and mechanical ventilation is needed in people who are approaching respiratory arrest; however, there is no evidence from clinical trials to support this. For those with severe persistent asthma not controlled by inhaled corticosteroids and LABAs, bronchial thermoplasty may be an option. It involves the delivery of controlled thermal energy to the airway wall during a series of bronchoscopies. While it may increase exacerbation frequency in the first few months it appears to decrease the subsequent rate. Effects beyond one year are unknown. Monoclonal antibody injections such as mepolizumab, dupilumab, or omalizumab may be useful in those with poorly controlled atopic asthma. However, as of 2019 these medications are expensive and their use is therefore reserved for those with severe symptoms to achieve cost-effectiveness. Monoclonal antibodies targeting interleukin-5 (IL-5) or its receptor (IL-5R), including mepolizumab, reslizumab or benralizumab, in addition to standard care in severe asthma is effective in reducing the rate of asthma exacerbations. There is limited evidence for improved health-related quality of life and lung function. Evidence suggests that sublingual immunotherapy in those with both allergic rhinitis and asthma improve outcomes. It is unclear if non-invasive positive pressure ventilation in children is of use as it has not been sufficiently studied. Alternative medicine Many people with asthma, like those with other chronic disorders, use alternative treatments; surveys show that roughly 50% use some form of unconventional therapy. There is little data to support the effectiveness of most of these therapies. Evidence is insufficient to support the usage of vitamin C or vitamin E for controlling asthma. There is tentative support for use of vitamin C in exercise induced bronchospasm. Fish oil dietary supplements (marine n-3 fatty acids) and reducing dietary sodium do not appear to help improve asthma control. In people with mild to moderate asthma, treatment with vitamin D supplementation may reduce the risk of asthma exacerbations, however, it is not clear if this is only helpful for people who have low vitamin D levels to begin with (low baseline vitamin D). There is no strong evidence to suggest that vitamin D supplements improve day-to-day asthma symptoms or a person's lung function. There is no strong evidence to suggest that adults with asthma should avoid foods that contain monosodium glutamate (MSG). There have not been enough high-quality studies performed to determine if children with asthma should avoid eating food that contains MSG. Acupuncture is not recommended for