I've been thinking about this for a while (mainly since I got to the point where I need to double breakfast time to fit them all in), & have read a couple of posts as well on the issue of how long you should leave between inhaler puffs.
When I was a lad & first got an inhaler (Intal), & through my time on Ventolin, Becotide, etc, I was always told to leave 2 minutes. This apparently was to give my lungs a rest between doses & allow the medicine to absorb.
I read somewhere else though that you should leave 30 seconds, the reason being to allow pressurised inhalers to recharge.
Does anyone actually know what is truth & what has just grown as mythology over the years? I take Symbicort as one of my inhalers for example, which doesn't have a pressurised canister, so could I take two one after the other? Or, could I take (say) Ventolin, then Symbicort while the Ventolin recharges, or would that put pressure on my lungs?