Deep vein thrombosis
Deep vein thrombosis is a blood clot in a deep vein, most often in the calf or thigh and less often in the arm.
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Medicines commonly prescribed for Deep vein thrombosis
For informational purposes only. Always consult a doctor before using any medicine.
Dosage form: CAPSULE, 15Active substance: rivaroxabanManufacturer: Adamed Laboratorios S.L.U.Prescription requiredDosage form: CAPSULE, 10 mgActive substance: rivaroxabanManufacturer: Zentiva K.S.Prescription requiredDosage form: TABLET, 2.5 mgActive substance: apixabanManufacturer: Tarbis Farma S.L.Prescription required
Deep vein thrombosis is a blood clot in a deep vein, most often in the calf or thigh and less often in the arm. The danger lies not in the clot itself but in the chance that a piece breaks off and travels through the bloodstream to the lungs. That is why a suspected thrombosis is dealt with the same day: not «let us watch it for a week», but see a doctor today. The good news is that the diagnosis is made quickly, with an ordinary ultrasound scan, and treatment starts straight away and reliably closes off the main risk.
What it looks like
The classic picture involves one leg, not both:
- a bursting or throbbing pain in the calf or thigh, worse on walking and on standing;
- swelling that leaves the leg noticeably thicker than the other one, with a sock pressing a deep groove into it;
- skin warm to the touch over the affected area;
- redness or darkening of the skin — harder to see on brown and black skin, so go by the swelling and the pain;
- surface veins standing out more than usual, firm and tender when touched.
If the clot forms in an arm — which happens after a venous catheter, during cancer treatment and occasionally in young people after heavy exertion — the arm looks the same: swollen, heavy, with the veins over the shoulder standing out.
It is just as important to know the opposite: in roughly half of all cases thrombosis causes almost no symptoms, or passes for a pulled muscle. That is why unexplained swelling of one calf after an operation, a plaster cast, a long flight or a spell of bed rest is treated as thrombosis until proven otherwise.
When to call an ambulance
Call the emergency services at once — the single European number is 112 — if any of the following joins the pain and swelling in the leg:
- sudden shortness of breath, breathlessness at rest;
- chest pain that gets worse on a deep breath or on coughing;
- coughing up blood;
- a racing heart, sudden weakness, vision going dark, fainting.
That is how a pulmonary embolism shows itself: the clot has reached the lungs. It is life-threatening and is treated in hospital only. Note one thing: breathlessness and chest pain call for an ambulance even when the leg is perfectly fine, because the clot may have left the vein entirely and the leg has had time to settle down.
Separately there is a rare but extremely severe form of the thrombosis itself. The leg becomes enormous within hours, the skin turns blue or purple, the pain is unbearable, the foot goes numb and cold. It means the entire venous outflow from the limb is blocked; without urgent help the leg can be lost. Here too it is 112 and hospital, not waiting for a scheduled appointment.
Do not drive yourself to hospital: if you become unwell on the way it is dangerous for you and for everyone around you. Ask someone to take you or call an ambulance. Bring a list of the medicines you take.
Who is at greater risk
A clot forms where three conditions meet: the blood pools, the vein wall is damaged, and the blood itself is prone to clotting. Hence the list.
Permanent circumstances:
- age — the risk rises over the years, most noticeably after sixty;
- excess weight and smoking;
- a previous thrombosis, your own or in close relatives;
- cancer and chemotherapy;
- heart failure, inflammatory bowel disease, severe kidney disease;
- varicose veins;
- taking oestrogen-containing contraceptives or hormone replacement therapy;
- inherited and acquired clotting disorders, which are looked for not in everyone but when there is a reason.
Temporary circumstances able to set off a thrombosis on their own:
- an operation, especially on the hip or knee joint or in the abdomen;
- a hospital stay and the first weeks after discharge;
- a plaster cast, a splint, any immobilisation of the leg;
- bed rest because of serious illness;
- a journey of more than four hours with no chance to get up;
- dehydration;
- pregnancy and the six weeks after giving birth;
- a catheter in a large vein.
Sometimes thrombosis appears with no identifiable cause at all. Doctors call such a case unprovoked and take it more seriously: it recurs more often and occasionally turns out to be the first sign of a tumour not yet found or of an autoimmune clotting disorder. After an episode like that your doctor may therefore suggest further investigation and discuss a longer course of medication.
