Volcy-Gómez M
New England Center for Headache, Stamford, CT, USA.
Rev Neurol. 2004;39(4):388-93.
Primary headaches (PH), which are highly prevalent pathologies, are linked to high morbidity and disability rates and high costs for the health care system. Due to the partial effectiveness of prophylactic treatments, especially in chronic headaches, or the existence of contraindications that make them unsuitable for prescription, the use of botulinum toxin (BTX) arises as a promising preventive therapy.
The purpose of this study was to determine the usefulness and the mechanism of action of BTX in PH through a review of the literature.
Recent results of BTX use in PH are contradictory and, although controlled studies with placebos are scarce, it has been suggested that it could have a grade II-III evidence level of effectiveness and safety, with greater benefits in refractory chronic migraine and chronic tension-type headache, together with the absence of analgesic abuse and psychiatric illness. The probable mechanism of action in PH is through a peripheral antinociceptive effect related to a decreased release of neuropeptides and to the transmission of impulses with indirect inhibition of nociceptive centres in the brain stem, which is an effect that is apparently intensified with repeated applications. A correlation has been claimed between the use of BTX and a reduction in the intensity, severity, number of headaches per month, diminished use of analgesics per month and lowered total management costs. Side effects of the treatment are infrequent (< 1%) and transient.
Despite findings that have proved BTX to be effective and safe as prophylactic therapy in PH, it is still not considered to be the first choice preventive treatment. Further studies are needed to establish sites, doses and application schemas (fixed vs. mobile), as well as a subtype of patients who can benefit from its use.
原发性头痛（PH）是一种高发性疾病，与高发病率、高致残率以及医疗保健系统的高成本相关。由于预防性治疗的效果有限，尤其是在慢性头痛方面，或者存在使它们不适合处方的禁忌症，肉毒杆菌毒素（BTX）的使用成为一种有前景的预防性治疗方法。
本研究的目的是通过文献综述确定BTX在PH中的有效性和作用机制。
BTX用于PH的近期结果相互矛盾，尽管缺乏安慰剂对照研究，但有人认为其有效性和安全性的证据水平可能为II-III级，对难治性慢性偏头痛和慢性紧张型头痛有更大益处，同时不存在镇痛药物滥用和精神疾病。BTX在PH中的可能作用机制是通过外周抗伤害感受作用，这与神经肽释放减少以及通过间接抑制脑干中的伤害感受中枢来传递冲动有关，这种作用显然会随着重复应用而增强。有人声称BTX的使用与头痛强度、严重程度、每月头痛次数的减少、每月镇痛药使用量的减少以及总管理成本的降低之间存在相关性。治疗的副作用很少见（<1%）且是短暂的。
尽管研究结果证明BTX作为PH的预防性治疗有效且安全，但它仍不被视为首选的预防性治疗方法。需要进一步研究以确定部位、剂量和应用方案（固定剂量与可变剂量），以及能够从其使用中受益的患者亚型。
