"Urinary and stomach pH levels can have a strong effect on DL-amphetamine
(Adderal) excretion and absorption. An acidic stomach and GI pH will decrease the absorption of Adderall
and acidic urine levels will decrease the reabsorption of the drug
through the renal system. Co-administration of acidic substances (e.g., citric acid) causes decreased renal reabsorption of DL-amphetamine; whereas, alkaline agents (e.g., antacids) may cause a marked increase in renal tubular reabsorption. The increased reabsorption can increase the retention of amphetamines, with potential to result in dangerously high serum levels." - Delmar's Drug Reference for Health Care Professionals. p10.
Your pet could be experiencing tolerance, but the above is also possible. I would say it can not and should not be smoked - hes inhaling binders for the most part, and any amounts of adderal in the pills contents would likely get destroyed by the heat of its combustion, which is likely why it did nothing. I dont believe Adderall XR can easily or effectively be made into a freebase, which tend to have lower smoke points than what would destroy the chemical in bound form.
Here is a post detailing intranasal
Its recommended you take half the amount up your nose that you would normally eat, as it will hit harder but it wont last as long.
My best advice is to try a normal dose orally on a settled, non-acidic stomach. If that doesnt give the desired effect, try insufflation
the next time the drug is used, but be cautious doing so for the first time when it has also been taken orally. Also make sure your pet is cautious in any attempts to forcibly alter stomach acidity via alkalization, it can apparently lead to dangerous levels of amphetamine in the blood.