Mr Briggs is a 65 year old male and has a complex medical history including Ischaemic Heart Disease, Atrial Fibrillation, Asthma, Pulmonary hypertension and Schizophrenia. He has a 40-year pack history, continues to smoke and has previously declined smoking cessation advice or referral. However, reviewing him following his discharge with a NSTEMI, he is keen to stop smoking. Mr Briggs agrees to a referral to the smoking cessation service but intends to stop smoking immediately. You discuss the common withdrawal symptoms and review his medication.
Which one of the following medications is least likely to need its dose reducing?