Naproxen, sold under brand names like Aleve and Naprosyn, is a nonsteroidal anti-inflammatory drug (NSAID) widely used to manage pain, inflammation, and fever. It is possible to take more than the recommended amount, which can lead to a serious medical event known as an overdose. An overdose occurs when the amount ingested overwhelms the body’s ability to safely process the drug, resulting in toxic effects. Recognizing the difference between a therapeutic dose and a toxic dose is fundamental for safe medication use.
Understanding Therapeutic and Toxic Doses
Naproxen works by inhibiting cyclooxygenase (COX) enzymes, which produce prostaglandins that trigger pain and inflammation. The therapeutic dose aims to reduce these inflammatory mediators without causing harm to the body’s protective systems. For over-the-counter naproxen, the typical recommended daily limit for adults is 600 to 660 milligrams, while prescription dosages can be higher.
The acute maximum daily dose for prescription naproxen can be up to 1500 milligrams, but this is usually only recommended for limited periods. The long-term maximum is around 1000 milligrams daily. Toxicity becomes a serious concern when doses significantly exceed these maximums, though the exact toxic dose varies widely based on individual health factors. Excessive amounts of naproxen disrupt normal bodily functions, especially in the gastrointestinal tract and kidneys.
Recognizing the Signs of Naproxen Overdose
The signs of an acute naproxen overdose range from milder symptoms to severe, life-threatening complications. Initial, common signs often involve the gastrointestinal system, including severe nausea, vomiting, stomach pain, and heartburn. Drowsiness, dizziness, and mild confusion are also frequently reported in less severe ingestions.
As the drug concentration rises to toxic levels, more serious signs emerge, reflecting damage to various organ systems. Neurological symptoms can progress to severe headache, agitation, unsteadiness, or ringing in the ears (tinnitus). Large overdoses can lead to kidney failure, resulting in decreased or absent urination, and a buildup of acid in the blood (metabolic acidosis). The risk of internal bleeding, particularly in the stomach and intestines, increases significantly, sometimes evidenced by bloody or black, tarry stools. In the most severe cases, an overdose can cause seizures, severely altered mental status, and potentially coma.
Immediate Steps If Overdose is Suspected
A suspected naproxen overdose requires immediate action, as the toxic effects can rapidly worsen. If the person is unconscious, having a seizure, or experiencing difficulty breathing, call the local emergency number, such as 911, right away. For any suspected overdose, regardless of symptom severity, the national toll-free Poison Help hotline (1-800-222-1222) should be contacted immediately.
When speaking with emergency services or Poison Control, be prepared to provide specific details to guide the medical response. This information should include the person’s age, weight, and existing conditions, the name and strength of the product taken, the approximate time of ingestion, and the total amount swallowed. Medical intervention often focuses on supportive care, meaning treating the symptoms as they arise and monitoring vital signs. If the ingestion was recent and the patient has a protected airway, activated charcoal may be administered in the emergency room to help bind the drug and reduce its absorption.
Factors Increasing Overdose Risk
Certain pre-existing health conditions and drug combinations can significantly lower the threshold for naproxen toxicity. An overdose can occur at a dose that might be safe for a healthy person. Individuals with impaired kidney function, liver disease, or chronic heart failure are at greater risk because their bodies cannot efficiently process and eliminate the drug. Naproxen can also directly worsen these conditions by reducing blood flow to the kidneys and causing fluid retention.
Combining naproxen with other substances can amplify the risk of adverse effects, particularly internal bleeding. Taking naproxen alongside blood thinners, such as warfarin, or other NSAIDs, including aspirin, increases the risk of severe gastrointestinal bleeding due to the cumulative anti-platelet effect. Co-ingestion with alcohol significantly elevates the risk of stomach irritation and bleeding. Furthermore, certain medications like diuretics, SSRIs, and lithium can interact with naproxen, increasing the likelihood of kidney injury or causing drug levels to become dangerously high.