Phase I: To develop and validate laboratory urine and blood test for the detection of medications commonly used in the treatment of asthma Phase II: to test the developed assay in the clinic, to determine its practicality to conduct, and its clinical utility in adherence assessment.

Phase I: laboratory based study to develop LC-MS/MS assay of urine / blood to detect presence or lack asthma medication in 50 volunteers with asthma. Phase II: once the test is validated it will be tested in a 100 patients attending the asthma clinics to test its clinical utility. Urine and blood samples will be collected from patients at time of clinic attendance to test for asthma medication panel and outcome will determine adherence or non-adherence. Clinical outcomes of adherent versus non adherent groups will be compared in terms of asthma control, lung function, biomarkers FeNO and blood eosinophils, exacerbation frequency and hospitalisation.

Inclusion Criteria:

1. Aged 18-80
2. Able to give valid informed consent
3. Prescribed one or more of the medications to be tested
4. Able to provide a blood and urine sample
5. Able to complete questionnaires in English

Exclusion Criteria:

1. Females who are pregnant or lactating.
2. Patients known to have any blood borne virus that would render the sample hazardous. This includes Hepatitis B, Hepatitis C and HIV.

Patients will be identified at the BRSAS, general asthma clinics and as inpatients admitted to wards at HEFT. The research team will approach patients in these settings.