Declare @Id Int                               
Select @Id = Id From sysobjects Where Name = 'TblDrugUse'
if  not Exists(SELECT * FROM syscolumns WHERE id = @Id and Name = 'Daily')
  Alter table TblDrugUse add Daily  real null

  Select @Id = Id From sysobjects Where Name = 'TblDrugUse'
if  not Exists(SELECT * FROM syscolumns WHERE id = @Id and Name = 'Qty_Consum')
  Alter table TblDrugUse add  Qty_Consum  real null