The term antifibrinolytics is used in pharmacology and human medicine to describe various active substances that lead to the dissolution of fibrin. Through this, antifibrinolytics prevent the development of bleeding, which is why they are also called hemorrhage or plasmin inhibitors.
What are antifibrinolytics?
The antifibrinolytic drug class is composed of the active ingredients tranexamic acid and aprotinin. While the latter is a plasmin inhibitor, the former is considered an amino acid. Both have in common that they lead to an inhibition of bleeding. Antifibrinolytics are therefore also considered plasmin inhibitors or bleeding stoppers. They cause an inhibition of fibrin, resulting in increased blood clotting. The best-known antifibrinolytics include the preparations Cyklokapron and Trasylol. Antifibrinolytics are typically taken orally. Intravenous administration is also possible. They are subject to pharmacy and prescription requirements, so they are only available from a licensed pharmacy based on a physician’s prior prescription.
Pharmacological effects on the body and organs
The mechanism of action of all antifibrinolytics is based on an effect on the body’s own fibrin. This is the activated cross-linked protein responsible for plasmatic coagulation of human blood. Antifibrinolytics cause an inhibition of plasmin after ingestion. This is the substance responsible for the dissolution of fibrin. As a result of the reduced dissolution of fibrin, the level of the protein in the blood increases. This reduces blood loss. Antifibrinolytics thus succeed in suppressing fibrinolysis by pharmacological means.
Medical application and use for treatment and prevention.
Antifibrinolytics can be used for therapeutic purposes as well as preventively as part of prophylaxis. The purpose of administration is always to treat bleeding that occurs as a result of hyperfibrinolysis. Hyperfibrinolysis occurs when the enzymatic cleavage of the endogenous protein fibrin (fibrinolysis) is pathogenically increased. Some antifibrinolytics, such as tranexamic acid, are also suitable for use as antidotes. Antidotes are substances that inactivate the effects of a toxic substance or at least reduce or attenuate its effects. However, the field of application as an antidote remains limited to the treatment of bleeding that occurs during fibrinolytic therapy. Antifibrinolytics are also used in obstetrics. Here they are intended to improve coagulation in postpartum hemorrhage. In addition, there is also an indication in dental procedures and surgical procedures with an increased risk of bleeding (e.g., operations of the prostate or gastrointestinal tract). In these cases, antifibrinolytics are administered as prophylactic agents. Other areas of application for antifibrinolytics include persistent nosebleeds, hereditary angioneurotic edema, fibrinogen administration, and particularly pronounced menstrual bleeding (hypermenorrhea). Antifibrinolytics can be administered intravenously or taken orally (as effervescent or film-coated tablets). All representatives of this class of agents are subject to pharmacy and prescription requirements.
Risks and side effects
Antifibrinolytics, like other medically active substances, can lead to undesirable side effects after ingestion. First, check whether there is a known allergy to antifibrinolytics. If this is the case, it is imperative to refrain from taking them, as there is a contraindication. This describes the presence of a medical contraindication that prohibits treatment from a medical point of view. There is also a contraindication during breastfeeding, as antifibrinolytics can pass into breast milk. Patients suffering from thrombosis or at increased risk of thrombosis must also not take antifibrinolytics. During pregnancy, a comprehensive risk assessment must be performed by the physician. Common side effects include skin reactions (itching, rashes, redness), atrial fibrillation, and visual disturbances. For patients at risk of thrombosis, there is also a risk of stroke, myocardial infarction, or pulmonary embolism. In addition, when antifibrinolytics are used to treat urinary bleeding, coagulums may form, leading to further hazards.Therefore, a comprehensive risk-reward assessment must be performed in advance of use, as a contraindication may exist.
