Database: hospital_1
Question: Find the names of patients who are not using the medication of Procrastin-X.
SQL: select name from patient except select t1.name from patient as t1 join prescribes as t2 on t2.patient  =  t1.ssn join medication as t3 on t2.medication  =  t3.code where t3.name  =  'procrastin-x'