Acetaminophen is a common over-the-counter medication used to reduce fever and alleviate minor to moderate pain. In many households, it is the go-to medication for minor complaints including headaches, backaches, menstrual cramps, and general flu symptoms. While acetaminophen, also known as paracetamol outside the U.S., is a safe and effective medication when used correctly, it’s important to be aware of the potential dangers of overuse, especially when it’s used in combination with other drugs. Workers’ Compensation patients may turn to acetaminophen for pain relief but may not be aware of the risks. As this article will discuss, while generally safe, overdosing on acetaminophen can cause severe liver damage and lead to increased workers’ compensation costs for treatment.
Causes of Acetaminophen Overdose
While acetaminophen is generally safe and used by many adults and children successfully to alleviate pain and fever, there are risks of overdose.
Common reasons for an accidental overdose include:[1]
- Taking the next dose too soon
- Using multiple medicines that contain acetaminophen at the same time
- Taking too much at one time
Check the Label for Frequency Directions
It is always recommended that patients read the ingredients and directions for dosing on all over-the-counter (OTC) and prescription medications. Close attention should be paid to the suggested dosage and how often the medication should be taken. The amount and frequency should never be exceeded without consulting the patient’s healthcare provider.
Acetaminophen and Drug Interactions
Acetaminophen is often found in combination with other medications, including OTC cold, flu, and sleep aids.[2] In fact, there are more than 600 medications – both prescription and OTC – that contain acetaminophen. Patients need to be cautious not to exceed the daily limit and may not always be aware that they are doubling up when taking several medications at a time.
Acetaminophen can also interact with certain medications. For example, using acetaminophen together with isoniazid, a drug used to treat tuberculosis, may alter the effects of acetaminophen and cause serious side effects that may affect the liver. Other known drugs that can interact with acetaminophen include warfarin, a common anticoagulant, and certain seizure medications. Healthcare providers should check for acetaminophen interactions and advise patients on safe alternatives.
Safe Dosages and Pharmacy Alerts
The majority of acetaminophen overdoses occur when the drug is taken in amounts larger than recommended.[3] The U.S. Food and Drug Administration (FDA) recommends a maximum daily dose of 4,000 milligrams (mg) for adults. However, some healthcare providers suggest a lower maximum daily dose of 3,000 mg. The maximum daily dose for children depends on the child’s weight.
Pharmacies bear a significant burden in protecting consumers from acetaminophen overdose and drug interactions. Unfortunately, pharmacy dispensing systems can only track acetaminophen doses for dispensed medications, not OTC drugs, and only when the same pharmacy or pharmacy chain is used for the purchase. Consumers who use multiple pharmacies and who purchase OTC medications will not be alerted in a high dose situation.
Symptoms of Acetaminophen Overdose
Symptoms of an acetaminophen overdose may not appear immediately, and some individuals may remain symptom-free for up to 24 hours after taking a toxic dose.[4] But in most cases, early signs and symptoms of overdose appear sooner and may resemble those of the flu.[5]
Common symptoms during each stage of an acetaminophen overdose include:[6]
- First 24 hours: Loss of appetite, nausea, vomiting, stomach pain, paleness, tiredness, and sweating
- 24 to 72 hours after the overdose: Pain in the upper right side of the abdomen, dark urine, and yellowing of the skin and the whites of the eyes
- 72 to 96 hours after the overdose: Blood in urine, fever, lightheadedness, fast breathing, extreme weakness, blurred vision, confusion, and even coma
The antidote to acetaminophen overdose is N-acetylcysteine (NAC). It is most effective when given within eight hours of ingesting acetaminophen, so prompt treatment is crucial.[7] If overuse is suspected, patients should seek immediate help from a doctor, a poison control center, or emergency medical services.
Acetaminophen and Liver Damage
The primary danger of acetaminophen overuse is liver damage. Since acetaminophen is primarily metabolized by the liver, too much can overwhelm the way the liver normally functions.[8] If the liver is already compromised due to infection, alcohol abuse, or other illness, a person may be more susceptible to liver damage. Taking warfarin or consuming three or more alcoholic beverages a day can also increase the risk of liver damage. In severe cases, an overdose of acetaminophen can cause liver failure or even death.
What Does This Mean for Workers’ Compensation?
In our recent article, Comorbidity and Aging, we looked at the impact that comorbidities in older workers can have on workers’ compensation claims. Unfortunately, workers’ compensation claims that carry comorbidities have been shown to be more serious and longer lasting – making them more expensive for payers. Therefore, a worker who already has liver damage is especially at risk for acetaminophen overuse. A combination of employee education and health screenings at work can mitigate the potential for acetaminophen overuse and further liver damage.
Liver damage, whether due to chronic conditions like cirrhosis, hepatitis, or other factors such as acetaminophen overuse, can negatively impact a person’s quality of life. Physical symptoms and mental and emotional impact can affect work productivity by contributing to absenteeism, low energy, and reduced mental acuity on the job. And, in the worst-case scenario, the estimated cost for a liver transplant as of 2020 was close to $900,000, including procurement, procedure, and aftercare.[9]
New Developments in Pain Relief
In another recent article, we discussed the national opioid crisis and new medications that offer pain relief without addiction. It’s been shown that acetaminophen and ibuprofen, when used together, can be as effective as many opioids.[10] These findings may increase the potential for higher doses of acetaminophen by patients. This in turn, should concern Workers’ Compensation payers – when patients use more acetaminophen for additional pain relief, there is an increased chance of unintentional overuse. Overuse leads to liver damage, which leads directly to hospitalizations and increased claim costs.
Conclusion
Acetaminophen is safe and effective when used as directed. However, acetaminophen is a common ingredient in many medications, and it’s possible to take too much without realizing it. It’s also possible to take too much without thinking of the risks. Even though it’s readily available, acetaminophen comes with serious safety warnings and risks. Workers’ Compensation patients suffering from all levels of pain should be alerted to the dangers of overuse. Workers’ Compensation payers who seek optimum recovery for their workers should educate their employees about correct and safe usage of acetaminophen as they strive to restore quality of life and achieve a successful return to the workforce.
Contact us if you have questions about acetaminophen overuse.
Footnotes:
[1] https://www.healthline.com/health/acetaminophen-overdose
[2] https://www.drugs.com/cg/acetaminophen-overdose.html
[3] https://www.healthline.com/health/acetaminophen-overdose
[4] https://www.webmd.com/a-to-z-guides/tylenol-acetaminophen-poisoning
[5] https://www.healthline.com/health/acetaminophen-overdose
[6] https://www.healthline.com/health/acetaminophen-overdose
[7] https://www.webmd.com/a-to-z-guides/tylenol-acetaminophen-poisoning
[8] https://www.webmd.com/a-to-z-guides/tylenol-acetaminophen-poisoning
[9] https://www.medicalnewstoday.com/articles/how-much-does-a-liver-cost
[10] https://www.aafp.org/pubs/afp/issues/2018/0301/p348.html