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Phenaphen With Codeine Side Effects

Generic name: acetaminophen / codeine

Medically reviewed by Drugs.com. Last updated on Aug 5, 2023.

Note: This document provides detailed information about Phenaphen with Codeine Side Effects associated with acetaminophen / codeine. Some dosage forms listed on this page may not apply specifically to the brand name Phenaphen with Codeine.

Applies to acetaminophen / codeine: oral elixir, oral solution, oral tablet.

Important warnings This medicine can cause some serious health issues

Oral route (tablet)

Addiction, Abuse, and Misuse

Acetaminophen and codeine phosphate tablets expose patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death.

Assess each patient's risk prior to prescribing acetaminophen and codeine phosphate tablets, and monitor all patients regularly for the development of these behaviors or conditions.

Life-Threatening Respiratory Depression

Serious, life-threatening, or fatal respiratory depression may occur with use of acetaminophen and codeine phosphate tablets.

Monitor for respiratory depression, especially during initiation of acetaminophen and codeine phosphate tablets or following a dose increase.

Opioid Analgesic Risk Evaluation and Mitigation Strategy (REMS)

: To ensure that the benefits of opioid analgesics outweigh the risks of addiction, abuse, and misuse, the Food and Drug Administration (FDA) has required a REMS for these products.

Under the requirements of the REMS, drug companies with approved opioid analgesic products must make REMS-compliant education programs available to healthcare providers.

Healthcare providers are strongly encouraged to; complete a REMS-compliant education program, counsel patients and/or their caregivers, with every prescription, on safe use, serious risks, storage, and disposal of these products, emphasize to patients and their caregivers the importance of reading the Medication Guide every time it is provided by their pharmacist, and consider other tools to improve patient, household, and community safety.

Accidental Ingestion

Accidental ingestion of acetaminophen and codeine phosphate tablets, especially by children, can result in a fatal overdose of acetaminophen and codeine phosphate tablets.

Ultra-Rapid Metabolism of Codeine and Other Risk Factors for Life-Threatening Respiratory Depression in Children

Life-threatening respiratory depression and death have occurred in children who received codeine.

Most of the reported cases occurred following tonsillectomy and/or adenoidectomy and many of the children had evidence of being ultra-rapid metabolizers of codeine due to CYP2D6 polymorphism.

Acetaminophen and codeine phosphate tablets are contraindicated in children younger than 12 years of age and in children younger than 18 years of age following tonsillectomy and/or adenoidectomy.

Avoid the use of acetaminophen and codeine phosphate tablets in adolescents 12 to 18 years of age who have other risk factors that may increase their sensitivity to the respiratory depressant effects of codeine.

Neonatal Opioid Withdrawal Syndrome

Prolonged use of acetaminophen and codeine phosphate tablets during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated, and requires management according to protocols developed by neonatology experts.

If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available.Interactions with Drugs Affecting Cytochrome P450 Isoenzymes: The effects of concomitant use or discontinuation of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with codeine are complex.

Use of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with acetaminophen with codeine requires careful consideration of the effects on the parent drug, codeine, and the active metabolite, morphine.Hepatotoxicity: Acetaminophen has been associated with cases of acute liver failure, at times resulting in liver transplant and death.

Most of the cases of liver injury are associated with the use of acetaminophen at doses that exceed 4000 milligrams per day, and often involve more than one acetaminophen-containing product.

Risks from Concomitant Use with Benzodiazepines or Other CNS Depressants

Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death.

Reserve concomitant prescribing of acetaminophen and codeine phosphate tablets and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate.

Follow patients for signs and symptoms of respiratory depression and sedation.

Oral route (solution)

of Medication Errors: Ensure accuracy when prescribing, dispensing, and administering acetaminophen and codeine phosphate oral solution.

Dosing errors due to confusion between mg and mL, and other codeine containing oral products of different concentrations can result in accidental overdose and death.

Addiction, Abuse, and Misuse

Acetaminophen and codeine phosphate oral solution expose patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death.

Assess each patient's risk prior to prescribing acetaminophen and codeine phosphate oral solution, and monitor all patients regularly for the development of these behaviors or conditions.

Life-Threatening Respiratory Depression

Serious, life-threatening, or fatal respiratory depression may occur with use of acetaminophen and codeine phosphate oral solution.

Monitor for respiratory depression, especially during initiation of acetaminophen and codeine phosphate oral solution or following a dose increase.

Opioid Analgesic Risk Evaluation and Mitigation Strategy (REMS)

: To ensure that the benefits of opioid analgesics outweigh the risks of addiction, abuse, and misuse, the Food and Drug Administration (FDA) has required a REMS for these products.

Under the requirements of the REMS, drug companies with approved opioid analgesic products must make REMS-compliant education programs available to healthcare providers.

