Formula in Carton

Hi Helen

I take this opportunity to thank you for your last reply which was very useful to us.

I have read one of your advices re formula in carton, that you can place the carton under the blanket of eiderdown to keep it warm at body temperature and ready for use.

I would like to know whether I can use the same carton later, should I not use it right away?

We always carry a carton of formula in the car, is this alright?