Heparin Pharmacology

Heparin Pharmacology

Heparin is an interesting drug with a lot of unique clinical quirks. This drug ultimately inhibits the formation of fibrin. Fibrin is an essential component of a blood clot.

Because heparin has blood thinning effects, it is critical to assess a patient’s bleed risk. Look out for other agents that may increase the risk of bleeding. Examples include; NSAIDs, antiplatelet agents, and other anticoagulants.

One classic test question about heparin that often comes up is the reversal agent. Protamine can be used to help reverse the effects of heparin.

Heparin-induced thrombocytopenia is a critical adverse effect to understand. I discuss both subtypes on the podcast and let you know what to look out for.

Rarer side effects of heparin include hyperkalemia and osteoporosis (only with long term use).

Be sure to check out our free Top 200 study guide – a 31 page PDF that is yours for FREE!

Rivaroxaban Pharmacology

Rivaroxaban is a factor 10a inhibitor that inhibits clot formation and thins the blood.

Rivaroxaban needs to be monitored for bleed risk. Checking periodic CBC can help us assess if hemoglobin and hematocrit are remaining stable.

Enzyme inducers like rifampin, St. John’s Wort, and carbamazepine can reduce concentrations and increase the risk of treatment failure.

NSAIDs and antiplatelet medications can significantly increase the risk of bleed with rivaroxaban.

Rivaroxaban should not be used with dual P-glycoprotein and CYP3A4 inhibitors. Examples include ketoconazole, itraconazole, and ritonavir.

Be sure to check out our free Top 200 study guide – a 31 page PDF that is yours for FREE!