They usually develop in the legs or arms, but they can form almost anywhere in the bay, including around the heart, brain or lungs.
Left untreated, the clot may make its way into the lungs, which can be very serious. This is known as a pulmonary embolism.
It’s, therefore, absolutely essential that you seek medical attention if you think that you have a blood clot.
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It said: “Deep vein thrombosis occurs when a blood clot forms in one of the deep veins of your body, usually in your legs, but sometimes in your arm.
“Symptoms of a blood clot may feel similar to a pulled muscle or a ‘Charley horse’.
“But they may differ in that the leg (or arm) may be swollen, slightly discoloured, and warm.
If you have a blood clot that makes it all the way into the lungs, it’s known as a pulmonary embolism.
A pulmonary embolism can be deadly, and you should dial 999 and ask for an ambulance if you’re worried that you might be at risk.
The most common sign of a pulmonary embolism is having sudden shortness of breath.