A large amount of poppy seeds can cause severe central nervous system damage in dogs. Immediately contact your veterinarian or the ASPCA Pet Poison Helpline if you believe your dog has consumed a large quantity of the seeds.
Can dogs eat muffins with poppy seeds?
Can Dogs Eat Poppy Seed Muffins? – No, poppy seed muffins should not be fed to dogs. A single muffin might only cause an upset stomach, but eating too many could result in a toxic reaction. Even if they have no immediate reaction to the muffins, it is best to keep them away from baked goods because the sugar and carbohydrates may increase their risk of obesity. 
Bagels can cause bloating, vomiting, constipation, or diarrhea in dogs.
What is an acceptable quantity of poppy seeds?
For complete safety, experts recommend consuming no more than 1 tablespoon of raw poppy seeds per 7 pounds (lb) of body weight. This means that a person weighing 150 lb (70 kg) should not consume more than 7 tablespoons of raw poppy seeds at a time.
