when the first time patient 94293 was prescribed a medication in 01/2104 via the ivpca route?
select prescriptions.startdate from prescriptions where prescriptions.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 94293 ) and prescriptions.route = 'ivpca' and strftime('%y-%m',prescriptions.startdate) = '2104-01' order by prescriptions.startdate asc limit 1