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List of Tier I and Tier II drugs. Tier II drugs can be both individually named drugs and classes of drugs (e.g., atypical antipsychotics).

Description

This image is Figure 1 in the article "Drug-Impaired Driving: The Contribution of Emerging and Undertested Drugs."

Tier I Drugs

  • Cannabinoids
    • Δ9-THC
    • Carboxy-THC
    • 11-hydroxy-THC
  • CNS Stimulants
    • Methamphetamine
    • Amphetamine
    • MDMA
    • MDA 
    • Cocaine
    • Benzoylecgonine
  • CNS Depressants
    • Carisoprodol
    • Meprobamate
    • Alprazolam
    • Alpha-hydroxyalprazolam
    • Clonazepam
    • 7-Aminoclonazepam
    • Lorazepam
    • Diazepam
    • Nordiazepam
    • Oxazepam
    • Temazepam
  • Narcotic Analgesics
    • Codeine
    • 6-MAM
    • Buprenorphine
    • Fentanyl
    • Hydrocodone
    • Hydromorphone
    • Methadone
    • Morphine
    • Oxycodone
    • Oxymorphone
    • Tramadol
    • O-Desmethyltramadol

Tier II Drugs

  • Cannabinoids
    • Synthetic Cannabinoids
  • CNS Stimulants
    • Cathinones
    • Methylphenidate
    • Mitragynine
  • CNS Depressants
    • Atypical Antipsychotics
    • Barbiturates
    • Carbamazepine
    • Chlordiazepoxide
    • Chlorpheniramine
    • Diphenhydramine
    • Doxylamine
    • Gabapentin
    • GHB
    • Hydroxyzine
    • Lamotrigine
    • Mairtazapine
    • Novel Benzodiazepines
    • Phenytoin
    • Pregabalin
    • Secobarbital
    • Topiramate
    • Trazadone
    • Tricyclic Antidepressants
    • Valproic Acid
    • Zopiclone
  • Narcotic Analgesics
    • Fentanyl Analogs
    • Novel Opioids
    • Tapentadol
  • Dissociative Drugs*
    • Dextromethorphan
    • Ketamine
    • PCP
  • Inhalants*
    • Difluoroethane
    • Inhalant Class
  • Hallucinogens*
    • Hallucinogens