In summarizing clinical studies investigating potential drug-drug interactions between hemp seed oil and commonly prescribed drugs, it is crucial to note that limited research has been conducted in this area. HSO, primarily valued for its nutritional content, such as omega-3 and omega-6 fatty acids, is distinct from psychoactive THC-containing hemp products. While interactions with prescription drugs are generally considered low, it is noteworthy that a trace amount of CBD is present in HSO composition, as demonstrated by Leizer et al. in 2000. CBD, a bioactive, non-narcotic compound in HSO, has gained popularity for its potential therapeutic properties [8]. The growing demand for HSO and CBD-related products, coupled with research confirming their nutritional and therapeutic benefits, has led many individuals to consider their use alongside prescription medications. Therefore, seeking personalized guidance from healthcare professionals when contemplating concurrent use, especially with medications metabolized by the liver, is essential, as theoretical interactions may pose safety concerns.
While HSO is less likely to impact drug metabolism compared to CBD directly, individual responses to HSO can vary. Monitoring drug concentrations when incorporating hemp seed oil into one's routine is advisable, particularly for medications with a narrow therapeutic range. HSO does not significantly reduce the effectiveness of commonly prescribed drugs. However, for drugs that necessitate specific dietary considerations, it is essential to be aware of the potential for HSO to affect drug absorption. This ensures that previously prescribed medications continue functioning as intended and minimizes the risk of adverse effects.
Several studies have investigated the potential interactions of cannabidiol with various medications. Anderson et al. (2021) discovered that CBD can inhibit the metabolism of citalopram and escitalopram, potentially resulting in elevated plasma concentrations and adverse effects [59]. Szaflarski et al. (2019) reported a bidirectional drug-drug interaction between CBD and clobazam, which increased levels of active metabolites for both compounds [60]. Nasrin et al. (2023) found that CBD inhibits nicotine metabolism, potentially influencing tobacco addiction and cessation efforts [61]. Bacle et al. (2022) discussed a case where CBD use resulted in a drug interaction with tacrolimus, an immunosuppressant commonly prescribed after kidney transplantation [62]. Furthermore, CBD generally exhibits a low potential for drug interactions with anti-seizure medications, except when combined with clobazam, as suggested by Patsalos et al. (2020) and VanLandingham et al. (2020) [63, 64].
In another line of research, Evans et al. (2023) identified an additive pharmacological interaction between CBD and tramadol when used to treat diabetic neuropathic pain [65]. Guedon et al. (2023) identified 90 cannabidiol-drug interactions among cancer patients, with central nervous system depression and hepatotoxicity being the primary risks [66]. Wray et al. (2023) demonstrated that co-administration of CBD and everolimus resulted in increased systemic exposure to everolimus, indicating a pharmacokinetic interaction [67]. A case report by Anderson et al. (2022) addressed a potential interaction between CBD and Fluoxetine [68].
Additionally, Singh et al. (2020) highlighted a drug-drug interaction between CBD and lithium, which might be associated with CBD-induced renal dysfunction and elevated creatinine levels in patients with epilepsy [69]. Madden et al. (2020) proposed a case report detailing a clinically significant drug interaction between methadone and CBD attributed to inhibiting CYP3A4 and CYP2C19 enzymes involved in methadone metabolism [70]. Parihar et al. (2022) reported a case in which chronic co-administration of CBD reduced tamoxifen metabolites by inhibiting CYP3A4 and CYP2D6 [71]. Cortopassi (2020) supported an interaction between cannabidiol and warfarin through the blockade of CYP2C9 [72]. An animal study by Vázquez et al. (2020) confirmed drug-drug interactions between CBD and various analgesic drugs used for chronic pain [73]. Lastly, Brown et al. (2023) presented a case report demonstrating a potential interaction between CBD and clopidogrel, an antiplatelet medication, possibly through P2Y12 inhibitors [74].
In addition, phase IV clinical studies conducted by eHealthMe using FDA data reported no drug interactions between HSO and medications such as Plavix, Tacrolimus, Citalopram hydrobromide, Celebrex, Methotrexate, and Folic acid. However, a few drug interaction cases were noted between HSO and Lexapro. These findings emphasize the importance of individualized guidance and healthcare professional consultation when considering the co-use of HSO or CBD-related products alongside prescribed medications.