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Apadaz Side Effects

Generic name: acetaminophen / benzhydrocodone

Medically reviewed by Last updated on May 5, 2023.

Note: This document contains side effect information about acetaminophen / benzhydrocodone. Some dosage forms listed on this page may not apply to the brand name Apadaz.

Applies to acetaminophen / benzhydrocodone: oral tablet.


Oral route (Tablet)

Benzhydrocodone/acetaminophen exposes 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 benzhydrocodone/acetaminophen, and monitor all patients regularly for the development of these behaviors and conditions.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 Risk Evaluation and Mitigation Strategy (REMS) for these products.Serious, life-threatening, or fatal respiratory depression may occur with use of benzhydrocodone/acetaminophen. Monitor for respiratory depression, especially during initiation of benzhydrocodone/acetaminophen or following a dose increase.Accidental ingestion of even one dose of benzhydrocodone/acetaminophen, especially by children can result in a fatal overdose of hydrocodone.Prolonged use of benzhydrocodone/acetaminophen 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 prolonged opioid use is required in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available.The concomitant use of benzhydrocodone/acetaminophen with all cytochrome P450 3A4 inhibitors may result in an increase in hydrocodone plasma concentrations, which could increase or prolong adverse reactions and may cause potentially fatal respiratory depression. In addition, discontinuation of a concomitantly used cytochrome P450 3A4 inducer may result in an increase in hydrocodone plasma concentration. Monitor patients receiving benzhydrocodone/acetaminophen and any CYP3A4 inhibitor or inducer.This product contains acetaminophen. 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 mg/day, and often involve more than one acetaminophen-containing product.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 benzhydrocodone/acetaminophen and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required. Follow patients for signs and symptoms of respiratory depression and sedation.

Serious side effects of Apadaz

Along with its needed effects, acetaminophen / benzhydrocodone 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 / benzhydrocodone:

Less common

  • Blurred vision
  • confusion
  • difficult or labored breathing
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • excess air or gas in the stomach or bowels
  • feeling of warmth
  • full or bloated feeling
  • passing gas
  • pressure in the stomach
  • redness of the face, neck, arms, and occasionally, upper chest
  • shakiness in the legs, arms, hands, or feet
  • stomach pain
  • sweating
  • swelling of the stomach area
  • tightness in the chest
  • trembling or shaking of the hands or feet
  • unusual tiredness or weakness


  • Agitation
  • chest discomfort
  • fainting
  • false or unusual sense of well-being
  • heartburn
  • vomiting
  • vomiting of blood

Incidence not known

  • Cough
  • darkening of the skin
  • diarrhea
  • difficulty swallowing
  • discouragement
  • dizziness
  • fast heartbeat
  • feeling sad or empty
  • fever
  • hives, itching, skin rash
  • irritability
  • loss of appetite
  • loss of interest or pleasure
  • nausea
  • overactive reflexes
  • poor coordination
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • restlessness
  • shivering
  • talking or acting with excitement you cannot control
  • trembling or shaking
  • trouble concentrating
  • trouble sleeping
  • twitching

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

Symptoms of overdose

  • Black, tarry stools
  • chills
  • cold, clammy skin
  • dark urine
  • decreased awareness or responsiveness
  • headache
  • pale or blue lips, fingernails, or skin
  • severe sleepiness
  • unpleasant breath odor
  • yellow eyes or skin

Other side effects of Apadaz

Some side effects of acetaminophen / benzhydrocodone 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

Less common

  • Lack or loss of strength


  • Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • diarrhea
  • itching of the eye
  • nightmare
  • runny nose
  • sneezing
  • stuffy nose

For Healthcare Professionals

Applies to acetaminophen / benzhydrocodone: oral tablet.


The most commonly reported adverse reactions have included nausea, somnolence, vomiting, constipation, pruritus, dizziness, and headache.[Ref]


Frequency not reported: Rhinitis


Frequency not reported: Respiratory depression

Rhinitis has been reported in less than 1% of patients.


Serious skin reactions such as acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson Syndrome (SJS), and toxic epidermal necrolysis (TEN) have been associated with acetaminophen use.

Common (1% to 10%): Pruritus


Rare (less than 0.1%): Serious skin reactions



Frequency not reported: Hepatotoxicity


Very common (10% or more): Nausea (21.5%), vomiting (13%), constipation (12%)

Common (1% to 10%): Abdominal distension, abdominal pain, flatulence

Frequency not reported: Diarrhea, gastroesophageal reflux disease, hematemesis

Diarrhea, gastroesophageal reflux disease, and hematemesis have been reported in less than 1% of patients.


Frequency not reported: Agitation, euphoric mood, nightmare

Agitation, euphoric mood, and nightmare have been reported in less than 1% of patients.

Nervous system

Very common (10% or more): Somnolence (18.5%)

Common (1% to 10%): Dizziness, headache, asthenia, presyncope, tremor

Frequency not reported: Syncope, hypoesthesia

Postmarketing reports: Serotonin syndrome

Syncope and hypoesthesia have been reported in less than 1% of patients. Cases of serotonin syndrome have been reported during concomitant use of opioids with serotonergic drugs.


Common (1% to 10%): Hypotension, hot flush

Frequency not reported: Chest discomfort

Chest discomfort has been reported in less than 1% of patients.


Frequency not reported: Eye pruritus

Eye pruritus has been reported in less than 1% of patients.



Postmarketing reports: Adrenal insufficiency, androgen deficiency

Cases of adrenal insufficiency and androgen deficiency have been reported with opioid use, more often following greater chronic use.


Postmarketing reports: Anaphylaxis

Anaphylaxis has been reported with ingredients contained in this product.

Frequently asked questions


1. "Product Information. Apadaz (acetaminophen-benzhydrocodone)." KemPharm, Inc (2018):

Further information

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.