Answers

Can varicose veins cause lymphedema?

Yes. Years of venous pressure overload the lymphatics until they fail too (phlebolymphedema). Skin that darkens, thickens or stops pitting marks the change.

By The Renu lymphatic and massage team · 6 min read

Yes. Varicose veins on their own are rarely the cause, but the chronic venous insufficiency they can progress to is a recognised cause of secondary lymphedema. Years of high pressure in the leg veins push more fluid into the tissue than the lymphatic vessels can return, the vessels are overworked and eventually damaged, and the swelling becomes a combined venous and lymphatic condition that vascular specialists call phlebolymphedema. The Lymphoedema Support Network lists venous insufficiency from varicose veins or deep vein thrombosis among the causes of secondary lymphoedema, and the National Lymphedema Network has a phlebolymphedema position paper in preparation. Once the lymphatics are involved, management widens from compression alone to lymphatic drainage, skin care and the full decongestive programme.

Being told that your “vein legs” are now “lymphedema legs” is confusing, because nothing happened on a particular day. The veins did not change. What changed, slowly, is that the drainage system that had been compensating for them wore out. This page explains that process, the signs that mark it, and what it means for how the legs are looked after.

Two drainage systems, one of them overworked

Fluid leaves the small blood vessels into the tissue all the time, and two routes carry it back: the veins and the lymphatic vessels. The Lymphoedema Support Network describes the lymphatic system as the body’s waste disposal, taking tissue fluid, protein, bacteria and waste away from the tissues and returning it to the veins behind the collarbone. A recent educational paper in the Journal of Vascular Surgery: Venous and Lymphatic Disorders goes further, noting that the modern understanding of the microcirculation emphasises the critical role of the lymphatic system in returning most of the fluid filtered at the smallest vessels to the central venous system.

That is the point of leverage. Venous disease does not just slow the venous route; it increases the amount of fluid that has to leave by the lymphatic one.

How venous pressure wears the lymphatics down

The chain begins with valves. The NHS explains that varicose veins happen when the valves controlling blood flow in a vein do not work properly, so blood builds up and pressure rises. The Cleveland Clinic describes the next stage, chronic venous insufficiency, as damaged leg veins that cannot manage flow, so blood pools and pressure in those veins stays high; without treatment that pressure climbs until the tiniest vessels burst, the skin turns reddish-brown, and the tissue becomes inflamed.

The vascular paper lays out what that does to the lymphatics. In its model, which the authors call congestive lower extremity failure, inflammation leads to chronic venous insufficiency, venous insufficiency produces venous hypertension in the leg, and venous hypertension causes lymphatic system overload. Overload becomes dual system dysfunction: the lymphatic pump fails, lymph flows backward into the skin (dermal backflow), the tissue engorges, and the resulting subcutaneous swelling even impairs the fine arterial supply. The symptoms the paper lists are the ones our clients describe: leg fatigue, heaviness, pain, cramps and progressive swelling.

The Lymphoedema Support Network’s summary is shorter. Swelling occurs when the amount of fluid in an area is greater than the capacity of the lymphatic system to transport it away, and venous insufficiency from varicose veins or deep vein thrombosis is on its list of causes of secondary lymphoedema. The Cleveland Clinic’s lymphedema page says the same in its own words: chronic blood vessel issues may cause lymphedema.

How common is the end result? The vascular paper estimates that phlebolymphedema affects approximately 40 million Americans and calls it under-recognised at primary care clinics, vein centres and wound centres. The National Lymphedema Network lists phlebolymphedema among the position papers it has in preparation, alongside compression, which tells you how recently the condition has been taken seriously as its own entity.

The signs that the lymphatics are now involved

Nobody can see the moment lymphatic transport fails, but the leg changes in recognisable ways. From the Cleveland Clinic, the National Cancer Institute and the Lymphoedema Support Network:

What you notice	What it usually means
Swelling that used to go down overnight now lingers in the morning	The Lymphoedema Support Network describes early lymphoedema as intermittent, minimal on waking and worse through the day; later, without treatment, it becomes permanent
Pressing a thumb in no longer leaves a dent	The NCI notes that early lymphedema pits, and that as it worsens pressing may no longer leave a dent
The skin feels firmer, then thicker	The Cleveland Clinic’s stage II is skin that feels firmer than the surrounding area; stage III adds colour and texture changes
Reddish-brown staining around the ankle	The Cleveland Clinic attributes this to burst capillaries under venous pressure; the vascular paper names the pigment, haemosiderin, and the hardening that follows, lipodermatosclerosis
A calf that feels large and hard	The Cleveland Clinic explains that severe venous swelling can form scar tissue that traps fluid
Repeated skin infections or a sore that will not heal	Both venous ulcers and lymphedema raise the risk of cellulitis; the NHS asks you to see a GP for any leg sore unhealed at two weeks

