There is much misunderstanding about insulin storage — many are told that they should always keep insulin cool. This is not necessarily the case. Insulin is a live substance, if it is ill, it looks ill, so take a look at it if you are in doubt. Your blood sugars will soon tell you if your insulin has become inactive. You should have spares with you, but if they have also been affected, then you probably need to go to your local GP or pharmacist or even the nearest hospital to get more insulin.