Raynaud Syndrome Explained: More Than Cold Fingers and Toes

Raynaud syndrome (or Raynaud phenomenon or Raynaud disease, as it is also known) occurs when small blood vessels overreact to cold temperatures and stress. Instead of adjusting normally, the vessels spasm and narrow, limiting blood flow. The skin may change color and, in more extreme cases, more serious issues, such as skin ulcers and gangrene (tissue death caused by a loss of blood supply) can develop.

When people with this condition spend time outside in chilly weather—or inside in air conditioning—their fingers and/or toes may feel unusually cold and turn bluish or become pale white.

In truth, this can happen to any of us occasionally, and if your fingers, toes, or other temperature-sensitive areas quickly return to normal, it’s likely just your body reacting to the cold, and you may simply need warmer gloves or socks. But if it happens frequently and is painful, it’s worth considering whether you should consult an endocrinologist who can help determine whether you have Raynaud syndrome.

Raynaud phenomenon is named after the French physician who first described it. Exposure to cold can cause the affected areas to appear blue because of decreased oxygen. They may then turn white as the skin tissue uses up the remaining oxygen. When blood flow returns, the skin often turns red once the vessels relax and blood rushes back in.

During a Raynaud attack, blood vessels spasm and narrow instead of adjusting normally to temperature changes. As a result, blood flow to the skin is temporarily reduced.

Affected areas may change color in stages:

• White, as blood flow is restricted
• Blue, as oxygen levels drop
• Red, when blood flow returns and vessels relax

“This is the classic presentation, but not everybody experiences all three colors, and the order of the color changes can vary,” says Monique Hinchcliff, MD, MS, a Yale Medicine rheumatologist. “But it’s important to note it’s not just your fingers turning cold with a bluish tinge with cold exposure, which is normal. The color changes must be marked.”

Episodes can last from minutes to several hours, depending on severity and how quickly the area is rewarmed.

Raynaud phenomenon most commonly affects:

• Fingers
• Toes

But it can also involve other areas with small blood vessels, including:

• The nose
• The tip of the tongue
• Nipples
• The tip of the penis

“It’s essentially anywhere you have small blood vessels,” Dr. Hinchcliff explains.

When Raynaud affects the hands, it often involves more than one finger, though not always all of them. It may appear in the dominant hand, the nondominant hand, or both.

Blood flow in the skin is tightly regulated by nerve and hormone signals. Exposure to cold or emotional stress can trigger the release of chemicals that cause blood vessels to constrict.

Raynaud phenomenon is more common in women than men, particularly between the teenage years and about age 30, suggesting that hormones such as estrogen may play a role.

There are two forms of Raynaud phenomenon: primary and secondary.

Primary Raynaud phenomenon: This is the most common form, affecting up to 10% of the population. It occurs on its own, without an underlying disease.

“It’s harmless and just annoying,” Dr. Hinchcliff says. “People with this type don’t have a risk of digital ulcers forming and it doesn’t necessarily even need to be treated.”

Secondary Raynaud phenomenon: This is less common but typically more severe. It is associated with underlying conditions, most often autoimmune diseases such as:

• Scleroderma
• Lupus
• Polymyositis

In these conditions, immune-driven inflammation can damage small blood vessels, worsening Raynaud symptoms.

Secondary Raynaud can also occur in people exposed to repeated vibration, such as those who use jackhammers or chainsaws, which can injure blood vessels and nerves over time.

In severe cases, prolonged reductions in blood flow can cause:

• Persistent pain
• Skin ulcers
• Slow-healing sores
• Rarely, tissue damage or loss

Occasional cold fingers or toes that quickly return to normal are usually not a cause for concern.

“But when episodes happen consistently and involve visible color changes, Raynaud becomes more likely,” Dr. Hinchcliff says.

Doctors may diagnose Raynaud using a nailfold capillaroscopy, a test that examines tiny blood vessels at the base of the fingernails under a microscope.

“These are the tiniest vessels in our bodies and they can be viewed quite easily. And if those are completely normal and there's no evidence of small hemorrhages or other signs, the patient is diagnosed with primary Raynaud,” Dr. Hinchcliff explains. “But if the capillary exam is abnormal or there's positive anti-nuclear antibodies identified, which we do from a blood test, then that suggests that there may be an underlying autoimmune disease. And that would be when a patient would want to see a rheumatologist.”

There are no FDA-approved medications specifically for Raynaud phenomenon. However, doctors often prescribe medications off-label for secondary Raynaud, including:

• Calcium channel blockers, which help relax and widen blood vessels
• Certain medications used for erectile dysfunction, which also improve blood flow

For severe cases that don’t respond to standard therapies, Yale Medicine offers intravenous epoprostenol infusions, available at outpatient centers across the state.

For people with primary Raynaud phenomenon, treatment focuses on avoiding triggers and protecting circulation.

Strategies that may help include:

• Limiting exposure to cold and rapid temperature changes
• Managing stress
• Keeping the core body warm
• Using heated gloves, vests, or disposable heat packs

Certain medications can worsen Raynaud symptoms, including:

• Migraine medications (such as triptans)
• Stimulants used for ADHD
• Beta blockers

“If you have Raynaud, it’s important to review your medications with your primary care provider,” Dr. Hinchcliff says.

Avoiding nicotine and limiting caffeine can also help, as both constrict blood vessels.

Gentle, gradual warming is key. Dr. Hinchcliff recommends:

• Placing hands in the armpits
• Sitting on hands
• Running hands under warm—not hot—water
• Gently moving fingers and toes
• Letting arms hang down to use gravity
• Rubbing hands together to create friction

“You are trying to very slowly help the blood vessels relax, which will help avoid any pain,” Dr. Hinchcliff says.

No. Raynaud can be triggered year-round.

“Often, Raynaud is most problematic in places with a lot of air conditioning. And it seems to be going from one temperature to another. For example, if it's hot outside, and then you go into the grocery store where it's freezing, that can trigger an attack,” she says.

She advises patients to keep a sweater and gloves handy—even in summer.

Stress-related triggers may also respond to mindfulness and relaxation techniques. As Dr. Hinchcliff puts it, “An ounce of prevention can be a pound of cure.”