How the diagnosis is confirmed
First the doctor works out how likely thrombosis is in your particular case, scoring the signs, the circumstances of recent weeks and the state of the other leg. From there the path splits in two. Where the probability is low, a D-dimer blood test is taken: if it is normal, thrombosis is all but ruled out and that is the end of it. Where the probability is high the test is not needed: a compression ultrasound scan of the veins is done straight away, showing whether the vein compresses and whether blood is flowing through it.
The scan should be done within twenty-four hours. If it cannot happen that quickly, the doctor starts treatment in advance — the first dose is given before confirmation, because the risk of waiting outweighs the risk of an unnecessary injection. Sometimes the first scan finds nothing while the suspicion remains: the scan is then repeated a few days later. Where pulmonary embolism is suspected, a computed tomography scan of the lung arteries is done. Contrast venography is rarely used today, only in difficult cases where ultrasound has given no answer.
How it is treated
The mainstay of treatment is medication that lowers the clotting of the blood. It does not dissolve a clot that has already formed: its job is different — to stop it growing and reaching the lungs while the body breaks it down on its own. Tablets from the direct oral anticoagulant group are most commonly prescribed today; they require no regular blood monitoring. The older option is vitamin K antagonists in tablet form, which are cheaper but need regular monitoring of the clotting value and care with food and other medicines. Injections of low molecular weight heparin under the skin are used at the start of treatment, during pregnancy and often in cancer patients.
All of this has to be taken for at least three months. If the thrombosis happened against a clear temporary cause — an operation, a cast — that is usually where it stops. If no cause is found, if the episode is a repeat one, or if a permanent risk factor remains, treatment is extended, sometimes indefinitely, and reviewed once a year. In pregnancy the plan is different: heparin injections throughout the pregnancy and for at least six weeks after the birth, because the tablets are not safe for the baby.
Surgery is rarely needed. Dissolving the clot through a catheter, or removing it mechanically, is considered in extensive thrombosis that threatens the leg. A filter in the inferior vena cava is placed in people for whom anticoagulants are ruled out, for instance because of bleeding.
While you are taking these medicines, some simple safety rules apply. Do not miss doses and do not stop the course on your own: abrupt withdrawal brings the risk straight back. Tell any doctor about the treatment, dentists included, before any procedure. Do not take painkillers from the anti-inflammatory group on your own initiative: together with an anticoagulant they raise the chance of bleeding considerably, so ask what you may take. And see a doctor if you notice black stools, blood in the urine or in vomit, unusually heavy periods or large bruises with no knock; after a blow to the head, without delay, even if you feel well.
After a thrombosis: recovery and what lowers the risk
There is no need to lie down. As soon as the pain allows, walk — movement improves the outflow and does not increase the danger of the clot breaking off, contrary to the old belief. When sitting, keep the leg raised. Swelling and heaviness do not go away at once: some people live for months with that bursting feeling and darkened skin on the calf. That is post-thrombotic syndrome, and for it a compression stocking of the right class is fitted. Long journeys after a recent thrombosis are postponed, but the exact interval is set by your doctor for your case, not by a general recommendation from the internet.
What genuinely lowers the chance of a new episode:
- move every day and keep up your usual activity — a walk works better here than any supplement;
- do not sit still for hours: get up once an hour and, if getting up is impossible, flex and stretch your feet;
- drink enough, especially in hot weather and while travelling;
- lose weight if there is excess and give up smoking;
- on journeys of more than four hours, loose clothing, water rather than alcohol, a walk down the aisle and calf exercises; for people at high risk the doctor may advise compression stockings or an injection before the flight;
- on admission to hospital and before an operation, ask whether your thrombosis risk has been assessed and whether prevention has been prescribed; it often continues after discharge, because a clot can form weeks later.
Women who have had a thrombosis are usually moved to a different method of contraception: oestrogen-containing preparations are not prescribed after such an episode. Planning a pregnancy is also discussed in advance, since prevention will be needed.
Online consultation
A suspected fresh thrombosis is neither confirmed nor excluded online: it needs examination and a scan the same day, and with breathlessness or chest pain, an ambulance. Everything else, though, a remote appointment handles well. The doctor works through how far your symptoms resemble a thrombosis and where to go right now, assesses the risk before a long flight or an operation, explains how to take the prescribed anticoagulant, what to do about a missed dose and which drug combinations are dangerous. Online is also a good place to discuss what drags on after the illness: persisting swelling, the choice of compression, when treatment should end, changing contraception and the question of testing relatives for an inherited tendency to clotting.
This material is for information only and does not replace medical advice.
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Online doctors for Deep vein thrombosis
Discuss your symptoms and possible next steps for Deep vein thrombosis with a doctor online.
