Signs You Have a "Deadly" Blood Clot Inside You

You may associate blood clotting with the natural process of healing, the scab that develops over a minor scrape or cut. But if a blood clot develops inside you, it can be a dangerous or fatal medical emergency. It can potentially cut off your breathing, cause a stroke, or stop your heart. These are signs you may have a deadly blood clot inside you, according to doctors. Read on to find out more—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.

1. How Do Blood Clots Happen, And Why Are They Dangerous?

"Blood clots can develop in the veins in your legs and block the blood flow in different parts of your body, depending on where the clot travels," says Dr. Sherry Ross, an OB/GYN at Providence Saint John's Health Center in Santa Monica, California. "The clot can travel to your lungs (pulmonary emboli or PE) or your brain causing a stroke. Blood clots are extremely dangerous, even deadly in unusual cases."

2. Signs of a Blood Clot

"Blood clots most commonly develop in the lower leg or thigh," says Dr. Vincent Noori, a board-certified vascular surgeon at Mercy Medical Center in Baltimore. "The most common signs of a blood clot—or a deep vein thrombosis (DVT)—are extremity swelling (most commonly the leg), pain, warmth and erythema [reddening of the skin]. The symptoms often are localized to the calf but can affect the whole leg. They usually occur on one side, but may be felt on both sides, he adds.

Less often, blood clots happen in the arm or lung, says Dr. Jason A. Murray, a Kentucky-based emergency physician. Signs of a blood clot in the arm can include swelling, pain, tingling, or pain upon movement of the elbow or wrist. Signs of a blood clot in the lung can include shortness of breath, particularly on exertion; chest pain; fainting; or a rapid or irregular heartbeat.

3. When Should You Seek Medical Attention?

"You should seek medical attention right away if you suspect a blood clot, especially if it is an abrupt onset of symptoms," says Noori. 

According to Murray, you should especially consider seeking urgent medical attention if you're having symptoms and any of these circumstances apply to you: 

• You've traveled within the last 90 days (such as a long flight or long drive without stopping)
• You've experienced moderate to severe injury (like a painful fall, large bruise, broken bone, or  injury needing a splint or cast)
• You've had recent surgery 
• You're using hormonal birth control or hormone replacement therapy
• You have a recent or actively treated cancer
• You're having chest pain, shortness of breath, fainting, or are coughing up blood

4. What Are Risk Factors for a Blood Clot?

Risk factors for developing a blood clot include:

• Taking hormonal birth control pills. "The hormones in the pill can make your blood thicker than usual causing hyper-coagulation, which is the medical term for causing excessive clotting," says Ross. "The good news is only one in 1,000 women each year will develop a blood clot. Overall the birth control pill is safe, highly effective and the other health benefits outweigh the risks."
• Pregnancy. "The hormonal changes during pregnancy, especially with estrogen, can make the blood thicker than usual causing this hyper-coagulation effect in the blood," says Ross. "Blood clots can happen anytime during pregnancy but are more common in the third trimester or right after delivery."
• Smoking. "Smoking causes many health issues throughout the body, and blood clots are one of those problems," says Ross. "Smoking disrupts the body's ability for the blood to clot normally making it clot more easily. The blood vessels throughout the body are disrupted and damaged by the chemicals in cigarettes making the blood clotting risk higher."
• Surgery. "Certain surgeries involving the hip, lower abdomen and legs increase your risk of blood clots. Surgeries making you less mobile place you more at risk." Wearing support stockings and moving around soon after surgery can help reduce the risk of blood clots.
• Being overweight. "Obesity slows the blood flow in the veins, which increases the risk of blood clots," says Ross.
• Having heart disease. "If the heart is not pumping blood normally throughout the body, the blood flows more slowly and irregularly throughout the body leading to blood clots," says Ross.

5. How Can You Reduce Your Risk of Developing a Blood Clot?

"The best way to prevent DVTs include regular exercise, controlling weight gain and obesity, stopping smoking and avoiding sitting for prolonged periods of time," says Ross. To reduce your risk of blood clots, practice good habits that reduce your risk of heart disease. "Lowering your risk of heart disease starts with eating a healthy plant-based diet, exercising regularly, keeping your BMI under 25, keeping the LDL or 'bad cholesterol' less than 100mg/dl, avoiding high blood pressure and adding omega-3-fatty acids to your diet."

And to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.