Lucy is a 32 year old accountant and has had Asthma since early childhood. She is otherwise fit and well, with no drug allergies and just has mild Eczema. She is finding that over the last 2 months, despite using her inhaled corticosteroid (ICS) inhaler twice daily she is still getting night time Asthma symptoms around 4 times a week and using her Salbutamol inhaler twice in a week. Her inhaler technique is good and her observations and respiratory exam are normal. There are no clear trigger factors in her history.
What is the single most appropriate next step in her management?