Clopidogrel: uses and side effects

Clopidogrel is an anticoagulant medication, that is, helps prevent blood clot formation and, ultimately, to clog arteries.

Thus, clopidogrel is indicated primarily to prevent blood clots after a patient has suffered a heart attack or a recent cardiovascular accident.. It is also used in people who have a heart problem. or in the blood vessels.

The recommended dose of this medicine is 75 mg once daily.. In addition, treatment should be initiated with a single loading dose of 300 mg in the event that the patient has an acute coronary syndrome, except for people who are over 75 years old with acute myocardial infarction and ST-segment elevation.

How and why clots form?

Blood clots are masses that occur when blood hardens, going from liquid to solid. Depending on where the clot forms, it will be called a thrombus or plunger.

Haemostasis is a process that maintains the integrity of a closed circulatory system and high pressure after vascular damage. There are two types of hemostasis:

  • Primary hemostasis: encompasses all platelet plug formation processes through adhesion, activation, secretion and aggregation of platelets.
  • Secondary hemostasis: involves the activation of the enzymatic coagulation system, which aims to synthesize thrombin and fibrin to stabilize the clot.

Once the clot has formed, the fibrinolysis process takes place. During this process, once the tissue damage has been repaired, different systems work to try to remove the remains of the clot.

When these systems of hemostasis and fibrinolysis are altered it is when the pathological states such as hemorrhages or thrombosis appear, which leads to cardiovascular diseases. On the other hand, there are situations and factors that favor the formation of clots, such as:

  • Obesity.
  • After surgery
  • Genetic factors.
  • Sedentary
  • During and after a pregnancy.
  • People suffering from cancer.
  • Liver or kidney diseases.

As prevention measures, it is essential to have an active life, adopt healthy lifestyle habits and avoid harmful substances for the body, such as tobacco and alcohol.

How does clopidogrel exert its effect on the body?

In order to trigger its anticoagulant effect, Clopidogrel has to be activated in the liver. That is, it must first be metabolized to generate the really active substance. Once the metabolite is formed, it is selectively and irreversibly inhibits platelet aggregation.

It does so by inhibiting the most important complex for fibrinogen: the GIIb / IIIa glycoprotein complex. The inactivation of this factor prevents the binding of fibrinogen to platelets and, ultimately, platelet aggregation.

As the clopidogrel metabolite irreversibly modifies the platelet receptor, Platelets that have been exposed to this medicine will be altered for life. In addition, it also inhibits platelet aggregation induced by other agonists.

Also read: 90% of cardiovascular diseases can be prevented: 5 keys

Clopidogrel adverse effects

This drug, like all those that are marketed, It is not exempt from producing adverse effects. We understand adverse effects like all those unwanted and unintended events that can be expected in treatment with a medication.

In this sense, the overall tolerance of this medicine that has been observed in clinical trials and in studies carried out is good. However, The most characteristic adverse reaction of this type of medication is hemorrhage.

Reported hemorrhages have been observed, mainly, during the first month of treatment. Compared to other medications such as acetylsalicylic acid, Clopidogrel causes less gastrointestinal bleeding and dyspepsia.

But nevertheless, increases the risk of diarrhea and rash. Other adverse reactions that may occur under treatment with this anticoagulant are:

  • Purple.
  • Ecchymosis
  • Hematoma.
  • Epistaxis
  • Neutropenia

In addition, it is important to keep in mind that Concomitant treatment of clopidogrel and acetylsalicylic acid significantly increases the risk to suffer bleeding, compared to monotherapy.

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Clopidogrel is a medicine that It is usually given with acetylsalicylic acid to prevent clot formation in patients who have had a cardiovascular episode.

It is important to control the adverse effects of this medicine, especially if it is given in combination with other anticoagulants, since the hemorrhages that can trigger are serious.

Remember: adopt healthy lifestyle habits It is the best form of prevention of any disease