In Australia, I imagine similar to UK, they are very strict about the co-mingling of drug use and medical practice. My advice? Don't say anything. Lie if necessary! I base this on two stories. Two of my friends are doctors. Both were reported for drug use. Both were capable doctors. I suspect family in one case. After hearings at the Health Care Complaints Commission, both were allowed to continue working but were put under "conditions" - scheduled (more than weekly) + random urine and blood tests to monitor total abstinence (paid out of their personal pockets); all their patient care to be supervised by a senior doctor; ongoing counselling and NA meetings; and they were banned from prescribing any "drugs of addiction" - so no benzos, opioids etc (any cases had to be referred to their supervisor or a colleague). HCCC cases and conditions are up on a public website for anyone to see. One friend managed to get his conditions lifted after 8 - count them EIGHT - years of constant hoop jumping. The other friend showed a couple of dirty urines (out of hundreds) and was struck off. He can reapply after a certain number of years, if he keeps jumping the hoops and recording clean urines in the meantime. This is all supposedly in the name of protecting the patient. If they get even a sniff of previous drug use, they may insist on urine testing and put in on your record. Seriously: don't say anything!!! It is none of their business. There are very few careers that will accept even past use. Medicine is not one of them. It such a conservative field.