Seven-time NBA all-star Damian Lillard, 34, recently joined a growing list of NBA athletes to be sidelined by a diagnosis of deep-vein thrombosis, or DVT.

The Milwaukee Bucks player joins Victor Wembanyama, 21, a rising star in the NBA who was diagnosed with the life-threatening condition earlier this season, along with Chris Bosh and Brandon Ingram, who were also sidelined with DVT during their careers.

DVT is caused by blood clots in the veins of the arms or legs. The condition is commonly associated with age, decreased mobility, obesity, some estrogen-containing medications and smoking, among other factors. Repetitive arm action above the head, like throwing a basketball, can also increase the risk of DVT.

Typically, DVT causes swelling, pain and bruising in the affected limb. DVT on its own is not lethal, but left untreated, it can have serious consequences.

Without treatment, pieces of blood clots that cause DVT can break off and travel to the lungs in a condition called pulmonary embolism (PE), which can result in severe damage to the lungs. Both DVT and PE are venous thromboembolic diseases, which are the third most common cause of deaths associated with the vascular system after heart attack and stroke.

Tennis superstar Serena Williams developed PE twice. Like many people who develop it, she had trouble breathing, shortness of breath and chest pain.

Although it might be scary to be diagnosed with DVT or PE, there are effective medicines to treat the conditions.

My lab's research focuses on identifying new blood-thinning drugs to treat blood-clotting conditions like DVT and stroke. Surgery and blood thinners are often combined to combat DVT and PE by removing the original blood clot and reducing the chances of a new clot forming.

Despite their name, blood thinners do not literally make blood thinner. Instead, they make it harder for blood clots to form. Three general classes of blood thinners can be prescribed for DVT and PE: vitamin K antagonists such as warfarin, heparin and direct oral anticoagulants.

Despite the help blood thinners provide, they create risks of their own, as they can increase the risk of bleeding, because blood clotting is a normal and necessary physiological process.

Taking blood thinners is like walking a tightrope. The person taking the blood thinner is in a constant state of balance between preventing abnormal blood clots and excessive bleeding, which depends on the strength of the blood thinner. If you lean too far in either direction, you might fall off the tightrope, with serious consequences.

The challenges of managing bleeding risk while preventing DVT was amplified in the case of Williams. Immediately after delivering her second child, Williams underwent a PE event and was placed on intravenous heparin. While heparin did prevent blood clots, Williams did have significant bleeding at the site of her C-section.

The risk of bleeding often extends past the hospital. Typically, blood thinners are given to people with DVT for months, even years, to prevent ongoing risk of clot formation. The risk of bleeding persists as long as the person is taking the drug.

Athletes on blood thinners playing contact sports are more vulnerable to injuries compared to others. Players commonly fall, which is more likely to cause potentially life-threatening internal bleeding.

Due to this risk, athletes often must take to the sidelines to avoid injury after a DVT diagnosis.

The challenge of creating balanced blood-thinning drugs is of great interest to my lab at McMaster University's Thrombosis and Atherosclerosis Research Institute. A promising candidate for treating clotting disorders is ADAMTS13. It's a protein that plays a role in the typical maintenance of blood clots but shows great potential as a blood-thinning medication.

Previous research with this protein has found that in acute blood-clotting conditions such as ischemic stroke, ADAMTS13 is effective at breaking apart blood clots but does not result in the same risk of bleeding. Further testing on the protein in chronic conditions like DVT still needs to be performed, but there is potential for it to act as a long-term blood thinner.

The use of safer blood thinners will not only allow athletes like Lillard and Wembanyama to continue playing their respective sports, but will also help the general population.

Approximately seven million new blood-thinner prescriptions for DVT and other conditions are written each year in Canada, highlighting the need for better therapeutics across the board.