What is a common side effect associated with heparin therapy?

Thrombocytopenia is a well-documented side effect of heparin therapy, particularly known as heparin-induced thrombocytopenia (HIT). This condition occurs when there is a decrease in the number of platelets in the blood, which can happen as the body's immune system mistakenly targets the complex formed by heparin and platelet factor 4 (PF4). As a result, patients on heparin can experience a drop in platelet counts, which may lead to an increased risk of bleeding despite the anticoagulant properties of heparin. Monitoring platelet levels is crucial for patients receiving heparin to manage this risk effectively.

While the other listed options can be related to various medications or conditions, they are not typically associated with heparin therapy in the same way thrombocytopenia is. Weight gain is often linked to corticosteroids or certain other medications, hypoglycemia is generally associated with insulin or medications for diabetes, and hypertension can arise from various causes or other drugs, but none are characteristic side effects of heparin administration.