In most cases, if your child is poisoned, you should just call Poison Control right away using the toll-free nationwide number:
1-800-222-1222
You should not wait for your child to have symptoms, even if you aren't positive if your child actually swallowed any of the poison, or if you aren't sure if it really is poisonous. And don't call your pediatrician first to ask if you should call Poison Control. If your child had contact with something that could be poisonous, your best bet is to just call Poison Control.
In certain cases, like if your child is having seizures, is not breathing, or is unresponsive, then you should call 911 instead.
What is a Poison?
If your child drinks mouthwash, eats holly berries, or gets drain cleaner on her hands, do you still call poison control? Yes.
Understanding what actually is a poison confuses a lot of parents, since many the definition too literally, thinking a poison is just something like 'rat poison' or an insecticide. Instead, according to the American Association of Poison Control Centers, a poison is 'any product or substance that can harm someone if it is used in the wrong way, by the wrong person, or in the wrong amount. Examples of possible poisons include some household products, chemicals at work or in the environment, drugs (prescription, over-the-counter, herbal, illegal or animal medicines), snake bites, spider bites, and scorpion stings.'
As your baby begins to get more mobile, in addition to knowing the number to Poison Control, it becomes very important to get your home childproofed and be sure that all dangerous items, including poisonous plants, household cleaners, pesticides, alcoholic beverages, medications, gasoline are stored safely and out of reach of children.
Source: American Association of Poison Control Centers. What Is a Poison? Fact Sheet.

