Due to the potential for concomitant psychiatric illness and substance use disorders, understanding the potential interactions between psychotropics and drugs of abuse is important.

  • What are the potential drug-drug interactions between illicit drugs and medications?1-3
  • How does cigarette smoking (polycyclic aromatic hydrocarbons) affect medications?4-5
  • What are possible drug interactions in patients that consume alcohol?6-7
  • How do opioids and benzodiazepines interact? What is the clinical significance of the combination?8-10
  • How do drugs of abuse interact with anti-retroviral therapies?11-12
  • How do natural or synthetic cannabis interact with medications?13-18

Reviewer 1: Carley Rainey, PharmD, BCPS
Reviewer 2: Katy L. Zeier, PharmD, BCPP
Reviewer 3: Austin Smith, PharmD, BCPP
2023-2024 AAPP Resident and New Practitioner Committee


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  2. Abbott KL, Flannery PC, Gill KS et al. Adverse pharmacokinetic interactions between illicit substances and clinical drugs. Drug Metab Rev. 2020; 52(1): 44-65. [PubMed]     
  3. Lindsey WT, Stewart D, Childress D. Drug interactions between common illicit drugs and prescription therapies. Am J Drug Alcohol Abus. 7th ed. 2012;38(4):334-43. DOI: 10.3109/00952990.2011.643997. PubMed PMID: 22221229.
  4. Kroon LA. Drug interactions with smoking. Am J Health Syst Pharm. 2007;64(18):1917-21. DOI: 10.2146/ajhp060414. PubMed PMID: 17823102.
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  10. U.S. Food and Drug Administration. FDA Drug Safety Communication: FDA urges caution about withholding opioid addiction medications from patients taking benzodiazepines or CNS depressants: careful medication management can reduce risks. 2017. [Weblink]
  11. Desai N, Burns L, Gong Y, et al. An update on drug-drug interactions between antiretroviral therapies and drugs of abuse in HIV systems. Expert Opin Drug Metab Toxicol. 2020;16(11):1005-1018. [PubMed]
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  13. Arellano AL, Papaseit E, Romaguera A, Torrens M, Farré M. Neuropsychiatric and General Interactions of Natural and Synthetic Cannabinoids with Drugs of Abuse and Medicines. CNSNDDT. 2017;16(5):554-566. DOI: 10.2174/1871527316666170413104516. PubMed PMID: 28412920.
  14. Kong TY, Kim JH, Kim DK, Lee HS. Synthetic cannabinoids are substrates and inhibitors of multiple drug-metabolizing enzymes. Arch Pharm Res. 2018;41(7):691-710. [PubMed]
  15. Brown JD, Winterstein AG. Potential adverse drug events and drug-drug interactions with medical and consumer cannabidiol (CBD) use. J Clin Med. 2019;8(7):989. [PubMed]
  16. Qian Y, Gurley BJ, Markowitz JS. The Potential for Pharmacokinetic Interactions Between Cannabis Products and Conventional Medications. J Clin Psychopharmacol. 2019;39(5):462-471. [PubMed]
  17. Brown JD. Potential adverse drug events with tetrahydrocannabinol (THC) due to drug-drug interactions. J Clin Med. 2020;9(4):919. [PubMed]
  18. Doohan. PT, Oldfield LD, Arnold JC, Anderson, LL. Cannabinoid Interactions with Cytochrome P450 Drug Metabolism: a Full-Spectrum Characterization. AAPS J. 2021 Jun 28;23(4):91. [Pubmed]