Stages of varicose veins: the CEAP classification in plain words

2026-10-12

• CEAP is the international language of vein specialists, updated in 2020; it describes vein disease rather than passing a verdict.
• Clinical classes run from C0 to C6, from no visible signs to an open venous ulcer.
• The letters E, A and P add the cause, the veins involved and the mechanism: backward flow or blocked outflow.
• Vein disease does not have to pass through every stage, and you can help your legs at any of them.
• Bleeding from a vein, or sudden swelling and pain in one leg, means calling 103 straight away.

After a vein ultrasound, many people are handed a report with a puzzling line such as C2S, Ep, As, Pr, and leave the room wondering: is that a lot or a little? How serious is it? You felt awkward asking the doctor to explain, and the internet offers dozens of contradictory answers.

Let's go through it calmly. Behind those letters is CEAP, an international classification used by vein specialists all over the world. It describes the stages of varicose veins and other chronic venous diseases in a shared language that doctors understand and that is perfectly accessible to patients too.

What is the CEAP classification and why is it used?

CEAP was created in the 1990s, and in 2020 an international panel of experts updated it. Thanks to it, a phlebologist in Tashkent, Samarkand or abroad will understand what is happening in your legs in the same way, and the results of treatment can be compared with where you started.

The name is made up of the first letters of four words:

• C (Clinical): the clinical signs, meaning what the doctor can see and feel during the examination;
• E (Etiology): the cause of the disease;
• A (Anatomy): which veins are affected;
• P (Pathophysiology): what exactly has gone wrong in the way the veins work.

Patients most often come across the first letter, the clinical class. This is what people usually call the stage of varicose veins, although strictly speaking these are classes, and nobody is bound to move from one to the next.

Clinical classes C0 to C6: what the doctor sees

The clinical part is the heart of the classification. The doctor examines your legs while you stand and records every sign you have:

• C0: no visible or palpable signs of vein disease, although you may still have complaints such as heaviness.
• C1: telangiectasias, the spider veins less than 1 mm across, or reticular veins, bluish vessels from 1 to 3 mm across.
• C2: varicose veins, meaning widened veins under the skin that are 3 mm or more across when measured standing.
• C3: swelling caused by vein disease.
• C4: changes in the skin and the tissue beneath it caused by venous insufficiency.
• C5: a healed venous ulcer.
• C6: an open, active venous ulcer.

We have written in more detail about the mildest class in our article on spider veins on the legs. Remember that legs can swell not only because of the veins but also with heart, kidney or thyroid disease, or as a side effect of some medicines. That is why class C3 is assigned by a doctor after tests; you can read about the possible causes in our article on evening leg swelling.

What is new in CEAP 2020?

The updated version added some details that help describe the legs more precisely:

• C2r: recurrent varicose veins, meaning veins that have come back after treatment;
• C4a: pigmentation (darkening of the skin) or venous eczema;
• C4b: lipodermatosclerosis (hardening of the skin and underlying tissue) or atrophie blanche, pale patches of thin skin;
• C4c: corona phlebectatica, a fan of tiny dilated veins around the ankle and foot;
• C6r: a venous ulcer that has opened again.

In addition, the letter S is added to the clinical class if you have symptoms such as pain, heaviness, a bursting feeling, cramps or itching, and the letter A if you have none. For example, C2S means varicose veins that bother you, while C1A means spider veins that cause no discomfort at all.

What do the letters E, A and P mean in your report?

These parts of the classification matter most to specialists, but it helps patients to know what they mean too.

E for cause

• Ep: primary vein disease, where the vein walls and valves have weakened without any obvious outside cause. This is the most common type.
• Es: secondary disease, for example after a deep vein thrombosis or an injury.
• Ec: congenital abnormalities of the veins; En: no cause could be identified.

A for anatomy

• As means the superficial veins are affected, Ad the deep veins, and Ap the perforator veins that connect the superficial and deep systems; An means no changes were found.

P for mechanism

• Pr means reflux, where the valves fail and blood flows backwards, down the leg; Po means obstruction, something blocking the outflow of blood; Pr,o means both; Pn means no abnormality was found.

The doctor clarifies these details with duplex ultrasound. So the line C2S, Ep, As, Pr from the beginning of this article reads quite plainly: varicose veins with symptoms, primary disease, superficial veins affected, caused by valves that don't close properly. This is a common and well-studied situation.

Does vein disease always move from one stage to the next?

No. The stages of varicose veins in CEAP describe what is there now; they are not a timetable for the future. In some people spider veins stay as spider veins for many years, while in others the disease progresses over time. It depends on heredity, weight, lifestyle, the kind of work you do and other factors, and nobody can predict the course for a particular person in advance.

The good news is that you can help your legs at any stage. Regular movement, keeping your weight under control, resting with your legs raised and, if your doctor recommends it, compression stockings all reduce symptoms and the load on your veins. If the changes are more marked, a phlebologist will discuss modern treatment options with you.

How can you tell which class your legs belong to?

On your own you can only make a rough guess. The class is set by a phlebologist, who examines your legs, asks about your symptoms, family history and any previous thrombosis, and refers you for a vein ultrasound. Sometimes what seems like simple tiredness turns out to be reflux in a large vein, while noticeable blue vessels turn out to be harmless reticular veins.

Book an appointment if you notice:

• heaviness, a bursting feeling or aching in your legs by evening; we have written separately about heavy legs;
• bulging, twisting veins, especially after standing for a long time;
• ankle swelling that goes down overnight and comes back by evening;
• darkening, itching, flaking or hardening of the skin on your lower legs.

The main points

The CEAP classification is not a verdict but a common language in which doctors and patients can talk about vein health. Once you know what the stages of varicose veins from C0 to C6 and the letters E, A and P mean, you will understand your report better and be able to ask your doctor precise questions. And whatever class appears on paper, movement and care for your legs are always worthwhile.

Sources: 1. Lurie F, Passman M, Meisner M, et al. The 2020 update of the CEAP classification system and reporting standards. J Vasc Surg Venous Lymphat Disord. 2020;8(3):342–352. 2. De Maeseneer MG, Kakkos SK, Aherne T, et al. ESVS 2022 Clinical Practice Guidelines on the Management of Chronic Venous Disease of the Lower Limbs. Eur J Vasc Endovasc Surg. 2022;63(2):184–267.

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