Mechanism of Action
Aminocaproic acid (Acidum aminocapronicum) has a unique dual mechanism aimed at inhibiting fibrinolysis and preserving the blood clot (thrombus).
- Blockade of Activation: The drug binds to plasminogen. This interaction reliably blocks plasminogen activation and prevents its conversion into the active enzyme — plasmin.
- Direct Inhibition: The agent exerts a direct inhibitory effect on already formed plasmin. It prevents plasmin from interacting with fibrin, protecting the fibrin clot from enzymatic degradation (lysis).
Thus, the thrombus maintains its structural integrity, which is critical for arresting hemorrhage. Its structural analogue, aminomethylbenzoic acid (Amben), shares a similar mechanism of action.
Indications for Use
The primary indication for the drug is the management of bleeding caused by excessive, pathological activity of the fibrinolytic system. In clinical practice, this condition occurs in the following scenarios:
- Surgery and Traumatology: Major trauma, surgical procedures involving tissues rich in plasminogen activators.
- Obstetrics and Gynecology: Pathological labor complicated by coagulopathy, as well as menorrhagia.
- Urology: Bleeding associated with prostatitis.
- Gastroenterology: Severe liver disease. Liver failure impairs the synthesis of both coagulation factors and natural inhibitors of fibrinolysis, requiring pharmacological correction.
- Toxicology and Intensive Care: Specific therapy for the overdose of fibrinolytic agents (thrombolytics).
Adverse Effects
The use of aminocaproic acid may be accompanied by several adverse reactions requiring medical monitoring:
- Cardiovascular System: Hypotension, bradycardia, and various arrhythmias may develop. The risk of cardiovascular complications increases if the intravenous infusion rate is not properly controlled.
- Gastrointestinal Tract: Dyspeptic symptoms, including nausea and diarrhea.
- Central Nervous System: Patients may report dizziness.
Note: In contemporary practice, other synthetic analogues, such as tranexamic acid (Tranexamic acid), surpass aminocaproic acid in clinical efficacy and have a longer duration of action.
Formulations and Administration
The drug is available in two main formulations, allowing for both systemic and local use:
- Powder for oral administration.
- Solution in vials (5% — 100 mL) for intravenous administration.
Dosing Regimens:
- Oral (per os): 2.0–3.0 g.
- Parenteral: Administered via slow intravenous drip. The recommended infusion rate is 50–60 drops per minute, which minimizes the risk of cardiovascular adverse effects (hypotension and arrhythmias).