PRE-EMPTIVE PHARMACOGENOMICS IN ACUTE CARE SETTINGS WITH HEALTH ECONOMIC EVALUATIONS (PHOENIX TRIAL)

Inclusion Criteria INPATIENTS Age ≥18 years * Capable of giving informed consent directly or via a legal representative (e.g., next of kin, welfare guardian, health care power of attorney). * Participants who are newly prescribed one of the trial-eligible index drugs during their hospital stay may be approached for consent. Consent should be obtained within 3 days of the first dose of the index drug being administered. If there is a clear clinical plan documented on HEPMA indicating that the patient will be started on an eligible drug (but has not yet received the first dose), consent may be obtained in anticipation. However, formal trial enrolment will only occur once the first dose of the index drug has been administered. * Participant must not have a prescription for this drug in the previous 3 months. * Participant is able to provide a cheek swab * Participant is able to take part and be followed-up for at least 12 weeks. * Participant is resident in NHSGGC health board area OUTPATIENTS * Age ≥18 years * Capable of giving informed consent directly or via a legal representative (e.g., next of kin, welfare guardian, health care power of attorney). * Participants who are expected to be prescribed a trial-eligible drug during their outpatient clinic visit may be approached for consent prior to starting the medication. In these cases, formal trial enrolment will only occur once the patient has confirmed that they have received and started the prescribed medication * Participant must not have a prescription for this drug in the previous 3 months. * Participant is able to provide a cheek swab * Participant is able to take part and be followed-up for at least 12 weeks. * Participant is resident in NHSGGC health board area. Exclusion Criteria INPATIENTS * Inability to give informed consent directly or via a legal representative. * Non-English speakers without translation support. * Participants co-enrolled in other trials where a medication is one of the index drug is part of the trial protocol. * Inability to give informed consent directly or via a legal representative. * Non-English speakers without translation support. * Participants co-enrolled in other trials where a medication is one of the index drug is part of the trial protocol. * Life expectancy estimated to be less than 6 months by treating clinical team. * Severe illness limiting participation (investigator discretion). * Duration of index drug total treatment length is planned to be less than seven consecutive days. * Not registered with a General Practitioner. * No fixed address. * Participant is, in the opinion of the Investigator, not suitable to participate in the trial. * Participant has existing impaired hepatic or renal function for which a lower dose or alternate drug selection is already part of current routine care. * Estimated glomerular filtration rate greater than 15 ml/min/1.73m2 (except for participants with a renal transplant commenced on tacrolimus, who may be included regardless of eGFR, provided they are not on dialysis).eGFR result obtained at screening or within the last 6 months or patients record confirming history of CKD 5 * Participants on any form of dialysis. * Participant with advanced liver failure (stage Child-Pugh C). * Participants with liver transplant. * Participants with allogeneic haematopoietic stem cell transplant. * Participants previously enrolled in the PHOENIX trial. * Participant who has declined participation and has declined reapproach for subsequent drugs. * Index drug exceeding trial drug cap. OUTPATIENTS * Inability to give informed consent directly or via a legal representative. * Non-English speakers without translation support. * Participants co-enrolled in other trials where a medication is one of the index drug is part of the trial protocol. * Life expectancy estimated to be less than 6 months by treating clinical team. * Severe illness limiting participation (investigator discretion). * Duration of index drug total treatment length is planned to be less than seven consecutive days. * Not registered with a General Practitioner. * No fixed address. * Participant is, in the opinion of the Investigator, not suitable to participate in the trial. * Participant has existing impaired hepatic or renal function for which a lower dose or alternate drug selection is already part of current routine care. * Estimated glomerular filtration rate greater than 15 ml/min/1.73m2 (except for participants with a renal transplant commenced on tacrolimus, who may be included regardless of eGFR, provided they are not on dialysis)..eGFR result obtained at screening or within the last 6 months or patients record confirming history of CKD 5. * Participants on any form of dialysis. * Participant with advanced liver failure (stage Child-Pugh C). * Participants with liver transplant. * Participants with allogeneic haematopoietic stem cell transplant. * Participants previously enrolled in the PHOENIX trial. * Participant who has declined participation and has declined reapproach for subsequent drugs. * Index drug exceeding trial drug cap. Re-approach Criteria: Previously declined patients will only be re-approached in subsequent admissions six-months after the first approach. \* We wish to ensure that no more than 20% of participants are included on the basis of any single index drug. The numbers recruited on each index drug will be monitored and recruitment on specific drugs may be limited, or paused, at times throughout the study. This process will be administered by the Trial Management group, and monitored by the Trial Steering Committee.