How Do Glycoprotein IIb/IIIa Inhibitors Work?

Glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitors are a class of drugs that work by preventing the formation of blood clots by inhibiting the action of platelets. Because of their actions on the platelets, GP IIb/IIIa inhibitors are also called antiplatelet therapies and are prescribed in cases of serious heart conditions. Platelets are small cell-like components in the blood whose primary function is to close the wound or injury and prevent blood loss. However, when unintended blot clots are formed within the body, they may lead to heart attack and stroke. Clots can also form if you have had a major surgery such as heart surgery or hip replacement surgery.

The surface of platelets is covered with GP IIb/IIIa receptors that help them clump together, causing platelet aggregation. In case of an injury or bleeding, key clotting components called fibrinogen and von Willebrand factor bind with the receptors and form a blood clot by platelet aggregation.

GP IIb/IIIa inhibitors block GP IIb/IIIa receptors and stop the formation of blood clots. As the receptors are blocked, fibrinogen and von Willebrand factor cannot bind with the plasma membrane and blood clots are not formed.

GP IIb/IIIa inhibitors are used for the management of acute coronary syndrome such as:

• Unstable angina (chest discomfort caused by poor blood supply to the heart muscle)
• Non-ST elevation myocardial infarction (heart attack) that requires percutaneous coronary interventions within 24 hours
• GP IIb/IIIa inhibitors are known to reduce death or nonfatal myocardial infarction

The primary side effect of GP IIb/IIIa inhibitors is bleeding. The risk of bleeding complications has limited the use of GP IIb/IIIa inhibitors, which are now reserved for high thrombotic risk settings.

The other common side effects may include:

• Cardiovascular side effects such as low blood pressure and a decrease in heart rate
• Decrease in platelet count (acute thrombocytopenia) which may cause severe bleeding
• Hypersensitivity reaction and local injection site complications are rare but may be present
• Renal function impairment may be seen with some drugs

The information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

Drug names of GP IIb/IIIa Inhibitors include:

• Abciximab
• Aggrastat
• Eptifibatide
• Integrilin
• ReoPro
• Tirofiban