how many hours has it been since last time patient 99883 was prescribed clotrimazole during this hospital visit?
select 24 * ( strftime('%j',current_time) - strftime('%j',prescriptions.startdate) ) from prescriptions where prescriptions.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 99883 and admissions.dischtime is null ) and prescriptions.drug = 'clotrimazole' order by prescriptions.startdate desc limit 1