until 06/2105 what was the first time patient 80119 had a medication via iv drip route prescribed?
select prescriptions.startdate from prescriptions where prescriptions.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 80119 ) and prescriptions.route = 'iv drip' and strftime('%y-%m',prescriptions.startdate) <= '2105-06' order by prescriptions.startdate asc limit 1