Friend, depending on the type of spray that was used will depend on the potential for toxicity. Drooling certainly could be a sign of ingestion some of the chemicals. Or, it could be a sign of something completely different like: Nausea, oral discomfort, etc. This is what you can do:
1- Give him some milk; if he did ingest some of the chemical the milk will help dilute it.
2- Start him on Pepcid AC (famotidine) 10mg 1/2 tablet every 12 hours. You can buy pepcid ac over the counter in any pharmacy.
3- Do Not give things like pepto bismol.
4- Symptoms that would require a vet visit are: Anorexia, lethargy, tremors, difficulty walking, vomiting excessively, etc.
5- If he is still drooling in the morning after doing the above I would have him checked by family veterinarian.
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