Delta-9-tetrahydrocannabinol (thc) - Sulfamethoxazole Interaction
Herbal: Delta-9-tetrahydrocannabinol (thc)
Also Known As: BHO, Black Glass, Budder, Butane Hash Oil, Butane Honey Oil, Butter, Dabs, Delta-9 Tetrahydrocannabinol, Delta-9 THC, Delta-9-THC, Dronabinol, Honeycomb
Drug: Sulfamethoxazole
Brand names:
Gantanol
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 25, 2025
Interaction Details
Sulfamethoxazole is classified as belonging to the following category: Cytochrome P450 2C9 (Cyp2C9) Inhibitors
Theoretically, drugs that are CYP2C9 inhibitors might increase the levels and adverse effects of THC.
THC is a substrate of CYP2C9 enzymes.
Interaction Rating
Likelihood of Occurrence
PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
References
- Product information for Marinol. AbbVie. North Chicago, IL 60064. August 2017. Available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/018651s029lbl.pdf.
Interaction Details
Sulfamethoxazole is classified as belonging to the following category: Cytochrome P450 2C9 (Cyp2C9) Substrates
Theoretically, THC might increase the levels and adverse effects of CYP2C9 substrates.
In vitro research shows that THC moderately inhibits the CYP2C9-mediated 7-hydroxylation of S-warfarin in a concentration-dependent manner. In vitro research also shows that cannabis extracts containing THC modestly inhibit the CYP2C9 metabolism of tolbutamide; extracts providing the specific cannabinoids cannabidiol (CBD) or cannabigerol (CBG) alone had stronger inhibitory effects than extracts containing both THC and CBD. Theoretically, THC may inhibit the metabolism of other CYP2C9 substrates. Conversely, a crossover clinical study in healthy adults shows that oral THC does not inhibit CYP2C9.
Interaction Rating
Likelihood of Occurrence
UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
References
- Damkier P, Lassen D, Christensen MMH, Madsen KG, Hellfritzsch M, Pottegård A. Interaction between warfarin and cannabis. Basic Clin Pharmacol Toxicol. 2019;124(1):28-31.
- Treyer A, Reinhardt JK, Eigenmann DE, Oufir M, Hamburger M. Phytochemical comparison of medicinal cannabis extracts and study of their CYP-mediated interactions with coumarinic oral anticoagulants. Med Cannabis Cannabinoids. 2023;6(1):21-31.
- Bansal S, Zamarripa CA, Spindle TR, et al. Evaluation of Cytochrome P450-Mediated Cannabinoid-Drug Interactions in Healthy Adult Participants. Clin Pharmacol Ther 2023.
Delta-9-tetrahydrocannabinol (thc) Overview
Delta-9-tetrahydrocannabinol (THC), also known as tetrahydrocannabinol, is a cannabinoid. It is one of the over 80 constituents, known as cannabinoids, that have been identified from Cannabis sativa. THC is the major psychoactive compound of cannabis and is most often associated with the plant's recreational use. THC is known to produce a range of effects on the body and mind, including relaxation, altered senses, and changes in mood and cognition. THC has also been used to treat pain and anxiety symptoms.
Delta-9-tetrahydrocannabinol (thc) - More Interactions
Delta-9-tetrahydrocannabinol (thc) interacts with 1070 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
| Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
| Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
| Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
| Unknown | No interactions have been reported or no interaction data is currently available. |
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Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Drug descriptions are provided by MedlinePlus.
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Dr. Brian Staiger, PharmD
In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!
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