It depends on the type of insulin you are taking at the moment. If the insulin you are taking remains the same, then there wont be any change in terms of the dose you should take. for example, if you take Actrapid 6 units through injection, and if you take the same insulin through a pen now, the dose will remain the same at 6 units. on the other hand, it you change the type of insulin as well apart from delivery device, you should always reduce the dose by 20% to begin with and slowly build the dose up bases on home
sugar readings
Hope this helps.