In a study comparing the central nervous depression due to supra-therapeutic doses of triazolam (a benzodiazepine), pentobarbital (a barbiturate) and gamma-hydroxybutyric acid, it appeared as if GHB had the strongest dose-effect function. Since gamma-hydroxybutyric acid has a high correlation between its dose and its central nervous system depression, it has a high risk of accidental overdose. In the case of accidental overdose of gamma-hydroxybutyric acid, patients can become drowsy, fall asleep and may enter a coma.