Patient description: A 4 year old boy presents to the emergency room with wheezing. He has had a history of allergic rhinitis, but no history of wheezing. His mother reports that 5 hours ago patient was playing in the backyard sandbox when she heard him suddenly start coughing. The coughing lasted only moments, but he has been audibly wheezing since. Mother was concerned, because his breathing has not returned to normal, so she brought him to the ED. On exam, the child is playful and well appearing. Wheezing is heard in the mid-right chest area. O2 sats are 100% on room air.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Asthma Subjects eligible for enrolment in the study must meet all of the following Informed consent: Subjects must be able to provide informed consent, have their consent signed and dated Type of subject: Subjects with documented GP diagnosis of asthma as their primary respiratory disease Current Anti-Asthma Therapy: All subjects must be prescribed maintenance therapy and receiving ICS with or without LABA (either a fixed combination or via separate inhalers), and for at least 4 weeks prior to Visit 2 Other background asthma medication such as anti-leukotrienes are permitted All subjects on ICS monotherapy or ICS/LABA combination (this can be a fixed dose combination or an ICS alone or LABA alone in separate inhalers) must have had symptoms in the past week prior to Visit 2. Symptoms are defined by daytime symptoms more than twice per week, use of short-acting beta2-agonist bronchodilator more than twice per week, any limitation of activities, or any nocturnal symptoms/awakening. (The symptoms are based on subject's recall and are consistent with the GINA and in principal with the BTS/SIGN guidelines) Subject questionnaires: Subjects must be able to complete the electronic subject questionnaires as well as those questionnaires that are completed by phone or provide a proxy e.g. a partner/relative/a friend who can do so on their behalf Gender and Age: Male or female subjects aged ≥18 years of age at Visit 1. A female is eligible to enter and participate in the study if she is of Non-child bearing potential (i.e. physiologically incapable of becoming pregnant, including any female who is post-menopausal or surgically sterile). Surgically sterile females are defined as those with a documented hysterectomy and/or bilateral oophorectomy or tubal ligation. Post-menopausal females are defined as being amenorrhoeic for greater than 1 year with an appropriate clinical profile, e.g. age appropriate, history of vasomotor symptoms. However in questionable cases, a blood sample with FSH > 40MIU/ml and estradiol <40pg/ml (<147 pmol/L) is confirmatory OR Child bearing potential has a negative urine pregnancy test at Visit 2, and agrees to one of the highly effective and acceptable contraceptive methods used consistently and correctly (i.e. in accordance with the approved product label and the instructions of the physician for the duration of the study  Subjects meeting any of the following must not be enrolled in the study Recent history of Life-threatening asthma: Defined for this protocol as an asthma episode that required intubation and/or was associated with hypercapnea, respiratory arrest or hypoxic seizures within the last 6 months COPD Respiratory Disease: A subject must not have current evidence or GP diagnosis of chronic obstructive pulmonary disease Other diseases/abnormalities: Subjects with historical or current evidence of uncontrolled or clinically significant disease. Significant is defined as any disease that, in the opinion of the GP/ Investigator, would put the safety of the subject at risk through participation, or which would affect the efficacy or safety analysis if the disease/condition exacerbated during the study Drug/food allergy: Subjects with a history of hypersensitivity to any of the study medications (e.g., beta2-agonists, corticosteroid) or components of the inhalation powder (e.g., lactose, magnesium stearate). In addition, subjects with a history of severe milk protein allergy that, in the opinion of the GP/ Investigator, contraindicates the subject's participation will also be excluded Investigational Medications: A subject must not have used any investigational drug within 30 days prior to Visit 2 or within five half-lives (t½) of the prior investigational study (whichever is longer of the two), (if unsure discuss with the medical monitor prior to screening) Chronic user of systemic corticosteroids: A subject who, in the opinion of the GP/Investigator, is considered to be a chronic user of systemic corticosteroids for respiratory or other indications (if unsure discuss with the medical monitor prior to screening) Subjects who are using LABA without an ICS as asthma maintenance therapy Subjects who plan to move away from the geographical area where the study is being conducted during the study period and/or if subjects have not consented to their medical records being part of the electronic medical records database that is operational in the Salford area