Causes of Lethargy in Toddlers

Most of the time, your toddler is probably a bundle of energy that you have a hard time keeping up with. But if your toddler has been lethargic lately, there's probably something going on. Lethargy isn't simply being more tired than normal, however. It's a more extreme condition that warrants medical attention. Know the signs and symptoms of lethargy so you'll be able to get your child exactly what he needs to recover.


Many parents will exclaim that their extremely tired and cranky child is lethargic, but that's not the correct definition. True lethargy is almost as if your child were in a coma, according to the AskDr.Sears website. If your child is truly lethargic, she'll have a hard time talking, won't make eye contact, won't be coherent enough to realize that you're near her, won't be able to walk or sit up and will be limp and lifeless. Your toddler will act and look very sick if she's lethargic, and chances are your gut will immediately tell you that something's wrong.

Head Injury

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A head injury is one of the most common reasons why your child would be truly lethargic. If your toddler has recently fallen down and bonked her head, keep an eye on her to see if she develops the symptoms of lethargy in the minutes and hours afterwards. In the case of serious bumps, you should call your doctor right away anyway, and he'll tell you exactly what to be on the lookout for. If your toddler immediately loses consciousness with a head injury, head to the emergency room right away, cautions Robert H. Pantell, M.D., author of "Taking Care of Your Child: A Parent's Illustrated Guide to Complete Medical Care." The loss of consciousness can indicate bleeding in the brain, which is probably what's causing the lethargy. Signs of a serious head injury also include eye pupils that aren't the same size.

Medical Causes

Certain illnesses can lead to lethargy and knowing what to look for will help you act immediately. Influenza might be what's causing your toddler to be lethargic, and it's one of the more common medical reasons why your toddler is laying around and not acting like herself. Being overheated because of high temperatures of being overdressed can also lead to lethargy, according to David B. Jacoby, M.D., R. M., author of "Encyclopedia of Family Health." Other conditions, though scary, aren't as common. These include a brain tumor, leukemia, blood poisoning, hepatitis, meningitis and a lack of oxygen to the brain.

What to Do and Considerations

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If your child is lethargic, call his pediatrician right away or head straight to the emergency room. According to the AskDr.Sears website, true lethargy usually indicates a serious illness and it requires immediate medical attention. Before you freak out completely, ask yourself if your child is truly lethargic or if he's just really tired. If he hasn't been sleeping well, he's probably just tired. Examine him to help put your mind at ease. If he'll respond to you and make eye contact, he's probably just extra tired. If he can speak and move around on his own, he's probably not truly lethargic, either. However, if you're ever in doubt, there's nothing wrong with erring on the side of caution and calling your child's doctor.