instruction: what was the name of the drug prescribed to patient 22756, two times until 17 months ago?
response: SELECT t1.drug FROM (SELECT prescriptions.drug, COUNT(prescriptions.startdate) AS c1 FROM prescriptions WHERE prescriptions.hadm_id IN (SELECT admissions.hadm_id FROM admissions WHERE admissions.subject_id = 22756) AND DATETIME(prescriptions.startdate) <= DATETIME(CURRENT_TIME(), '-17 month') GROUP BY prescriptions.drug) AS t1 WHERE t1.c1 = 2