What Causes Legs to Turn Dark?

Noticed your legs looking darker than usual? Brownish patches around your ankles, purplish areas, or skin that’s changed color? It’s more common than you think and it often points to circulation issues that need attention.

Understanding Leg Discoloration

Leg discoloration happens when blood flow problems cause skin color changes. When veins struggle to push blood back to your heart, pressure builds in your lower legs. This causes small blood vessels to leak, releasing proteins and iron deposits that stain the tissue. Over time, these show up as brown, red, or purple patches, especially around the ankles and calves where blood tends to collect.

Here’s what could be causing it and when you should get it checked.

Deep Vein Thrombosis (DVT)

A blood clot in a deep leg vein blocks normal circulation, causing swelling, pain and a dark or purplish appearance. Even after treating the clot, some people develop post-thrombotic syndrome, which causes the discoloration to persist.

The condition needs immediate attention because clots can travel to your lungs. DVT treatment typically involves blood thinners and sometimes we use minimally invasive procedures to restore proper blood flow.

Peripheral Artery Disease (PAD)

PAD is different. It affects your arteries, not your veins. When plaque narrows the arteries, less blood reaches your legs. Your skin might look pale or dark and you could feel cramping, coldness, or pain when you walk.

After Rashes or Skin Irritation

Dark spots can show up after rashes, bug bites, or any kind of skin irritation. This is called post-inflammatory hyperpigmentation. These marks fade slowly, sometimes taking months, but they usually go away on their own.

Stick with gentle soaps, don’t scratch and keep your skin moisturized. If spots hang around too long, a dermatologist might suggest lightening creams or chemical peels.

Iron Deposits Under the Skin

When tiny blood vessels break or leak, small amounts of blood collect under your skin. As those blood cells break down, they leave iron deposits that look like rusty brown patches.

You’ll see this in conditions like Schamberg’s disease. It’s usually harmless and doesn’t need aggressive treatment. Keeping your legs moisturized and improving circulation can prevent it from spreading.

Sun Exposure and Medications

Long periods in the sun without protection may cause the skin on the legs to gradually become darker. Some medications may cause this as well, including selected antibiotics, birth control and anti-inflammatory medications.

If a medication is newly prescribed and you suspect it may be the cause, you should contact your physician. Using sunscreen daily will stop the skin from darkening and provide long-term protection.

When It’s Connected to Other Health Issues

In certain cases, darkened skin on the legs may indicate underlying severe medical conditions. Diabetes, heart disease and kidney disorders will affect blood circulation and may cause swelling and changes in skin color. Autoimmune diseases may cause blood vessels to become damaged and change the skin tone.

If you’re seeing discoloration along with swelling, numbness, or sores that won’t heal, get it checked out.

Who’s at Risk?

Certain factors increase your likelihood of developing leg discoloration:

• Adults over 50
• People who are overweight or inactive
• Those with high blood pressure or diabetes
• Anyone with untreated varicose veins
• History of blood clots, heart conditions, or previous leg surgery
• Smokers

Warning Signs That Need Attention

Symptoms for which you should seek medical help include:  

• Swelling that does not go away;  
• Legs that ache, become warm, or throb;  
• Skin that is tightly bound, shiny, or itchy;  
• Open sores or ulcers;  
• Darkening of the skin after an injury, especially sudden.  

These symptoms might indicate problems with your veins or arteries and should be addressed immediately to avoid serious complications.  

How We Diagnose It

The first visit is 45 to 60 minutes and consists of a discussion of the symptoms, medical history, a physical exam and possibly some tests. We assess blood flow and vein structure with a duplex ultrasound and measure circulation with the ankle-brachial index. Potassium, diabetes, inflammation and blood clotting disorders are checked in blood tests. Rarely, a skin biopsy is performed to rule out some other conditions. These tests indicate whether you have vein disease, inadequate circulation, or a skin disease.

Treatment Approaches

The severity and underlying causes determine the most suitable course of treatment. Initial steps may include the use of compression stockings for blood flow improvement and swelling reduction, as well as leg elevation during rest periods. Regular exercises such as walking and cycling can enhance blood flow for patients as well. Depending on the situation, blood thinners and diuretics may also be prescribed. 

For advanced cases, we may offer a range of procedural options. 

• The first procedure is sclerotherapy, where a solution is injected into the varicose veins which causes the veins to collapse and disappear. 
• For the second procedure, endovenous ablation, heat is used to close problematic veins and reroute blood flow. 
• Third, laser therapy for the treatment of varicose veins, it also improves skin color. 
• Lastly, severe cases and extensive skin damage may require skin grafting to promote healing.

Prevention Through Daily Habits

• Prevention can begin with incorporating daily habits like these:
• Engaging in physical activities instead of prolonged sitting or standing
• Consuming an array of fruits and vegetables with bioflavonoids (dark leafy greens, berries and citrus)
• Avoid gaining and maintaining excess weight
• Discontinue tobacco use
• Clean and refill with moisturizer
• Consistently apply and reapply sunscreen
• Refrain from tight and uncomfortable attire

Risks of Delaying Treatment

Overlooking the early signs of skin disorders may lead to larger and slower healing hypoxic skin ulcers or advancing infections. Increased pain may cause functional impairments as underlying vascular disorders may remain unaddressed and worsen. Chronic and persistent skin discoloration can create stigmas that negatively impact self-esteem and quality of life. People often avoid social and recreational activities to mask the condition of their legs, leading to feelings of depression.

Take the Next Step

Caring for discoloured legs goes beyond skin deep. Irregular skin patterns indicate vascular issues that require immediate treatment. Luckily, appropriate and timely treatment can fix most issues and prevent advanced problems.

If you’re dealing with dark patches, swelling, or discomfort in your legs, schedule a consultation with Prime Vascular Care. We’ll evaluate your blood circulation, explain your options clearly and create a treatment plan that fits your life.