Acetaminophen 500mg E/s Tablets

Acetaminophen (paracetamol) is thought to produce analgesia by inhibiting prostaglandin synthesis primarily in the central nervous system (CNS) and to a lesser extent peripherally. It may selectively inhibit cyclooxygenase (COX) enzymes, particularly COX-2 and possibly COX-3 (if it exists), in the brain and spinal cord. Its antipyretic effect is due to direct action on the hypothalamic heat-regulating center, leading to peripheral vasodilation and increased sweating.

Urgent Side Effects: Seek Medical Help Immediately

Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention right away:

Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of liver problems, including:
+ Dark urine
+ Tiredness
+ Decreased appetite
+ Upset stomach or stomach pain
+ Light-colored stools
+ Vomiting
+ Yellow skin or eyes
Urination problems, such as:
+ Inability to pass urine
+ Changes in urine output
Severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis), characterized by:
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Red or irritated eyes
+ Sores in the mouth, throat, nose, or eyes

Other Possible Side Effects

Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:

Upset stomach or vomiting
Trouble sleeping
Headache
Constipation

This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Taking This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following:

Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have liver disease, as this may affect the safety and efficacy of the medication.

This list is not exhaustive, and it is crucial to discuss all your health conditions and medications with your doctor. Please provide your doctor and pharmacist with a comprehensive list of:

All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
* Your health problems, including any medical conditions or diseases

To ensure your safety, do not start, stop, or change the dose of any medication without first consulting your doctor. It is vital to verify that it is safe to take this medication with all your other drugs and health conditions.

It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.

To avoid potential liver problems, be cautious not to take other products that contain acetaminophen. Carefully check the labels of all medications and supplements to ensure you are not exceeding the recommended daily dose of acetaminophen.

Follow the dosage instructions precisely, and do not exceed the maximum daily dose of acetaminophen as directed. The recommended daily dose can vary, but it should not exceed 4,000 milligrams (mg) unless specified by your doctor. However, certain individuals, such as those with liver problems or children, may require a lower dose. If you are unsure about the appropriate dose for your specific situation, consult your doctor or pharmacist. If you accidentally take too much acetaminophen in a day, contact your doctor immediately, even if you do not experience any symptoms.

Before consuming alcohol, discuss the potential risks with your doctor. Additionally, this medication may interfere with certain laboratory tests, so it is crucial to inform all your healthcare providers and laboratory personnel that you are taking this drug.

When administering this medication to children, note that different brands may have varying dosage recommendations. Therefore, consult your doctor before giving this medication to a child to ensure the correct dose is used.

If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. It is necessary to discuss the potential benefits and risks of taking this medication to both you and your baby.

• Not typically contraindicated with other drugs, but caution with other acetaminophen-containing products.

• Alcohol (chronic heavy use increases risk of hepatotoxicity)
• Warfarin (increased INR and bleeding risk with chronic, high-dose acetaminophen)
• Isoniazid (increased risk of hepatotoxicity)
• Phenytoin, Carbamazepine, Phenobarbital, Rifampin (inducers of CYP2E1, increasing NAPQI formation and hepatotoxicity risk)

• Cholestyramine (reduces acetaminophen absorption if given concurrently)
• Lamotrigine (may reduce lamotrigine levels)
• Zidovudine (may increase zidovudine levels and toxicity)

• Not typically associated with minor interactions of clinical significance.

• Signs of liver damage (e.g., yellowing of skin/eyes, dark urine, abdominal pain, nausea, vomiting, unusual tiredness)
• Signs of allergic reaction (e.g., rash, itching, swelling, severe dizziness, trouble breathing)
• Signs of gastrointestinal bleeding (e.g., black, tarry stools; coffee-ground vomit) - less common with acetaminophen than NSAIDs, but still possible with chronic use or in susceptible individuals.
• Signs of serious skin reactions (e.g., blistering, peeling skin, red or purple rash spreading and causing blistering and peeling)

Acetaminophen is generally considered the analgesic/antipyretic of choice during pregnancy when medically indicated, at the lowest effective dose for the shortest duration. However, recent observational studies have raised concerns about potential associations with neurodevelopmental disorders (e.g., ADHD, autism) in children exposed prenatally, particularly with prolonged or high-dose use. The clinical significance of these findings is still under investigation, and professional bodies recommend cautious use.

Acetaminophen is considered compatible with breastfeeding. It is excreted into breast milk in small amounts, but infant exposure is low and adverse effects are not expected at recommended maternal doses. It is generally considered the preferred analgesic/antipyretic for breastfeeding mothers.

Dosing must be strictly weight-based to avoid overdose. Always use appropriate formulations (e.g., liquid for infants/young children) and measuring devices. Avoid combination products containing acetaminophen if the child is already receiving single-ingredient acetaminophen.

No specific dose adjustment is typically required based on age alone. However, elderly patients may have reduced renal or hepatic function, or be on multiple medications, increasing the risk of adverse effects or drug interactions. Use with caution and monitor for signs of toxicity.

• Acetaminophen is NOT an anti-inflammatory drug like NSAIDs; it primarily provides pain relief and fever reduction.
• The most critical aspect of acetaminophen safety is avoiding accidental overdose, often due to taking multiple products containing acetaminophen (e.g., cold/flu remedies, pain relievers). Always check active ingredients.
• N-acetylcysteine (NAC) is the antidote for acetaminophen overdose and is most effective when administered within 8 hours of ingestion.
• Patients with chronic alcohol use, malnutrition, or pre-existing liver disease are at higher risk for acetaminophen-induced hepatotoxicity, even at therapeutic doses.
• Educate patients on the maximum daily dose and the importance of not exceeding it.

• Nonsteroidal Anti-inflammatory Drugs (NSAIDs) like Ibuprofen, Naproxen (for pain and fever, with anti-inflammatory effects)
• Aspirin (for pain, fever, and anti-inflammatory effects, but with different side effect profile)
• Opioid analgesics (for moderate to severe pain, with higher risk of side effects and dependence)
• Topical analgesics (e.g., lidocaine patches, capsaicin cream for localized pain)

If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure your safety, never share your medication with others or take someone else's medication. It's also important to note that some medications may come with a separate patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it occurred.