you can use ...

if object_id('dbo.yourtable') is not null

begin

drop table dbo.yourtable

end

Keep in mind this is not a best practice because you need elevated auth to be able to drop or create a table.

- maybe # temp tables may help out (I don't know the procs functional needs)

- To avoid everyone executing the proc needs to be dbo-member, you could use the with execute as setting.

(check BOL)