Healthcare providers are strongly encouraged to; complete a REMS-compliant education program, counsel patients and/or their caregivers, with every prescription, on safe use, serious risks, storage, and disposal of these products, emphasize to patients and their caregivers the importance of reading the Medication Guide every time it is provided by their pharmacist, and consider other tools to improve patient, household, and community safety.

Accidental Ingestion

Accidental ingestion of acetaminophen and codeine phosphate oral solution, especially by children, can result in a fatal overdose of acetaminophen and codeine phosphate oral solution.

Ultra-Rapid Metabolism of Codeine and Other Risk Factors for Life-Threatening Respiratory Depression in Children

Life-threatening respiratory depression and death have occurred in children who received codeine.

Most of the reported cases occurred following tonsillectomy and/or adenoidectomy and many of the children had evidence of being ultra-rapid metabolizers of codeine due to CYP2D6 polymorphism.

Acetaminophen and codeine phosphate oral solution are contraindicated in children younger than 12 years of age and in children younger than 18 years of age following tonsillectomy and/or adenoidectomy.

Avoid the use of acetaminophen and codeine phosphate oral solution in adolescents 12 to 18 years of age who have other risk factors that may increase their sensitivity to the respiratory depressant effects of codeine.

Neonatal Opioid Withdrawal Syndrome

Prolonged use of acetaminophen and codeine phosphate oral solution during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated, and requires management according to protocols developed by neonatology experts.

If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available.Interactions with Drugs Affecting Cytochrome P450 Isoenzymes: The effects of concomitant use or discontinuation of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with codeine are complex.

Use of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with acetaminophen with codeine oral solution requires careful consideration of the effects on the parent drug, codeine, and the active metabolite, morphine.Hepatotoxicity: Acetaminophen has been associated with cases of acute liver failure, at times resulting in liver transplant and death.

Most of the cases of liver injury are associated with the use of acetaminophen at doses that exceed 4000 milligrams per day, and often involve more than one acetaminophen-containing product.

Risks from Concomitant Use with Benzodiazepines or Other CNS Depressants

Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death.

Reserve concomitant prescribing of acetaminophen and codeine phosphate oral solution and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate.

Follow patients for signs and symptoms of respiratory depression and sedation.

Serious side effects

Along with its needed effects, acetaminophen / codeine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking acetaminophen / codeine:

More common side effects

  • difficult or trouble breathing
  • irregular, fast or slow, or shallow breathing
  • pale or blue lips, fingernails, or skin

Incidence not known

  • black, tarry stools
  • bleeding gums
  • blood in the urine or stools
  • cough
  • difficulty with swallowing
  • dizziness
  • fast heartbeat
  • fever with or without chills
  • general feeling of tiredness or weakness
  • hives, itching, skin rash
  • hoarseness
  • lower back or side pain
  • painful or difficult urination
  • pinpoint red spots on the skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • tightness in the chest
  • unusual bleeding or bruising
  • unusual tiredness or weakness

Get emergency help immediately if any of the following symptoms of overdose occur while taking acetaminophen / codeine:

Symptoms of overdose

Other side effects

Some side effects of acetaminophen / codeine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common side effects

  • drowsiness
  • lightheadedness
  • relaxed and calm feeling
  • sleepiness

Incidence not known

  • difficulty having a bowel movement
  • false or unusual sense of well-being

Managing side effects (general information)

For healthcare professionals

Applies to acetaminophen / codeine: oral capsule, oral liquid, oral suspension, oral tablet.

General adverse events

The most frequently observed adverse reactions include drowsiness, lightheadedness, dizziness, sedation, shortness of breath, nausea, and vomiting.[Ref]

Nervous system

Acetaminophen-codeine:

Acetaminophen:

Opioids:

Gastrointestinal

Acetaminophen-codeine:

Acetaminophen:

Opioids:

Hepatic

Acetaminophen:

Psychiatric

Acetaminophen-codeine:

Opioid:

Renal

Acetaminophen-codeine:

Acetaminophen:

Hypersensitivity

Acetaminophen-codeine:

Acetaminophen:

Opioids:

Cardiovascular

Acetaminophen:

Opioids:

Genitourinary

Acetaminophen-codeine:

Opioids:

Hematologic

Acetaminophen-codeine:

Acetaminophen:

Dermatologic

Acetaminophen-codeine:

Acetaminophen:

Respiratory

Acetaminophen-codeine:

Acetaminophen:

Codeine:

In patients with a tendency of analgesic asthma acetaminophen-use has triggered bronchospasms.[Ref]

Ocular

Opioids:

References

1. Cerner Multum, Inc. "UK Summary of Product Characteristics."

2. Cerner Multum, Inc. "Australian Product Information."

3. (2015) "Product Information. Acetaminophen-Codeine Phosphate (acetaminophen-codeine)." Qualitest Products Inc

Further information

Phenaphen with Codeine side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

Medical Disclaimer