Try Melatonin. You can get it overcounter at the pharmacy.
take it 20 mins before bed when you change shift for a day or 2 then get off it.
It will readjust yer internal clock without making you drowsey.
Doesnt work for all, but it works for me.
I just force myself back onto local hours right away and adjust. I resist naps until I've been back for at least a week, but I do fall asleep pretty early in the evening and wake with the chickens those first few days back.