Senegal with asthma

by Fay. N.
(Norfolk, GB)

My 16 yr old Senegal has attacks of asthma fairly frequently. We observe it happening around once a fortnight on av. but of course we don't know how he is when we're out.

He starts by "sneezing" for 10-15 mins.The tail movements become more and more extreme. This usually worsens until he is wheezing loudly, trying to shake mucus from his beak, stretching his neck out and opening his beak as if trying to clear something in his mouth. He gets very worried and initially tries to talk. It can take an hour or more to subside

We have tried removing/changing foodstuffs, changing the paper on the bottom of his cage, moving him to another room. No noticeable difference.

Is there anything more we can try short of invasive proceedures? Other indoor birds are present, also dogs.

Cooking and the coal fire do not affect him.
Thank you for any help you can offer. I wish there was something we could spray near him like my own asthma inhalers, to relieve his symptoms, but I doubt this would be sensible. (Husband = retired vet.)