Friend, chocolate toxicity is very dependent on the amount consumed, weight, of the patient and type of chocolate. In this case, if the coating of chocolate was light and standard size candies it is likely that your dog will not develop life-threatening symptoms, but, can develop gastrointestinal symptoms like vomiting, diarrhea, etc. If you have access to pick up hydrogen peroxide 3% within the hour you can get him to vomit with peroxide. This is what you can do:
1- Give him 1/2 tablespoon of hydrogen peroxide 3% orally to get him to vomit.
2- Allow him to walk for a minute and move his belly to mix stomach content with peroxide. If he does not vomit within 5-10 minutes, repeat it again. Can give a total of 3 times 5-10 minutes apart.
3- If he does not vomit after 3rd dose or you do not see the chocolate in the vomit, observe him for the next 24 hours. If he becomes hyperactive, muscle tremors, changes in respiration, etc. have him checked immediately by ER veterinarian, these are symptoms that could progress to life-threatening seizures or cardiac arrhythmias. If no symptoms after 24 hours (especially the first 12 hours), unlikely for any symptoms to develop.
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