The Cleveland Clinic grades venous disease from stage 0 (no visible signs, perhaps achy or tired legs) through visible veins, varicose veins, swelling, skin changes, healed ulcer and active ulcer, and only diagnoses chronic venous insufficiency at stage 3 or above. Lymphedema has its own four stages, from stage 0, where flow is impaired but nothing shows, to stage III, with hard, thick skin. A leg can be climbing both ladders at once. Our answer on why lymphedema skin gets thick and hard explains the tissue changes behind the later rungs.

What changes in management

While the problem was venous, the plan was compression, elevation, walking and perhaps a procedure on the vein. Once the lymphatics are involved, the vascular paper argues that both systems have to be treated to restore the tissue, listing compression, interventional procedures for the veins, manual lymphatic drainage, lymphedema pumps and complete decongestive physiotherapy principles as applied by certified lymphedema therapists. Compression stays at the centre; what grows around it is lymphatic care.

In practical terms:

Compression becomes a lymphedema garment, properly fitted. The pressure profile, fabric and fit needed to hold a lymphedematous leg differ from a standard support stocking; the Learning Centre’s compression garments page explains why.
Manual lymphatic drainage joins the routine, moving the trapped protein-rich fluid toward working nodes so the garment has less to hold.
Skin care stops being optional. Thickened, stained skin breaks and infects more easily, and the NCI warns that cellulitis in a lymphedematous limb can become life-threatening if untreated.
Movement is prescribed, not just encouraged. The calf muscle pump drives both venous and lymphatic return.

At Renu this is the territory of complete decongestive therapy, delivered by Meeghan Mackenzie, our Certified Lymphedema Therapist and Certified Compression Fitter. The Learning Centre’s lymphedema and lipedema page describes the programme’s phases, and our answer on lymphatic drainage for varicose vein swelling covers the earlier stage, when the veins are the whole story. None of this replaces your vein specialist: the Cleveland Clinic is clear that valve damage cannot be reversed and that procedures to close or remove diseased veins are how the venous load is reduced, so the two kinds of care run side by side.

When to see a doctor

Long-standing venous swelling deserves a medical review when it changes character, and some changes need prompt attention. Drawing on the NHS and Cleveland Clinic guidance:

swelling that no longer settles overnight, or a leg that has become firm or hard;
new darkening, thickening or weeping of the skin;
a sore on the leg that has not healed after two weeks;
redness, heat, pain or fever in the leg, which can mean cellulitis;
a sudden increase in swelling in one leg, or a vein that has become painful and hard, in case of a clot;
bleeding from a varicose vein.

Call emergency services for leg swelling with breathlessness, chest pain or coughing up blood. The Learning Centre page on when to seek medical care keeps the full list.

Questions people ask

What is phlebolymphedema?

Lymphedema of venous origin. A 2024 paper in the Journal of Vascular Surgery: Venous and Lymphatic Disorders describes it as venous insufficiency causing venous hypertension in the leg, which overloads the lymphatic system until both systems fail together, with dermal lymphatic backflow and progressive swelling. The authors call it under-recognised in primary care, vein clinics and wound clinics alike.

Do all varicose veins lead to chronic venous insufficiency?

No. The Cleveland Clinic reports that varicose veins affect about one in three adults, that each year about one in 50 adults with varicose veins goes on to develop chronic venous insufficiency, and that CVI is only diagnosed at stage 3 or above, when swelling appears. Having varicose veins is a sign of blood flow trouble that can worsen, which is why new ones are worth mentioning to your doctor.

How would I know the swelling has become lymphedema?

Mostly by what the skin and the tissue do. The National Cancer Institute explains that early lymphedema leaves a dent when pressed, but as it progresses pressing no longer leaves a pit; the Cleveland Clinic's lymphedema stages describe skin that feels firmer, then thicker, with colour and texture changes. Swelling that no longer goes down overnight and feels dense rather than soft is the classic shift. A doctor or a lymphedema specialist confirms it.

Does treating the veins reverse the lymphedema?

It can remove part of the load, but not the lymphatic damage. The Cleveland Clinic states that treatment cannot reverse damage to vein valves, and that lymphedema is a chronic condition with effective ways to manage it rather than remove it. The vascular paper argues for treating both sides at once: the veins with compression and procedures, the lymphatics with drainage and decongestive therapy.