Biochemical mechanism of action
The drug belongs to the group of oxidizing agents, whose action is based on the release of oxygen. When the 3% solution comes into contact with damaged tissues, mucous membranes, or wound surfaces, it interacts with the enzyme catalase, which is present in body cells.
Under the action of catalase, a rapid chemical decomposition reaction of hydrogen peroxide occurs: $$H_2O_2 \rightarrow 2H^+ + O_2$$
The key feature of this process is that the reaction releases molecular oxygen ($O_2$). This fundamentally distinguishes hydrogen peroxide from other oxidizing agents (e.g., potassium permanganate), which release more aggressive atomic oxygen.
Pharmacodynamics and effects
The release of molecular oxygen determines three main pharmacological effects of the drug, which have varying degrees of clinical significance:
- Mechanical cleansing (primary effect). Gas release occurs violently, forming abundant foam. This foam physically (mechanically) washes purulent exudate, necrotic tissues, blood clots, and small foreign bodies out of the wound cavity.
- Hemostatic effect. The drug promotes local hemostasis. This is due to the ability of hydrogen peroxide to accelerate the clotting processes of fibrinogen in the wound.
- Bactericidal effect. This is negligible. Since the reaction releases molecular rather than atomic oxygen, the oxidizing capacity of the drug is insufficient for reliable destruction of pathogenic microorganisms. The drug cleanses the wound but does not sterilize it.
Clinical application
In medical practice, a 3% hydrogen peroxide solution is used. The drug is prescribed exclusively externally and topically in the following areas:
- Surgery and traumatology: The drug is the agent of choice for the initial treatment of contaminated wounds, as well as wounds complicated by a purulent process (due to the mechanical flushing effect). It is also used to stop bleeding from superficial wounds and to arrest capillary bleeding.
- Otorhinolaryngology (ENT) and dentistry: The solution is used to stop epistaxis (usually by inserting moistened turundas). Used as mouthwashes and gargles, the drug is prescribed for inflammatory lesions of the oral mucosa and pharynx — such as stomatitis and tonsillitis.
Prescription details
When using the drug, the physician must take into account its pharmacodynamic limitations. Due to its weak bactericidal effect, Solutio Hydrogenii peroxidii diluta cannot serve as the sole agent for the prevention of wound infection. Its main task is to prepare the wound surface (clean it of substrate) and ensure primary hemostasis before applying a bandage or using more potent antiseptics (e.g., halogen-containing compounds).
Briefly: answers to topical questions
What is the difference between the mechanism of action of hydrogen peroxide and potassium permanganate?
The mechanism of action of these agents differs in the type of oxygen released and their interaction with tissues.
| Characteristic | Hydrogen peroxide | Potassium permanganate |
|---|---|---|
| Active factor | Molecular oxygen ($O_2$) formed during decomposition under the action of catalase | Atomic oxygen ($3O$) cleaved upon contact with water |
| Tissue effect | Mechanical cleansing with foam; local hemostatic effect | Formation of albuminates upon binding of manganese oxide with tissue proteins |
| Antimicrobial effect | Negligible | Pronounced antimicrobial effect |
What concentrations of hydrogen peroxide solutions are used in medicine besides 3%?
In addition to the 3% solution, sources indicate the following concentrations of hydrogen peroxide:
- 2.5% solution — used with a detergent for pre-sterilization preparation of non-infected instruments.
- 6% solution — used with a 0.5% detergent for soaking and washing instruments after surgeries involving anaerobic infection.
In addition, 2 tablets of urea peroxide per 100 ml of water yield a 1% solution of the complex preparation used for wound irrigation.
Effect formula: «Catalase → Foam → Clean wound without blood». Peroxide does not kill bacteria (weak molecular $O_2$ is released), but washes them out.
Class and exam questions
Why does hydrogen peroxide have a weak bactericidal effect?
During the decomposition of the drug under the action of catalase, molecular oxygen ($O_2$) is released rather than atomic. Its oxidizing capacity is insufficient to destroy bacterial cell structures.
How does the drug stop bleeding?
The local hemostatic effect is due to the fact that hydrogen peroxide accelerates the clotting of fibrinogen upon contact with damaged tissues.
Which enzyme ensures the decomposition of the drug in the wound?
The decomposition reaction with a violent release of gas bubbles is triggered by the tissue enzyme catalase.
What else to study on this topic
- Comparative characteristics of oxidizing antiseptics (hydrogen peroxide vs. potassium permanganate).
- Differences in the mechanisms of action of molecular and atomic oxygen.
- Halogen-containing antiseptics (iodine preparations) and their denaturing effect on proteins.
- The biochemical blood coagulation cascade and the role of fibrinogen in hemostasis.
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