye out for these nail changes if you’re having other symptoms of RA or are at greater risk of RA:

  • Capillary changes. Capillaries under and around nails may become enlarged or deformed or bleed. Doctors can examine with a magnifying dermascope to see problems that aren’t visible to the eye.
  • Clubbing. Nails may grow in a downward curving shape, sometimes causing the fingertips to swell and appear club-like. This can also be a sign of heart disease, lung disease, or liver disease.
  • Onycholysis. Nails may separate from the nail bed and turn white or yellow. This is more common in psoriatic arthritis (PsA).
  • Nail bed telangiectasia. Spider veins that look like red or pink lines may develop in the skin around your nails.
  • Brittle nails. Nails may become weaker and break more often. Brittle nails can also be caused by nutrient deficiencies and other systemic conditions.
  • Pterygium. The skin where your nail emerges may grow over the nail area. This is often related to connective tissue diseases.
  • Palpable purpura. Raised hemorrhages in the skin around the nails can happen as a result of RA’s inflammation of blood vessels.
  • Nailfold infarcts. Small brown spots may appear on skin around nails.

RA and PsA are both autoimmune conditions that cause joint pain and nail changes. So what’s the diff?

PsA is a mixture of psoriasis and arthritis symptoms that often hits that last finger joint the hardest. Not everyone with RA has nail-related symptoms, but folks with PsA are much more likely to have skin and nail symptoms. In fact, about 80 percent of people with PsA experience nail changes.

People with PsA are also more likely to experience nail pitting and more painful nail splitting that can lead to infections. Ridges and nail separation can also occur.

To treat RA nail changes, you have to treat the disease first. Doctors may prescribe medications such as disease-modifying antirheumatic drugs and biological response modifiers (also known as biologics) to help treat RA symptoms.

Your doc may recommend other lifestyle changes to help reduce and manage RA symptoms, such as:

  • Exercising. You could try walking, swimming, or biking for 30 minutes per day, 5 days per week.
  • Taking movement classes for arthritis. Some gyms and community centers have classes focused on the mobility and pain management needs of people with joint problems.
  • Trying to quit smoking. A history of smoking may increase your risk of developing RA, and continued smoking may make symptoms worse.
  • Getting enough rest. Give yourself a break. Too much stress may contribute to symptoms.
  • Changing your diet. Eating more foods that reduce inflammation may help your symptoms.

Changes in your nails can be a signal of a number of underlying health conditions. So if you notice changes in your nails, it’s worth having a conversation with a doctor or dermatologist ASAP.

Also see a doctor if any of your nails seem infected. Look for swelling, redness, pus, and pain. An infection may require treatment with antibiotics or other medication.

If you have other symptoms that point to RA, let your doctor know and ask about seeing a rheumatologist. The earlier you get an RA diagnosis, the sooner you can start managing your symptoms.

RA is an autoimmune disease that attacks joints and causes pain. It can also cause some nail changes like yellowing, ridging, hemorrhages, and nail separation.

If you notice your nails changing in shape or color, make sure to talk with a doctor. Sometimes nail symptoms show up before other RA symptoms, and noticing them can help you start treatment early.