Benzydamine

Benzydamine at high doses occupies a peculiar niche among deliriants -- it produces the characteristic hallucinations and confusion of anticholinergic delirium but overlays them with a stimulating, almost manic energy that sets it apart from the heavy sedation of tropane alkaloids. The onset takes one to two hours, beginning with a restlessness that builds in the limbs, an electrical agitation that makes sitting still feel increasingly intolerable. The mouth dries. The heart quickens. There is a building sense of urgency, a feeling that something is about to happen, though what that something might be remains frustratingly undefined.

As the dose takes hold, the stimulation intensifies into something approaching genuine mania. Thoughts race, tumbling over one another in a torrent that resists organization. Speech becomes pressured and rapid, words spilling out faster than they can be assembled into coherent sentences. There is a grandiosity, a sense of inflated capability and importance that can feel genuinely convincing in the moment. Energy surges through the body, demanding expression in movement, pacing, gesticulation. Unlike the stuporous delirium of datura, benzydamine's altered state is awake, active, and agitated.

The hallucinations emerge within this stimulated matrix, creating a deeply disorienting combination of perceptual distortion and manic energy. Shadows acquire depth and intention. Figures appear at the periphery of vision and may persist when directly observed. Sounds acquire phantom echoes and undertones. The quality of the hallucinations is more akin to hypnagogic imagery than the fully realized phantom interactions of tropane deliriants -- flickering, partially formed, more suggestive than definitive. But the stimulation makes them harder to dismiss; the racing mind seizes on each perceptual anomaly with urgent interest rather than dreamy acceptance.

The body is caught between competing pharmacological forces. The stimulation produces restlessness, jaw tension, and a tremor in the hands that can progress to frank shaking at higher doses. Nausea is common and can be severe. The heart pounds with uncomfortable force, its rhythm sometimes irregular. Temperature may rise. The mouth is parched but the stomach rebels against the idea of drinking. There is a pervasive physical discomfort that the stimulation prevents you from ignoring -- unlike sedating deliriants, where the body's complaints are muffled by drowsiness, benzydamine keeps you awake and aware of every unpleasant sensation.

The duration is moderate -- four to eight hours of primary effects -- and the decline brings a gradual replacement of stimulation with exhaustion. The hallucinations fade before the agitation does, leaving a period of uncomfortable wakefulness stripped of its perceptual distortions. Sleep, when it finally arrives, is fitful and shallow, the body too depleted for deep rest but too tired to remain awake. The morning after carries a heavy fatigue, a headache, and a lingering nausea that can persist well into the following day.

Mechanism of Action

Benzydamine's anti-inflammatory effects are distinct from classical NSAIDs. It inhibits the production and activity of proinflammatory cytokines — particularly tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) — rather than blocking prostaglandin synthesis via COX inhibition. It also exhibits local anaesthetic properties through sodium channel blockade, accounting for the characteristic numbing effect of topical preparations.

Psychoactive Mechanism

The mechanism underlying benzydamine's deliriant effects is not fully characterized. Unlike classical anticholinergic deliriants (atropine, scopolamine, diphenhydramine), benzydamine is not a primary muscarinic receptor antagonist. Its hallucinogenic and dissociative properties are thought to involve a combination of mechanisms:

• Sigma receptor agonism — Benzydamine shows affinity for sigma-1 and sigma-2 receptors, which may contribute to its dissociative-like qualities
• Non-competitive NMDA receptor antagonism — Some evidence suggests weak channel-blocking activity at glutamate NMDA receptors
• Local anaesthetic effects spreading systemically — At high doses, sodium channel blockade may affect central neural transmission
• Possible serotonergic activity — Some structural similarity to indole compounds; extent of serotonergic binding is unclear

The result is a confusing, often terrifying altered state that does not map cleanly onto any single substance class — users report simultaneously delirious, dissociative, and stimulant-like qualities.

Pharmacokinetics

Oral benzydamine is rapidly absorbed with peak plasma concentrations within 1–2 hours. It undergoes extensive first-pass metabolism. The drug and its metabolites are primarily excreted renally. At toxic doses, accumulation of metabolites may contribute to prolonged adverse effects including cardiac arrhythmias.

Origins and Development

Benzydamine was developed by the Italian pharmaceutical company Angelini in the 1960s. It was synthesized as part of a research program aimed at identifying non-steroidal anti-inflammatory compounds, and was found to have an unusual combination of anti-inflammatory, analgesic, antipyretic, and local anaesthetic properties. It was approved and marketed across Europe, Asia, South America, and elsewhere as a topical treatment for oral and oropharyngeal conditions under the Tantum Verde brand, as well as under numerous generic and regional trade names.

Recognition as a Drug of Abuse

The abuse potential of benzydamine was not recognized at the time of its introduction. Reports of recreational misuse emerged gradually from several geographic regions — particularly South Africa, Eastern Europe, and parts of Latin America — where over-the-counter availability and low price relative to other drugs of abuse made it accessible to populations seeking psychoactive effects.

Case reports began appearing in the medical literature in the 1990s and 2000s documenting serious adverse events in individuals who had ingested large quantities of benzydamine-containing mouthwash. Emergency physicians noted a consistent presentation: severe agitation, bizarre behavior, hallucinations, tachycardia, and occasional seizures.

Regulatory Response

Following recognition of abuse patterns, several countries moved to restrict OTC availability of benzydamine preparations or reformulate them to reduce the concentration of active ingredient. In South Africa, benzydamine mouthwash was subjected to prescription control in some pharmacy chains. Despite these measures, benzydamine abuse continues to be documented in harm reduction literature and emergency medicine case series.

Current Status

Benzydamine remains a widely used and effective topical anti-inflammatory medication. Its reputation as a substance of abuse is largely a footnote to its mainstream pharmaceutical history — the vast majority of benzydamine use worldwide is therapeutic. The drug remains available OTC in many countries for its intended uses, with regulatory decisions varying considerably by jurisdiction.