Nurses Compass
Drug Guide
Acetaminophen and Ibuprofen
Classification
Therapeutic: Analgesic, Antipyretic
Pharmacological: Acetaminophen: Central analgesic and antipyretic; Ibuprofen: Nonsteroidal Anti-Inflammatory Drug (NSAID)
FDA Approved Indications
- Relief of mild to moderate pain
- Fever reduction
Mechanism of Action
Acetaminophen acts centrally in the brain to inhibit prostaglandin synthesis, reducing pain and fever. Ibuprofen inhibits cyclooxygenase (COX-1 and COX-2) enzymes, decreasing prostaglandin synthesis involved in inflammation, pain, and fever.
Dosage and Administration
Adult: Dose varies; typically 325-650 mg every 4-6 hours as needed, not exceeding 3,000-4,000 mg per day.
Pediatric: Dose based on weight; usually 10-15 mg/kg every 4-6 hours, not exceeding 5 doses in 24 hours.
Geriatric: Adjust dose if renal or hepatic impairment present; cautious use due to increased bleeding risk with NSAIDs.
Renal Impairment: Limit NSAID use; careful monitoring suggested.
Hepatic Impairment: Avoid or limit use of acetaminophen; monitor liver function.
Pharmacokinetics
Absorption: Rapid absorption from gastrointestinal tract.
Distribution: Widely distributed; crosses blood-brain barrier.
Metabolism: Acetaminophen metabolized in liver via conjugation; Ibuprofen metabolized mainly in liver via hydroxylation.
Excretion: Renal excretion of metabolites.
Half Life: Acetaminophen: about 2-3 hours; Ibuprofen: about 2 hours.
Contraindications
- Allergy to acetaminophen or ibuprofen
- Severe hepatic impairment (acetaminophen)
- History of NSAID-induced asthma, urticaria, or allergic reactions
Precautions
- Use cautiously in patients with bleeding disorders, renal impairment, gastric ulcers, or cardiovascular disease.
Adverse Reactions - Common
- Nausea, vomiting, stomach upset (Common)
- Rash, allergic reactions (Less common)
Adverse Reactions - Serious
- Hepatotoxicity (acetaminophen overdose) (Rare but serious)
- Gastrointestinal bleeding, ulceration (NSAID related) (Less common)
- Anaphylaxis (Rare)
Drug-Drug Interactions
- Warfarin, other anticoagulants, other NSAIDs, corticosteroids
Drug-Food Interactions
- Alcohol (increases risk of liver toxicity and gastrointestinal bleeding)
Drug-Herb Interactions
- Ginger, ginseng (may increase bleeding risk)
Nursing Implications
Assessment: Monitor for pain relief, fever, signs of gastrointestinal bleeding, liver function, and renal function.
Diagnoses:
- Acute pain
- Risk for bleeding
- Impaired liver function
Implementation: Administer with food or milk to decrease gastrointestinal irritation. Check hepatic and renal function as needed.
Evaluation: Assess pain relief, temperature reduction, and monitor for adverse effects.
Patient/Family Teaching
- Do not exceed recommended dose.
- Take with food or milk if gastrointestinal upset occurs.
- Avoid alcohol while taking.
- Report signs of allergic reactions, gastrointestinal bleeding, or liver problems.
Special Considerations
Black Box Warnings:
- Risk of serious liver injury with high doses or prolonged use of acetaminophen.
- Increased risk of cardiovascular events and gastrointestinal bleeding with NSAIDs.
Genetic Factors: Genetic variability may influence metabolism, especially for acetaminophen hepatotoxicity.
Lab Test Interference: May interfere with certain liver function tests.
Overdose Management
Signs/Symptoms: Nausea, vomiting, sweating, pallor, malaise, hepatic failure in severe cases.
Treatment: Administer activated charcoal if ingestion was recent; acetylcysteine (NAC) for acetaminophen overdose; supportive care, monitor liver function.
Storage and Handling
Storage: Store at room temperature, away from moisture and heat.
Stability: Stable under recommended storage conditions.