RESUMO
Cupping Therapy (CT) is an ancient method and currently used in the treatment of a broad range of medical conditions. Nonetheless the mechanism of action of (CT) is not fully understood. This review aimed to identify possible mechanisms of action of (CT) from modern medicine perspective and offer possible explanations of its effects. English literature in PubMed, Cochrane Library and Google Scholar was searched using key words. Only 223 articles identified, 149 records screened, and 74 articles excluded for irrelevancy. Only 75 full-text articles were assessed for eligibility, included studies in this review were 64. Six theories have been suggested to explain the effects produced by cupping therapy. Pain reduction and changes in biomechanical properties of the skin could be explained by "Pain-Gate Theory", "Diffuse Noxious Inhibitory Controls" and "Reflex zone theory". Muscle relaxation, changes in local tissue structures and increase in blood circulation might be explained by "Nitric Oxide theory". Immunological effects and hormonal adjustments might be attributed to "Activation of immune system theory". Releasing of toxins and removal of wastes and heavy metals might be explained by "Blood Detoxification Theory". These theories may overlap or work interchangeably to produce various therapeutic effects in specific ailments and diseases. Apparently, no single theory exists to explain the whole effects of cupping. Further researches are needed to support or refute the aforesaid theories, and also develop innovative conceptualizations of (CT) in future.
RESUMO
BACKGROUND: Wet cupping is a widely used traditional therapy in many countries, which justifies a continuous scientific evaluation of its efficacy and safety. OBJECTIVES: To perform a systematic review to critically evaluate and update the available evidence of wet cupping in traditional and complementary medicine. METHODS: Ten electronic databases were searched from their inceptions to February 2016. Included studies were randomized clinical trials (RCTs) that evaluated wet cupping against any type of control interventions in patients with any clinical condition, as well as healthy individuals. Cochrane risk of bias tool was used to appraise the included RCTs. RESULTS: Fourteen RCTs met the eligibility criteria. The included studies evaluated the following clinical conditions: nonspecific low back pain (NSLBP), hypertension, brachialgia, carpal tunnel syndrome (CTS), chronic neck pain, metabolic syndrome, migraine headaches, oxygen saturation in smokers with chronic obstructive pulmonary disease (COPD), and oral and genital ulcers due to Behçet disease. Two RCTs evaluated physiologic and biochemical parameters of healthy individuals. Overall, 9 RCTs favored wet cupping over various control interventions in NSLBP (n = 2), hypertension (n = 1), brachialgia (n = 1), CTS (n = 1), chronic neck pain (n = 2), oxygen saturation in smokers with COPD (n = 1), and oral and genital ulcers due to Behçet disease (n = 1). Five RCTs showed no statistically significant between-group differences: NSLBP (n = 1), metabolic syndrome (n = 1), migraine headaches (n = 1), and physiologic and biochemical parameters of healthy individuals (n = 2). Included RCTs had a variable risk of bias across all domains and suffered methodologic limitations. CONCLUSIONS: There is a promising evidence in favor of the use of wet cupping for musculoskeletal pain, specifically NSLBP, neck pain, CTS, and brachialgia. Better-quality trials are needed to generate solid evidence and firmly inform policy makers.
