Blood Clots
Learn about Blood Clots, its reported features, relevant specialists, and questions to discuss at a medical consultation.
Also known as: Hypercoagulability; Thrombophlebitis; Venous Thrombosis
The sources compiled here do not cover: prognosis, onset, prevalence. Ask the treating doctor about these.
What is a blood clot?
From: MedlinePlus, National Library of Medicine
A blood clot is a mass of blood that forms when platelets, proteins, and cells in the blood stick together. When you get hurt, your body forms a blood clot to stop the bleeding. After the bleeding stops and healing takes place, your body usually breaks down and removes the blood clot. But sometimes the blood clots form where they shouldn't, your body makes too many blood clots or abnormal blood clots, or the blood clots don't break down like they should. These blood clots can be dangerous and may cause other health problems.
Blood clots can form in, or travel to, the blood vessels in the limbs, lungs, brain, heart, and kidneys. The types of problems blood clots can cause will depend on where they are:
- Deep vein thrombosis (DVT) is a blood clot in a deep vein, usually in the lower leg, thigh, or pelvis. It can block a vein and cause damage to your leg.
- A pulmonary embolism (PE) can happen when a DVT breaks off and travels through the bloodstream to the lungs. A PE, especially if it is large, can damage your lungs and prevent your other organs from getting enough oxygen.
- Cerebral venous sinus thrombosis (CVST) is a rare blood clot in the venous sinuses in your brain. Normally the venous sinuses drain blood from your brain. CVST blocks the blood from draining and can cause a hemorrhagic stroke.
- Blood clots in other parts of the body can cause problems such as an ischemic stroke, a heart attack, kidney problems, kidney failure, and pregnancy-related problems.
Who is more likely to develop blood clots?
From: MedlinePlus, National Library of Medicine
Certain factors can raise your risk of developing blood clots:
- Atherosclerosis
- Atrial fibrillation
- Being overweight or having obesity
- Cancer and cancer treatments
- Certain genetic disorders
- Certain surgeries
- COVID-19
- Diabetes
- Family history of blood clots
- Overweight and obesity
- Pregnancy and giving birth
- Serious injuries
- Some medicines, including birth control pills
- Smoking
- Staying in one position for a long time, such as being in the hospital or taking a long car or plane ride
What are the symptoms of blood clots?
From: MedlinePlus, National Library of Medicine
The symptoms for blood clots can be different, depending on where the blood clot is:
- In the abdomen: Abdominal pain, nausea and vomiting
- In an arm or leg: Sudden or gradual pain, swelling, tenderness, and warmth
- In the lungs: Shortness of breath, pain with deep breathing, rapid breathing, and increased heart rate
- In the brain: Trouble speaking, vision problems, seizures, weakness on one side of the body, and sudden severe headache
- In the heart: Chest pain, sweating, shortness of breath, and pain in the left arm
How are blood clots diagnosed?
From: MedlinePlus, National Library of Medicine
To find out if you have one or more blood clots, your health care provider:
- Will do a physical exam.
- Will take your medical history, which includes asking about your symptoms.
- May order blood tests, including a D-dimer test.
- May order imaging tests, such as Ultrasound. X-rays of the veins (venography) or blood vessels (angiography) that are taken after you get an injection of special dye. The dye shows up on the x-ray and allows the provider to see how the blood flows. CT Scan.
What are the treatments for blood clots?
From: MedlinePlus, National Library of Medicine
Treatments for blood clots depend on where the blood clot is located and how severe it is. Treatments may include:
- Blood thinners.
- Other medicines, including thrombolytics. Thrombolytics are medicines that dissolve blood clots. They are usually used where the blood clots are severe.
- Surgery and other procedures to remove the blood clots
Can blood clots be prevented?
From: MedlinePlus, National Library of Medicine
You may be able to help prevent blood clots by:
- Moving around as soon as possible after having been confined to your bed, such as after surgery, illness, or injury
- Getting up and moving around every few hours when you have to sit for long periods of time, for example if you are on a long flight or car trip
- Wearing compression stockings after surgery or during a long flight
- Regular physical activity
- Not smoking
- Staying at a healthy weight
Some people at high risk may need to take blood thinners to prevent blood clots.
Which doctor should you see?
The suggested department for discussing Blood Clots is Haematology, with a haematologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.
This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.
How to prepare for an assessment
Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.
Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.
- Which blood-cell, marrow, bleeding or clotting finding matters most?
- Does the diagnosis need confirmation or a more precise subtype?
- Which symptoms or laboratory changes should trigger earlier review?
Treatment discussions and follow-up
Where the source describes treatments, these are an overview of possible care, not a prescription for an individual. Ask which option applies to the confirmed diagnosis, what benefit is expected, what adverse effects to watch for and how progress will be assessed. Availability, approvals and local practice can differ from the country described in the source.
Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.
The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.
When to seek emergency help
Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.
This condition is usually assessed by a haematologist. Every profile shows the doctor’s registration and what has been checked.
Sources
- MedlinePlus, National Library of Medicine — Blood Clots — Public-domain health-topic summary
- Government of India — Emergency Response Support System — Official reference for India emergency number
Source: MedlinePlus, National Library of Medicine. Orphadata Science: Free access data from Orphanet. © INSERM 1999; July 2026 data, CC BY 4.0. This product uses the Human Phenotype Ontology (hp/releases/2026-09-01). Only sources listed for this article apply. Source material has been selected and arranged; HPO definitions are reproduced without alteration. No source organisation endorses this compilation. Köhler S et al. The Human Phenotype Ontology project: linking molecular biology and disease through phenotype data. Nucleic Acids Research 2014;42(D1):D966–D974. doi:10.1093/nar/gkt1026.
General information, not advice about your situation. Errors can be reported through the corrections process. Reference TDI-C-0368.