Dear shanmugam i can understand your concern. There is nothing to get alarmed because this is a natural happening in the course of diabetes progression. Along with time in diabetes the medication will tend to become less effective this is due to the progressive damage of pancreas in diabetes. To study the status of pancreas you need to do some test like C-peptide assay This test will tell you ,How much insulin is there in pancreas? Usually in diabetes after 15 yrs the insulin production will drop very low and most of patients need to take insulin. The medication given to you are 1.stugeron---cinnarizine 2.vertin---Betahistine 3.Dizitac---cinnarizine 20mg + DimenHydrinate 40mg the last medication Dizitac is a combination medication which is more effective than stugeron This medications are used in middle ear problems like 1.Symptoms caused by balance or movement problems such as vertigo, 2.tinnitus, and Ménière s disease 3.Travel sickness Regards