Asthma symptoms- PEC or similar

Anti-histamines are your best bet for stopping or mitigating to some level the flare ups.  Best to see your doctor about it as he can possibly prescribe something with very little side effects that might suit him.  Also ask your doctor for a referral to the local hospital's chest clinic and see if they can tweak his medication (asthmatics should ideally never need to use the blue inhaler, although in practice it never worked out that way for me).  They may also be able to offer you advice on getting him to identify when he has a problem.  But from past experience, when you are 8 and you have a flare up it has to have a profound effect on you (inability to breathe) before you will actually use the inhaler.  In a child with ASD it may never be possible to get them to identify and use, not at 8 anyway. When I was at primary school I would run around and play until it reached the point at which I could no longer walk due to the asthma attack being almost full blown.  Once I got to secondary school I started to take a bit more notice of it and took a more hands on approach to dealing with it.

A suggestion might be to give him 3 cards, one red, one yellow and one green.  Write on each what he needs to do  for the given colour.  So Green is ok or im fine, so write about continuing with what he does.  Yellow is wheezy slightly out of breath, so write on the card "Use your inhaler and sit down and relax".  Red is asthma attack or serious level, maybe write "use your inhaler twice and get help".  Get him to carry the cards on him and ask him from time to time to describe his asthma using the cards.  if he feels fine its a green card and he should do what it says on the card. If he feels wheezy its the yellow card and he needs to do what it says on the card.  If its the red card he needs to do what it says on the card.  Overtime he will stop using the cards and just do what it says on the cards.  Or at least he might do.  But that would seem a possible strategy, by associating the problem and the action with an outcome he has to do.  Also let his school know about it and encourage him to use the same system at school if he needs to.

Thank you for taking the time to reply. 
It may be a sensory reason behind him not instigating use of his inhalers. Because he doesn’t complain and co-operates if I ask him to use them I dismissed this. There are other things I ask him to do and he will refuse or at least argue the point! 
Hopefully if I get any more replies they might be helpful for you too. 

Personally, I forget until I get too bad. I'm usually engrossed in something else 

I don’t think my response will be of much if any help for you but I am keen to see what responses you get on this. I am now in my mid twenties and still struggle to regularly use my inhalers and for me I’m pretty sure part of my struggle is a sensory issue. 

I go through phases and have done since I was diagnosed as asthmatic at the age of 7. I don’t cope/enjoy taking the brown preventer as to me it leaves what feels like a coat of something at the back of your throat and I find I gag at times taking this which in turn leads me to get back into a routine of avoiding using it.

Then my asthma will flare up and I will beat myself up for not using the preventer like I should and will only use my blue when I get to the point that I am really wheezy and having coughing fits (more so on a night for me) 

I have also found I have been given different advice from the Asthma clinic over the last few trips and now trying to fully understand what being asthmatic means and how it works. It was explained to me that as a long term condition it’s finding out how to manage your Asthma that is key and that the preventer for me can be used up and down in volume depending how I am feeling (can seem quite confusing I think I would prefer a set pattern of when I’m supposed to take it and how much) so if I’m not really feeling symptoms of my asthma and it seems to be at bay I should reduce the dose on the preventer and shouldn’t be using the reliever. If I find I need the reliever that’s when I need to be upping my dose on the preventer until I get to the point I don’t need to reach for the reliever.

I’m still trying to work it out and what works best for me, I have until my next review to try this new plan and see how I get on but then the option would be to discuss alternative treatments and I have been made aware there is a tablet form (but I’m not very good at taking some types of tablets so I am not certain that would be a better option for me) 

Sorry if this isn’t very helpful for you but I would like to see what advice others may have on this as I am still struggling to manage as an adult, as far as I’m aware it’s something I’ve always battled with and part of me also was embarrassed as a youngster I had already felt different enough and been bullied at school and didn’t want to highlight something else - kids can be cruel. I hit secondary school and threw myself into sports and although exercise can sometimes add to the triggers (especially cold mornings) I’m sure over the years I helped my asthma through improving the strength of my lungs. I had a bad knee injury 2 years ago and after surgeries and multiple treatments I found after this injury and not exercising like I was before my asthma is now as bad as it has ever been. Whether there’s any science in that I’m not sure but for me I do feel my asthma wasn’t as bad when I was physically fit, it hadn’t gone but definitely wasn’t as bad as it is now.