Blood Clots: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Blood Clots?
A hematologist specializes in blood diseases, including clotting and bleeding problems. A hematologist may help when clots return without a clear reason or form in an unusual place. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What it is
A blood clot is a gel-like clump of blood that forms when platelets stick together with proteins to stop bleeding. Clotting is helpful when you have a cut, but a clot inside a vein or artery when it is not needed can block blood flow and damage organs.
Symptoms
Signs depend on where the clot is. A clot in a deep vein, most often in the leg, is called deep vein thrombosis and can cause swelling, warmth, pain, and redness in one leg. A clot that travels to the lungs is called a pulmonary embolism and can cause sudden shortness of breath, chest pain, and coughing up blood. A clot in the brain can cause signs of a stroke: face drooping, arm weakness, or trouble speaking.
Causes and who gets it
Clots can form when blood flow slows down or when a blood vessel is injured. Sitting for long periods, surgery, major injuries, pregnancy, smoking, obesity, and some cancers raise the risk, as do older age and some medicines, such as estrogen-containing birth control pills.
How doctors diagnose it
Doctors start with a physical exam and your health history. An ultrasound is the most common test for leg clots. A D-dimer blood test checks for pieces of clot in the blood. If a lung clot is suspected, doctors may use a CT scan.
Treatment
Most clots are treated with anticoagulants, often called blood thinners. These medicines do not actually thin the blood; they make it harder for new clots to form and keep existing clots from growing. In serious cases, doctors may use a clot-dissolving medicine or a vein filter.
When to see a doctor
See a doctor right away if you have swelling, pain, or warmth in one leg. Call emergency services for sudden shortness of breath, chest pain, coughing up blood, or signs of a stroke.
How a direct primary care or concierge doctor fits in
A direct primary care doctor is paid a flat monthly fee instead of billing insurance; a concierge doctor usually charges more and often works alongside insurance. Both can review your risk factors, order tests, and manage blood thinner follow-up visits. If a clot is serious or keeps coming back, they will refer you to a hematologist.
Common questions
Can a blood clot go away on its own?
Some small clots do break down naturally in the body. Doctors still need to check any suspected clot. Treatment lowers the chance of serious problems.
Can I walk with a blood clot in my leg?
For most people with a diagnosed leg clot, walking is safe and often encouraged. Your doctor will tell you what is right for you, since each case is different.
How long do people take blood thinners?
It depends on why the clot formed and your personal risk. Some people take them for a few months, and others take them for years.
Do long flights really cause clots?
Sitting still for many hours can slow blood flow in the legs, which raises the risk. Moving your legs, drinking water, and walking during breaks can help lower that risk.
Sources
- MedlinePlus - Blood Clots
- Centers for Disease Control and Prevention - About Venous Thromboembolism (Blood Clots) | Venous Thromboembolism (Blood Clots)
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
