Blood clots: spot them early, prevent them, and act fast

A blood clot can be quiet and still dangerous. Some clots start in a leg and travel to the lungs without much warning. Knowing the signs and simple prevention steps can make the difference between a quick fix and an emergency.

Put plainly, a blood clot is a clump of blood that becomes solid inside a vessel. Clots help stop bleeding after an injury, but when they form inside veins or arteries without a good reason, they can block blood flow. Two types you’ll hear about are deep vein thrombosis (DVT), usually in the leg, and pulmonary embolism (PE), when a clot reaches the lung.

Signs to watch for — when to call a doctor now

DVT often causes swelling, pain, warmth, or redness in one leg. It can feel like a cramp that won’t go away. PE is more serious and can cause sudden shortness of breath, sharp chest pain (worse when you breathe in), racing heart, lightheadedness, or coughing up blood. If you have any of those PE signs, get emergency help immediately.

Not every clot fits a clear checklist. Some people have mild symptoms or none at all. If you’re at higher risk (see next section) and notice anything odd, call your provider—don’t wait until it’s severe.

What raises your risk and how to lower it

Common risk factors include recent surgery or hospital stay, long periods of immobility (think long flights or bed rest), cancer, pregnancy, birth control pills or hormone therapy, smoking, obesity, and a family history of clotting problems. Age and some chronic illnesses add risk too.

Simple prevention works for most people: stay active, break up long sitting periods, drink enough water, and avoid smoking. On long flights, stand up or walk every couple of hours and do ankle circles while seated. After major surgery or if you’re bedridden, doctors may recommend blood thinners, compression stockings, or physical therapy to reduce risk.

Treatment depends on where the clot is and how big it is. Doctors commonly use anticoagulant medicines (blood thinners) to stop a clot from growing and lower the chance of new clots. In severe cases, procedures like clot-busting drugs or surgical removal may be needed. Don’t stop or start blood thinners without medical advice—doing so can be dangerous.

If you want to read deeper on related topics, check out our articles about blood pressure and medication choices (like "Loop vs. Thiazide Diuretics" and "Understanding Azilsartan Medoxomil") and lifestyle factors such as "Understanding the Impact of Obesity on Bladder Health." Those pieces can help you see how overall health affects clot risk.

Got symptoms or a concern? Talk to your doctor. Quick action can prevent a small problem from becoming life-threatening.