Fortunately (for me, at least) I've never had experience with the drugs that you've mentioned but you will probably find that a lot of that is behind you already if you've been eating healthy for 2 years.
Working while fasting is not really conducive to getting best results from either but if that is the best option you have, just allow an extra safety margin when handling machinery, tricky accounts or what have you. You will probably find that you have increased mental clarity and gain an efficiency advantage which might lead to overworking. Hopefully, it will lead to putting your feet up as you keep ahead of schedule!
Keep your water intake up so that the body can efficiently flush away the released toxins. 2 litres is often quoted as a minimum starting point by some fasting supervisors. On my last fast, I was drinking between 1.5 and 2.5 every day but later on I increased to 3+ and really felt the toxins start to flow.