Library

Metapirilen

Methapyrilene is an antihistamine and anticholinergic of the pyridine chemical class which was developed in the early 1950s. It was sold under the trade names Co-Pyronil and Histadyl EC in the UK. It has relatively strong sedative effects, to the extent that its primary use was as a medication for insomnia rather than for its antihistamine action. Together with scopolamine, it was the main ingredient in Sominex, Nytol, and Sleep-Eze. It also provided the sedative component of Excedrin PM. All of these products were reformulated in the late 1970s when methapyrilene was demonstrated to cause liver cancer in rats when given chronically.

Metapirilen molecular structure
Metapirilen molecular structure diagram from the DrugsPRO substance library.

Classification

  • Psychoactive: Depressant

Effects

  • Sedation
  • Motor Impairment
  • Reduced Anxiety
  • Anxiety Suppression
  • Dulled Perception

Routes of Administration

No route information available yet.

Harm Reduction

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Sources

Substance data is aggregated from the following public harm-reduction and reference sources.

Links

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Methapyrilene - DrugsPRO vodič za tvari

Methapyrilene: Methapyrilene is an antihistamine and anticholinergic of the pyridine chemical class which was developed in the early 1950s. It was sold under the trade names Co-Pyronil and Histadyl EC in the UK. It has relatively strong sedative effects, to the extent that its primary use was as a m

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