Linked from
The 14 pages that link to Anticoagulant, each with the reason it gives.
ThrombosisRelated: Anticoagulants are used to prevent thrombus extension and new clot formation.
EctoparasiteRelated: Blood-feeding ectoparasites can use anticoagulants to keep a meal flowing.
HematophagyRelated: Many blood feeders release anticoagulants to keep blood flowing during feeding.
NosebleedRelated: These medicines can prolong bleeding and affect treatment decisions.