Cannabis is one of the most widely used recreational drugs in the world [1]. It has been documented that some people diagnosed with cancer use cannabis to alleviate some of their symptoms, including pain, nausea, vomiting, stress, and lack of appetite [1–3]. Cannabis use is becoming increasingly popular for the management of cancer-related symptoms, with some patients incorporating it as a regular self-management behaviour [4–6]. Several surveys report cannabis use as ranging from 13 to 24% in this population [4, 7, 8].

Cannabis use for the management of cancer-related symptoms may have numerous benefits, including improved quality of life and potentially better adherence to chemotherapy and radiotherapy treatments [6]. Cannabis has chemical properties that may help reduce or control various adverse symptoms, such as cancer-associated pain [9–11]. It may also mitigate chemotherapy-induced nausea and vomiting [12–14], as well as sleep disorders [1]. Cancer patients sometimes use medical cannabis as complementary pain relief [15].

Although cannabis is traditionally been associated with inhalation, routes of administration have diversified in recent years, in conjunction with the legalization of cannabis in various North American jurisdictions [16]. Thus, medical cannabis is no longer administered via a single route, but instead is found in many forms, including tablets (i.e. Nabilone), sprays (i.e. Nabiximol), creams, edible products, or oils [16–19].

However, cannabis can cause various side effects, including respiratory problems (e.g. coughing) [20]; for people with predispositions, its use can also be associated with certain mental health problems, such as depression, mania, and psychosis [21–24]. Some authors also point out that regular cannabis use may affect cognitive functions (e.g. decreased attention and reflexes) and induce structural, functional, and chemical changes in the brain in people with predispositions [25–28]. To ensure safe use of medical cannabis by people diagnosed with cancer, oncology care providers must have the knowledge, skills, and open-mindedness to discuss patients’ needs and preferred routes of administration [29, 30]. However, many healthcare providers report not feeling adequately equipped to discuss the various aspects of medical cannabis use, such as patients’ reasons for use, the approved indications, and the possible routes of administration [29, 31–33].

A preliminary search of the Cumulative Index to Nursing and Allied Health Literature (CINAHL) showed no review of the literature has yet mapped the reasons for the use of medical cannabis, the indications for the prescription of cannabis, and the routes of administration based on the experiences of patients diagnosed with cancer and of their healthcare providers. The knowledge syntheses found in our search often present the efficacy of cannabis in managing the various symptoms cancer patients experience, such as chemotherapy-induced nausea and vomiting [12, 34], cancer pain [35, 36], or cancer cachexia [37]. We retrieved only two knowledge syntheses on the use of cannabis and its administration in oncology [18, 19]; however, neither included qualitative evidence from primary empirical studies, surveys, or grey literature. By deepening our understanding of optimal approaches for supporting patients’ decision-making around medical cannabis use and for providing high-quality care to people diagnosed with cancer, a synthesis of qualitative evidence from patient and/or provider experiences is expected to add to the current state of knowledge. Furthermore, as some authors point out [19], it would be appropriate for oncology care providers to become more familiar with the routes of administration, dosage, and potential risks of medical cannabis, and to make recommendations in consequence.

In light of our findings, the reasons for medical cannabis use by people diagnosed with cancer should be highlighted, since they may differ from approved-medical indications. This scoping review aims to map the current literature on the use of medical cannabis in oncological settings based on the experiences of patients diagnosed with cancer and their healthcare providers.