The invention relates to the use of argon (Ar) gas for producing all or part of an inhalable medicinal product intended to prevent or treat a neurointoxication in humans. The medicinal product contains argon in an effective proportion and acts on at least one brain receptor in order to regulate the functioning of dopamine-, glutamate-, serotonin-, acetylcholine-, taurine-, GABA- and/or noradrenalin-mediated neuro-transmission systems. Preferably, the proportion by volume of argon in the gaseous medicinal product is between 15 and 80%. The neurointoxication is chosen from excitotoxicities engendering a state of addiction, acute cerebral accidents, neurodegenerative diseases, and psychiatric or neurological pathologies, in particular anxiety conditions, psychotic conditions, in particular schizophrenia, and epilepsy in its various forms.