Summarize this article:

Even medicine designed to treat fevers and colds in children can cause reactions in some children. If your child starts to exhibit symptoms of an allergic reaction or if they’re experiencing serious side effects, call your doctor for medical advice. They may advise you to go to the emergency room or they may prescribe a different medication. If your child starts to have trouble breathing, pain or pressure in their chest or abdomen, or their skin turns a bluish or gray color, seek emergency medical attention immediately. Mild symptoms of dehydration such as being extra thirsty and dry mouth are normal with a fever. But if your child starts to exhibit serious symptoms such as dizziness, decreased urine output or dark urine, and extreme sleepiness, then you need to get them medical treatment.  Your child may need IV fluids in order to be rehydrated. If your child is unable to hold down any liquids and exhibits signs of dehydration due to vomiting or diarrhea, call your doctor for medical advice. Other symptoms of severe dehydration include headache, few or no tears, and dry skin and lips. A very high fever can be extremely dangerous, especially for children. If your child’s fever gets too high, it can lead to serious medical issues and possibly death. Bring your child to an emergency room if their fever gets above 102 °F (39 °C). For infants, contact your doctor if they have any fever at all. It could be a sign of a serious infection. A fever should run its course naturally and go away after about 2-3 days. A fever that lasts longer than 3 days could be a sign of a more serious issue. Call your doctor if your child’s fever persists past 3 days. They may want to assess or have you take your child to an emergency room.  Your doctor may also prescribe medication to help treat the fever. If you have a child younger than 2 and their fever lasts more than 24 hours, call your doctor. Even a low-grade fever can be harmful to children with certain conditions. If your child has a chronic medical problem such as lupus, cancer, or heart disease and they develop a fever, contact your doctor. They may want to take precautionary measures or monitor your child. It’s also important to consider any other symptoms that present along with a fever. Pay attention to anything you’ve noticed or that your child has complained about. Call your child’s doctor right away if your child is:  Listless or irritable Vomiting repeatedly or has diarrhea Not capable of maintaining eye contact with you Refusing fluids or can’t keep them down Peeing less than usual, crying without tears, or less alert than usual Complaining of an earache, sore throat, pain while urinating, or another specific complaint Developing a rash If your child has a fever along with other severe symptoms, this may indicate a medical emergency. Call emergency services in your country or take your child to the emergency department of your nearest hospital if your child is:  Crying without stopping Extremely irritable or fussy Sluggish and finding it difficult to wake up Developing a rash that looks like purple spots or bruises Turning blue around their lips, nails, and tongue Complaining of a stiff neck, trouble breathing, abdominal pain, or severe headache Going limp or refuses to move Leaning forward and drooling Having seizures

Summary:
Call your doctor if your child reacts to any medications. Get medical attention if your child shows serious signs of dehydration. Seek emergency medical help if your child’s fever gets worse. Talk to your doctor if your child’s fever lasts more than 72 hours. Contact your doctor if your child has a pre-existing condition. Watch for symptoms that may indicate a problem. Go to an emergency room if your child has severe symptoms.