title: Herbal Highs: Review on Psychoactive Effects and Neuropharmacology.
abstract: BACKGROUND
  A new trend among users of new psychoactive substances' the consumption of "herbal highs": plant parts containing psychoactive substances. Most of the substances extracted from herbs, in old centuries were at the centre of religious ceremonies of ancient civilizations. Currently, these herbal products are mainly sold by internet web sites and easily obtained since some of them have no legal restriction.
  
  
  OBJECTIVE
  We reviewed psychoactive effects and neuropharmacology of the most used "herbal highs" with characterized active principles, with studies reporting mechanisms of action, pharmacological and subjective effects, eventual secondary effects including intoxications and/or fatalities Method: The PubMed database was searched using the following key.words: herbal highs, Argyreia nervosa, Ipomoea violacea and Rivea corymbosa; Catha edulis; Datura stramonium; Piper methysticum; Mitragyna speciosa.
  
  
  RESULTS
  Psychoactive plants here reviewed have been known and used from ancient times, even if for some of them limited information still exist regarding subjective and neuropharmacological effects and consequent eventual toxicity when plants are used alone or in combination with "classical" drugs of abuse.
  
  
  CONCLUSIONS
  Some "herbal highs" should be classified as harmful drugs since chronic administration has been linked with addiction and cognitive impairment; for some others taking into consideration only the recent trends of abuse, studies investigating these aspects are lacking.
authors: Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome. Italy.
authors: Silvia
authors: S
authors: Graziano
authors: Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, College Lane Campus, University of Hertfordshire, Hatfield, Herts, AL10 9AB. United Kingdom.
authors: Laura
authors: L
authors: Orsolini
authors: Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome. Italy.
authors: Maria Concetta
authors: MC
authors: Rotolo
authors: Unit of Forensic Toxicology (UoFT), Department of Anatomical, Histological, Forensic and Orthopedic Sciences, Sapienza University of Rome, Rome. Italy.
authors: Roberta
authors: R
authors: Tittarelli
authors: Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, College Lane Campus, Hatfield, Herts, AL10 9AB, UK. United Kingdom.
authors: Fabrizio
authors: F
authors: Schifano
authors: Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome. Italy.
authors: Simona
authors: S
authors: Pichini
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects*; D016206:Databases, Bibliographic / Q000706:statistics & numerical data; D006801:Humans; D013287:Illicit Drugs; D009480:Neuropharmacology; D028321:Plant Preparations / Q000009:adverse effects* / Q000737:chemistry; D011619:Psychotropic Drugs / Q000009:adverse effects* / Q000737:chemistry
chemical_list: D013287:Illicit Drugs; D028321:Plant Preparations; D011619:Psychotropic Drugs
keywords: Herbal highs; neuropharmacology; plant material; psychoactive herbal products