Acetaminophen: Watch dosage for children

Acetaminophen overdoses are serious, and they can occur all too easily. Here's how to protect your child, and when to seek emergency care.

Acetaminophen (Tylenol, others) has long been the standard remedy for fever and pain in children. After all, it's safe, effective and readily available without a prescription. But even good things, in excess, can be harmful. Here's what you need to know about acetaminophen overdoses and children.

How do acetaminophen overdoses occur?

Acetaminophen overdoses are serious, and they can occur all too easily. Consider these scenarios:

• You're in a hurry. You might unwittingly give your child too much acetaminophen if you don't take the time to carefully measure the medication.
• You combine medications. If your child has various cold symptoms, you might combine acetaminophen with a cold remedy. But this can be dangerous because many cold medications already contain acetaminophen.
• You use the wrong formulation. You might cause an overdose if you give your child adult acetaminophen tablets instead of the children's formulation. Even the children's versions of acetaminophen come in many different formulations, and the dosage varies for each one. For example, infant drops are three times as concentrated as the elixir or syrup typically given to toddlers. If you assume that both liquids contain the same amount of medicine, substituting infant drops for syrup could result in a dose of acetaminophen three times what it should be.
• You decide that more is better. If you're not satisfied with the performance of the recommended dosage of acetaminophen, you might increase the dosage and cause an accidental overdose.
• Your child mistakes the medication for candy or juice. Overdoses also can occur when children, particularly toddlers, discover the medicine on their own and mistake it for something safe to eat or drink.

How much acetaminophen is too much?

If you give your child acetaminophen, it's important to stick to the recommended dosage. Too much acetaminophen overloads the liver's ability to process the drug safely. An acetaminophen overdose can lead to life-threatening liver and kidney problems.

Many factors determine how severely a particular dose of acetaminophen can damage the liver. For example, children younger than age 5 seem to be less susceptible to liver damage than are older children and adults. The amount of food in your child's stomach when the medication is ingested also is a factor.

In general, a single toxic dose of acetaminophen for a child is more than 68 milligrams (mg) per pound of the child's weight, or more than 150 mg per kilogram of the child's weight. That equals about 1,360 mg for a child who weighs 20 pounds or 2,040 mg for a child who weighs 30 pounds. For perspective, adults may take 325 mg or 500 mg of acetaminophen every three or four hours as needed, up to 4,000 mg in 24 hours.

How is an acetaminophen overdose treated?

If your child ingests more than the recommended amount of acetaminophen but not enough to cause a toxic reaction, medical care isn't likely necessary. Be cautious, however. If you're concerned about a possible acetaminophen overdose or notice early signs or symptoms of an overdose — nausea, vomiting, lethargy and abdominal pain — call your child's doctor or local poison control center or seek emergency care.

In the emergency room, a child with an acetaminophen overdose may be given activated charcoal to decrease absorption of the acetaminophen. Activated charcoal is usually given as a black liquid drink, but it can be given through a tube inserted through the mouth or nose and into the stomach if necessary. If the overdose is severe, the child may need an antidote to reverse the effects of the acetaminophen. The antidote should be given within eight to 10 hours after the acetaminophen is ingested.

Left untreated, a serious acetaminophen overdose may be fatal within a few days. But careful use of acetaminophen and prompt treatment in case of emergency can help prevent a tragedy.

MORE ON THIS TOPIC

• Acetaminophen (Oral Route, Rectal Route)