Having dropped some ecstasy, calling nurse? (5)
I believe the answer is:
carer
'nurse?' is the definition.
(a nurse cares for patients)
'having dropped some ecstasy calling' is the wordplay.
'having dropped' suggests deleting specific letters.
'some ecstasy' becomes 'E' (informal term for the drug).
'calling' becomes 'career' (synonyms).
'career' with 'e' taken away is 'CARER'.
(Other definitions for carer that I've seen before include "One looking after an invalid" , "Breathe out" , "Raising of a siege; financial assistance" , "One who tends" , "Helper for infirm person" .)