Validol

Chemical structure and composition

From a chemical standpoint, validol (Validolum) is not just a single molecule, but a specific liquid mixture. Its chemical structure is based on dissolving one active component in another. Mentyl isovalerate acts as the solvent. Pure menthol is integrated into this base.

The concentration of menthol in the final solution is strictly standardized and always ranges from 25 to 30 percent. It is this proportion that ensures the optimal physicochemical interaction of the drug with the mucosal structures upon application. Menthol within the mentyl isovalerate base retains its ability to actively affect the body's sensory systems, which determines the entire subsequent pharmacodynamics of the medicinal product.

Mechanism of reflex action

The key feature of the drug lies in its reflex mechanism of action. This means that the mechanism is realized through a complex neurophysiological chain rather than by direct action on blood vessels:

1. Primary reception: When the drug is placed in the oral cavity, especially in the sublingual region, it begins to actively irritate specific cold receptors embedded in the mucosa.
2. Afferent transmission: The excitation of these receptors generates a nerve impulse that travels to the central nervous system (CNS).
3. Efferent response: The CNS processes the incoming signal from the cold receptors and triggers a corresponding autonomic response.
4. Final effect: The result of this reflex is reflex dilation of the coronary arteries (the blood vessels supplying the myocardium).

Thus, the therapeutic effect depends entirely on how effectively the irritation of receptors in the mouth can trigger the reflex arc through the CNS.

Therapeutic efficacy and indications

Despite the clearly described reflex mechanism, the clinical value of the drug has strict limitations. The potency of this agent is characterized as weak and inconstant. The central nervous system's reflex response to cold receptor irritation is individual and does not always lead to sufficient dilation of the coronary arteries.

Indications for use are strictly limited:

• The drug is advisable to use only for relieving mild and initial forms of angina attacks.
• It may be effective at the very early stages of an anginal attack.

Important limitation: The drug is completely unsuitable for relieving severe attacks of angina. In case of pronounced pain syndrome, a weak reflex effect will be insufficient to restore adequate blood supply to the heart muscle.

Administration route and dosage forms

For the reflex mechanism to work, the drug must come into contact with the zone of maximum concentration of cold receptors. That is why the only correct administration route is sublingually (under the tongue). The drug must be kept in the sublingual region.

The pharmaceutical industry offers several dosage forms convenient for sublingual administration:

• Solution (drops) — a liquid form placed under the tongue.
• Capsules — shells containing the active solution inside.
• Sublingual tablets — a solid form intended for resorption in the oral cavity.

Note: Forms such as aerosols or injection solutions do not exist for this drug and are not used, as they exclude the necessary contact with the oral mucosa.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Neurophysiology of the reflex arc: from cold receptors to coronary arteries.
• The role of the central nervous system in regulating coronary vascular tone.
• Comparative characteristics of dosage forms for sublingual administration (drops, capsules, tablets).
• Criteria for the differential diagnosis of mild and severe angina attacks to select the drug.

Other topics in the section "Cardiovascular Drugs"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.