Blake Alexia, Wan Bo Angela, Malek Leila, DeAngelis Carlo, Diaz Patrick, Lao Nicholas, Chow Edward, O'Hearn Shannon
MedReleaf, Markham, Ontario, Canada.
Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.
Ann Palliat Med. 2017 Dec;6(Suppl 2):S215-S222. doi: 10.21037/apm.2017.08.05. Epub 2017 Aug 23.
Insufficient management of cancer-associated chronic and neuropathic pain adversely affects patient quality of life. Patients who do not respond well to opioid analgesics, or have severe side effects from the use of traditional analgesics are in need of alternative therapeutic op-tions. Anecdotal evidence suggests that medical cannabis has potential to effectively manage pain in this patient population. This review presents a selection of representative clinical studies, from small pilot studies conducted in 1975, to double-blind placebo-controlled trials conducted in 2014 that evaluated the efficacy of cannabinoid-based therapies containing tetrahydrocannabinol (THC) and cannabidiol (CBD) for reducing cancer-associated pain. A review of literature published on Medline between 1975 and 2017 identified five clinical studies that evaluated the effect of THC or CBD on controlling cancer pain, which have been reviewed and summarised. Five studies that evaluated THC oil capsules, THC:CBD oromucosal spray (nabiximols), or THC oromucosal sprays found some evidence of cancer pain reduction associated with these therapies. A variety of doses ranging from 2.7-43.2 mg/day THC and 0-40 mg/day CBD were administered. Higher doses of THC were correlated with increased pain relief in some studies. One study found that significant pain relief was achieved in doses as low as 2.7-10.8 mg THC in combination with 2.5-10.0 mg CBD, but there was conflicting evidence on whether higher doses provide superior pain relief. Some reported side effects include drowsiness, hypotension, mental clouding, and nausea and vomiting. There is evidence suggesting that medical cannabis reduces chronic or neu-ropathic pain in advanced cancer patients. However, the results of many studies lacked statistical power, in some cases due to limited number of study subjects. Therefore, there is a need for the conduct of further double-blind, placebo-controlled clinical trials with large sample sizes in order to establish the optimal dosage and efficacy of different cannabis-based therapies.
对癌症相关的慢性疼痛和神经性疼痛管理不足会对患者生活质量产生不利影响。对阿片类镇痛药反应不佳或使用传统镇痛药有严重副作用的患者需要其他治疗选择。轶事证据表明，医用大麻有潜力有效管理这类患者的疼痛。本综述介绍了一系列有代表性的临床研究，从1975年进行的小型试点研究到2014年进行的双盲安慰剂对照试验，这些研究评估了含四氢大麻酚（THC）和大麻二酚（CBD）的大麻素类疗法减轻癌症相关疼痛的疗效。对1975年至2017年间发表在Medline上的文献进行回顾，确定了五项评估THC或CBD对控制癌症疼痛效果的临床研究，并对其进行了回顾和总结。五项评估THC油胶囊、THC:CBD口腔黏膜喷雾剂（纳布西莫尔）或THC口腔黏膜喷雾剂的研究发现，有证据表明这些疗法与癌症疼痛减轻有关。使用的THC剂量范围为2.7 - 43.2毫克/天，CBD剂量范围为0 - 40毫克/天。在一些研究中，较高剂量的THC与疼痛缓解增加相关。一项研究发现，低至2.7 - 10.8毫克THC与2.5 - 10.0毫克CBD联合使用时可实现显著的疼痛缓解，但关于更高剂量是否能提供更好的疼痛缓解存在相互矛盾的证据。一些报告的副作用包括嗜睡、低血压、精神模糊以及恶心和呕吐。有证据表明医用大麻可减轻晚期癌症患者的慢性或神经性疼痛。然而，许多研究结果缺乏统计学效力，在某些情况下是由于研究对象数量有限。因此，需要进行更多大样本量的双盲、安慰剂对照临床试验，以确定不同大麻素类疗法的最佳剂量和疗效。
