instruction: what were the four most commonly prescribed drugs for patients that had previously received vasopressors - phenylephrine (neosynephrine) within 2 months, since 2100?
response: SELECT t3.drugname FROM (SELECT t2.drugname, DENSE_RANK() OVER (ORDER BY COUNT(*) DESC) AS c1 FROM (SELECT patient.uniquepid, treatment.treatmenttime FROM treatment JOIN patient ON treatment.patientunitstayid = patient.patientunitstayid WHERE treatment.treatmentname = 'vasopressors - phenylephrine (neosynephrine)' AND STRFTIME('%y', treatment.treatmenttime) >= '2100') AS t1 JOIN (SELECT patient.uniquepid, medication.drugname, medication.drugstarttime FROM medication JOIN patient ON medication.patientunitstayid = patient.patientunitstayid WHERE STRFTIME('%y', medication.drugstarttime) >= '2100') AS t2 ON t1.uniquepid = t2.uniquepid WHERE t1.treatmenttime < t2.drugstarttime AND DATETIME(t2.drugstarttime) BETWEEN DATETIME(t1.treatmenttime) AND DATETIME(t1.treatmenttime, '+2 month') GROUP BY t2.drugname) AS t3 WHERE t3.c1 <= 4