Acetaminophen is one of the most known and used medical substances, entering into the composition of numerous OTC (over-the-counter) products. Perhaps its popularity makes patients to often ignore its danger of overdose. Like any medical substance, acetaminophen can be extremely harmful to the body, under abusive dosages, and few people know that an acetaminophen overdose can cause hepatotoxicity (liver injury).

Acetaminophen has a weak analgesic action, preferred to treat fever, including young children, and to reduce symptoms of colds and flu. You can take acetaminophen when you have moderate pain such as headaches, back pain, menstrual or dental pain, if you suffer a sprain, a fracture or a dislocation.

Acetaminophen is available in various pharmaceutical forms (tablets, suppositories or drops) and does not require prescription. Experts say that you can use it either alone or in combination with other analgesics or anti-inflammatory.

Symptoms of an acetaminophen overdose

The toxic manifestations of an acetaminophen overdose are succeeding in four stages:

• - nausea, vomiting, loss of appetite, weakness - occur in the first 24 hours after ingestion and are often ignored;
• - elevated transaminases, 24-48 hours after ingestion, but in most cases the patient would not think to investigate through liver analysis, because during this time he seems healthy and feels quite well;
• - vomiting, jaundice, bleeding, confusion, lethargy or even coma - these manifestations appear within 3-4 days after ingestion and delineates the critical stage, in which death can occur due to hepatic necrosis, if the dose was too high or if there were other factors that favor the evolution of toxicity: early age, nutritional deficiencies, alcoholism, liver disease and concomitant treatment with isoniazid, rifampin, phenytoin, carbamazepine or phenobarbital.
• - remission stage - occurs only in patients who survived the third stage, 6 days after ingestion and is manifested by normalization of transaminases and improving strength.

 How to prevent an acetaminophen overdose?

Overdose is often a consequence of self-medication because the patient ignores the fact that acetaminophen is sold under various trade names, both simple and in combination with other substances. On the other hand, sometimes associates more products that all contain acetaminophen, leading to overdose, even if they meet the mode of administration for each product. To avoid acetaminophen overdose, always seek advice from a pharmacist regarding the association of OTC products and inform about the composition of each product purchased.

If fever does not respond to usual dose of acetaminophen, you can alternate (with your doctor’s permission) the administration of drugs containing ibuprofen, but in NO circumstances increase the dose of acetaminophen. This advice is especially addressed to mothers who use syrup or suppositories based on acetaminophen and sometimes are tempted to exceed the normal rate of administration. If fever does not respond to usual acetaminophen doses then exceeds the competence of pharmacist and (obviously) also patient, because many times can signal a severe disease with a rampant development, that need urgent medical attention.

Acetaminophen Overdose Treatment and Care

Due to the severity of acetaminophen overdose, patients should not try to treat themselves at home. After they realized that they exceeded the maximum permissible acetaminophen dosage are advised to present at the Emergency Room or call an ambulance, especially if occurring manifestations of respiratory distress. If the patient is conscious, is recommended to properly inform the hospital medical staff regarding the drugs that were administered, because acetaminophen interacts with many other substances and also the dosage (and therefore the number of pills) and the time that has elapsed since ingestion. Acetaminophen interacts with substances such as carbamazepine, isoniazid, rifampin and enhances the anticoagulant effect of warfarin.

Acetaminophen toxicity benefit from a specific antidote: acetylcysteine - a substance in the composition of many of expectorant drugs. It only antagonizes the toxic effects of acetaminophen, without reducing the therapeutic effects.

As an antidote, is useful only if the administration is (under medical supervision) soon after ingestion of acetaminophen overdose, either orally or intravenously - so it is absolutely necessary to seek medical attention. If the overdose was diagnosed immediately, may be useful: activated charcoal (a substance that absorbs poisons), emesis induction and gastric lavage.

Acetaminophen overdose: Five days treatment

Avoid taking acetaminophen for a period longer than five days, because of the risk to occur kidney or liver problems. In fact, is not indicated taking acetaminophen if you have hepatic or renal impairment and not administer in combination with other hepatotoxic drug.

