- Subjects who are taking, or have taken, certain prescribed drugs in the four weeks prior to Day 0 and in particular topical or systemic steroids, anti-inflammatory, anti-coagulant, antiproliferative drugs and antibiotics Certain drugs are not excluded in this trial, including OTC analgesics such as paracetamol and codeine, vitamin and mineral supplements and OTC cold remedies and hormonal contraceptives. If antibiotics are required after Day 0, this will not exclude subjects from continuation in this trial and the data will be recorded in the CRF