Home Drug Guide Codeine Phosphate (combined with Acetaminophen and Aspirin)

Drug Guide

Generic Name

Codeine Phosphate (combined with Acetaminophen and Aspirin)

Brand Names Acetaminophen & Aspirin with Codeine No. 3, No. 4, No. 2, Codeine, Aspirin, Apap Formula No. 3, No. 4, No. 2

Classification

Therapeutic: Analgesic, Antipyretic

Pharmacological: Opioid analgesic, Non-opioid analgesic (acetaminophen and aspirin)

FDA Approved Indications

  • Moderate to severe pain relief

Mechanism of Action

Codeine is an opioid agonist that acts on the central nervous system to inhibit pain pathways. Acetaminophen reduces pain and fever by inhibiting prostaglandin synthesis in the CNS. Aspirin inhibits cyclooxygenase enzymes (COX-1 and COX-2), decreasing prostaglandin synthesis, leading to analgesic, anti-inflammatory, and antipyretic effects.

Dosage and Administration

Adult: As prescribed, typically 15-60 mg of codeine with acetaminophen and aspirin every 4-6 hours, not exceeding 4 grams of acetaminophen daily.

Pediatric: Use with caution; generally not recommended for children under 12 years. Dose must be carefully calculated based on weight and age.

Geriatric: Start at lower end of dosing; assess renal and hepatic function.

Renal Impairment: Adjust dose; avoid if severe impairment.

Hepatic Impairment: Use with caution; may require dose adjustment.

Pharmacokinetics

Absorption: Well absorbed from gastrointestinal tract.

Distribution: Widely distributed; crosses blood-brain barrier and placental barrier.

Metabolism: Metabolized in the liver mainly via conjugation and CYP2D6 pathway for codeine to morphine.

Excretion: Excreted primarily via urine.

Half Life: Approximately 3-4 hours for codeine; varies based on individual metabolism.

Contraindications

  • Hypersensitivity to aspirin, acetaminophen, or codeine.
  • History of asthma or allergic reactions to NSAIDs or opioids.
  • Children under 12 years.
  • Use in elderly with caution.

Precautions

  • Risk of respiratory depression, especially in children, elderly, or those with impaired respiration.
  • Risk of hepatotoxicity (acetaminophen).
  • Gastrointestinal bleeding risk with aspirin.
  • Potential for addiction, abuse, and misuse of opioids.

Adverse Reactions - Common

  • Drowsiness, dizziness (Common)
  • Nausea, vomiting (Common)
  • Constipation (Common)

Adverse Reactions - Serious

  • Respiratory depression (Rare)
  • Hepatotoxicity (acetaminophen overdose) (Uncommon)
  • Gastrointestinal bleeding (aspirin) (Uncommon)
  • Allergic reactions including rash, anaphylaxis (Rare)

Drug-Drug Interactions

  • Warfarin, increasing bleeding risk; other CNS depressants; CYP2D6 inhibitors or inducers affecting codeine metabolism

Drug-Food Interactions

  • Alcohol increases risk of liver toxicity and CNS depression.

Drug-Herb Interactions

  • St. John’s Wort, may affect metabolism of codeine.

Nursing Implications

Assessment: Monitor pain relief effectiveness, respiratory status, liver function, bleeding tendency.

Diagnoses:

  • Pain, Acute
  • Risk for Respiratory Depression
  • Risk for Bleeding

Implementation: Administer with food or milk to decrease gastrointestinal upset. Monitor for signs of addiction or overdose.

Evaluation: Assess pain relief; monitor for adverse reactions; evaluate hepatic function if used long-term.

Patient/Family Teaching

  • Do not operate machinery or drive until response is known.
  • Avoid alcohol and other CNS depressants.
  • Report signs of allergic reactions, respiratory difficulty, or liver problems.
  • Follow dosing instructions carefully, especially in children and elderly.

Special Considerations

Black Box Warnings:

  • Risk of opioid addiction, abuse, and misuse; respiratory depression.

Genetic Factors: CYP2D6 ultra-rapid metabolizers may experience increased effects and toxicity.

Lab Test Interference: Potential for elevated liver enzymes with prolonged use.

Overdose Management

Signs/Symptoms: Respiratory depression, extreme drowsiness, confusion, nausea, vomiting, hypotension, cyanosis.

Treatment: Administer naloxone for opioid overdose; supportive measures including ventilatory support, activated charcoal if recent ingestion, and symptomatic management.

Storage and Handling

Storage: Store at room temperature, away from moisture, heat, and light.

Stability: Stable under recommended storage conditions.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.