Also, is good to know that you should not take a higher dosage of one gram (two tablets) two to three times a day. For children aged 3 to 12 years, is recommended a maximum dose of half a tablet, two to three times a day. For higher acetaminophen doses, the treatment must be done under medical supervision.

The maximum dose of acetaminophen, in adults, is generally four to six tablets per day. People with liver disease should avoid high doses of acetaminophen, overdose affecting the liver, even for those without major problems at this stage.

Acetaminophen overdose specialized treatment

Acetaminophen treatment established at the emergency room depends very much on pathology background of the patient but also other substances that could be administered together. If an acetaminophen overdose is suspected but the patient is asymptomatic, the first measures include:

• Gastric decontamination - is achieved by oral administration of activated charcoal (which has the capacity to absorb acetaminophen) if administered 1 hour after ingestion. Activated charcoal is indicated in very few cases because they rarely see the doctor in the first minutes after ingestion.
• Emptying the stomach has the same indications as activated charcoal administration. Gastric lavage is done to prevent and reduce the absorption of acetaminophen. Activated charcoal is recommended to patients who have ingested substances that may reduce gastric motility and emptying. Activated charcoal is contraindicated if there is an overdose of acid or alkaline substances, and his administration should be made with caution for alcoholic patients or having co-ingested lithium or iron salts.
• Administration of N-acetylcysteine - this is the antidote for acetaminophen overdose. It can be administered orally, through a nasogastric tube or intravenously. N-acetylcysteine ​​has a bad taste but can be managed with a fruit juice and is administered for 20-72 hours. Studies have shown that the substance is 100% hepatoprotective if administered within 8 hours after ingestion.

The most common side effects of N-acetylcysteine ​​include anaphylactoid reactions, usually manifested by skin rash, wheezing and hypotension. They are more common in patients treated with intravenous N-acetylcysteine, and the percentage of occurrence varies between 5-25% of patients. Reactions can sometimes be serious, especially to asthmatic patients.

The patient must be examined by a medical toxicologist especially if the situation became complicated and the acetaminophen overdose was combined with other toxic substances.

Acetaminophen overdose can endanger the lives of children

Acetaminophen is one of the most popular medication, both in adults and children when it comes to fever. An overdose in children is more common than you think therefore you must be extremely cautious with the administration of this drug. It is true that acetaminophen is found in any pharmacy and you do not need a prescription (OTC) to buy, but it is a drug that should not be taken only under certain conditions.

The World Health Organization (WHO) recommends acetaminophen use in children only when the body temperature is higher than 38.5 ˚ C. Fever is the body's way of fighting infection. The role of antipyretic drugs is not to normalize the temperature, but to lower it as necessary for your child to feel a little more comfortable, and the body can continue to fight against germs.

Pay attention before you administer acetaminophen to your baby

Drops for babies and those for older children have different amounts of acetaminophen. A drop of syrup for babies does not have the same amount of medicine as a drop of syrup for older children.

Respect the recommended dose. The proper acetaminophen dose for your child is based on weight, not age. Most syrup is accompanied by a measuring device to help you put the right amount. Avoid using spoons because not all have the same capacity.

Never be used if your children have already received other medicines containing acetaminophen. Do not associate with other medication unless directed by a doctor.

Always use only those medication produced especially for children. Those for adults may contain in a drop / spoon / tablet a higher concentration of active substance than others. So, buy only medication dedicated to children and never divide the adults dosage in halves, quarters, etc..

How to prevent an overdose in children

• - do not leave acetaminophen in places where children could reach and mistake medicines with candy or juice;
• - check the warranty term;
• - do not administrate more than one product containing acetaminophen;
• - do not repeat dosage too early: fever decreases on average one hour after the administration;
• - do not exceed the maximum allowed dose in 24 hours: usually, it may be repeated every four hours but not more than five times in 24 hours;

Advice for patients

To avoid acetaminophen overdose must take into account the following recommendations: always follow the mode of administration and never associate products that all contain acetaminophen. Have patience that the drug to manifest effect and do not increase the rate of administration. Do not ignore paleness, weakness and nausea, if they occur after administration of products that contain acetaminophen. Present yourself to the emergency room immediately if you detect possible acetaminophen overdose.