Symptoms often start mild and build slowly over years. Watch for these seven signs.

1. Swelling in Your Ankles and Lower Legs

Swelling (edema) is often the first sign of venous disease. It’s usually worse at the end of the day or after long periods of standing or sitting, and it improves overnight or when you raise your legs. You may notice sock lines pressed into your skin or shoes feeling tight by evening.

Leg swelling has other causes too, including heart failure, kidney disease and some medications. That’s why new or persistent swelling deserves a medical evaluation.

2. Aching, Heavy or Tired Legs

Many people with venous disease describe a dull ache, throbbing or heaviness in their calves. Their legs feel tired, as if they’ve been standing all day even when they haven’t. Like swelling, these symptoms typically get worse as the day goes on and improve with walking or putting your feet up.

3. Varicose Veins and Spider Veins

Varicose veins are enlarged, twisted veins that bulge under the skin, usually on the calves or the inside of the legs. Spider veins are smaller red, blue or purple veins close to the skin’s surface. Spider veins are often only a cosmetic concern. Varicose veins, however, are frequently a sign of faulty valves in deeper veins and can cause pain, swelling and skin changes.

4. Skin Discoloration Around the Ankles

When blood pools in the legs, red blood cells leak into the surrounding tissue. Over time, this causes reddish-brown or rust-colored patches, usually around the ankles and lower shins. Discoloration is a sign that venous disease has been present for a while and that the skin is under strain.

5. Itchy, Dry or Thickening Skin

Venous disease can cause stasis dermatitis, a type of eczema that makes the skin of the lower legs red, scaly and itchy. In more advanced stages, the skin can become hard, tight and shiny, a condition called lipodermatosclerosis. Scratching irritated skin can lead to breaks in the skin and infection.

6. Leg Cramps and Restless Legs at Night

Nighttime calf cramps and an uncomfortable urge to move your legs are common in people with venous disease. Many patients find these symptoms improve after vein treatment. Because cramps also have other causes, including dehydration and certain medications, it’s worth mentioning them to your doctor.

7. Wounds That Won’t Heal

A sore near the inner ankle that doesn’t heal within a few weeks may be a venous leg ulcer, the most advanced stage of chronic venous insufficiency. Venous ulcers are usually shallow, with irregular edges, and may weep fluid. They need prompt evaluation, because treating the underlying vein problem is key to healing them and keeping them from coming back.