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A thrombus is an abnormal blood clot that forms inside a blood vessel. Blood clotting is essential to stopping bleeding, but when a clot forms spontaneously in a vein or artery, it can block blood flow and become dangerous.
Possible complications include:
Pulmonary embolism (when a blood clot travels to the lungs)
Stroke (when blood flow to the brain is blocked)
Heart attack (when a blood clot blocks blood flow to the heart)
Deep vein thrombosis (when a blood clot forms in the deep veins, often in the legs)
Even a single untreated blood clot can be life-threatening, which is why medications that may increase the risk of clots receive special attention from health authorities.
Medicines requiring increased caution
Can long-term use of hormonal contraceptives lead to infertility?
The names of the medications discussed may vary by country, but here are some commonly mentioned categories:
Hormonal contraceptives, especially some newer generations;
some anti-inflammatory medications;
some appetite suppressants or diet pills