what is the dose of phenylephrine hcl, that patient 12274 was first prescribed in 01/2105?
select prescriptions.dose_val_rx from prescriptions where prescriptions.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 12274 ) and prescriptions.drug = 'phenylephrine hcl' and strftime('%y-%m',prescriptions.startdate) = '2105-01' order by prescriptions.startdate asc limit 1