what are the top five drugs to be prescribed to patients in their 20s during this year?
select t1.drug from ( select prescriptions.drug, dense_rank() over ( order by count(*) desc ) as c1 from prescriptions where prescriptions.hadm_id in ( select admissions.hadm_id from admissions where admissions.age between 20 and 29 ) and datetime(prescriptions.startdate,'start of year') = datetime(current_time,'start of year','-0 year') group by prescriptions.drug ) as t1 where t1.c1 <= 5