Proxibarbal is a non-sedative barbiturate with a specific anti-serotonin and anti-histamine effect, due to enzyme induction of serotoninase and histaminase. Its lack of unpleasant side-effects. Proxibarbal exists in ring-chain tautomeric equilibrium with the two diastereomers of valofan. Proxibarbal is metabolized to a five-membered lactone. Its only barbituric property is its ability to induce enzymes that destroy a surplus of neurohormones and rid people of their neurovegetative sufferings, including migraine and other types of vascular headache. Side effects are: dizziness, drowsiness, dyspepsia, allergic reactions. Proxibarbal enhances the effects of other depriving agents, including alcohol.