Circulation Blocker is a term used to describe a medical condition in which a CLOT forms in a blood vessel, blocking the flow of blood. CLOT is the four letter word that is used to describe this condition. Circulation Blockers can be caused by a variety of factors, including high cholesterol, smoking, and diabetes. If left untreated, circulation blockers can lead to serious health complications, such as stroke or heart attack. Treatment for circulation blockers typically involves medications to dissolve the CLOT and lifestyle changes to reduce the risk of future clots.