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Ultracet Side Effects

Generic name: acetaminophen / tramadol

Medically reviewed by Last updated on Feb 13, 2024.

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

Applies to acetaminophen / tramadol: oral tablet.


Oral route (Tablet)

Addiction, Abuse, and MisuseTraMADol hydrochloride/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 traMADol hydrochloride/acetaminophen, and monitor all patients regularly for the development of these behaviors or conditions.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 pharmacists, and consider other tools to improve patient, household, and community safety.Life-threatening Respiratory DepressionSerious, life-threatening, or fatal respiratory depression may occur with use of traMADol hydrochloride/acetaminophen. Monitor for respiratory depression, especially during initiation of traMADol hydrochloride/acetaminophen or following a dose increase.Accidental IngestionAccidental ingestion of even one dose of traMADol hydrochloride/acetaminophen, especially by children, can result in a fatal overdose of traMADol.Ultra-Rapid Metabolism of TraMADol and Other Risk Factors for Life-Threatening Respiratory Depression in ChildrenLife-threatening respiratory depression and death have occurred in children who received traMADol. Most of the reported cases occurred following tonsillectomy and/or adenoidectomy, and many of the children had evidence of being an ultra-rapid metabolizer of codeine due to a CYP2D6 polymorphism. TraMADol hydrochloride/acetaminophen 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 traMADol hydrochloride/acetaminophen 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 traMADol.Neonatal Opioid Withdrawal SyndromeProlonged use of traMADol hydrochloride/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 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 IsoenzymesThe effects of concomitant use or discontinuation of CYP3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with traMADol are complex. Use of CYP3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with traMADol hydrochloride requires careful consideration of the effects on the parent drug, traMADol, and the active metabolite, M1.HepatotoxicityTraMADol hydrochloride/acetaminophen contains traMADol hydrochloride and 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 per day, and often involve more than 1 acetaminophen-containing product.Risks from Concomitant Use with Benzodiazepines or Other CNS DepressantsConcomitant use of opioids with benzodiazepines or other CNS depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of traMADol hydrochloride 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 Ultracet

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


Incidence not known

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

Symptoms of overdose

Other side effects of Ultracet

Some side effects of acetaminophen / tramadol 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:

Less common


For Healthcare Professionals

Applies to acetaminophen / tramadol: oral tablet.


The most common adverse reactions include nausea, somnolence, and dizziness.[Ref]



Uncommon (0.1% to 1%): Increased transaminases, abnormal hepatic function


Frequency not reported: Acute liver failure


Frequency not reported: Hepatitis, liver failure[Ref]



Very common (10% or more): Insomnia

Common (1% to 10%): Altered mood (anxiety, nervousness, euphoric mood), sleep disorders

Uncommon (0.1% to 1%): Depression, hallucinations, nightmares, amnesia

Rare (less than 0.1%): Delirium, dependency

Frequency not reported: Depersonalization, paranoia

Postmarketing reports: Abuse


Frequency not reported: Psychic reactions including mood changes, withdrawal symptoms[Ref]

A psychic reaction with symptoms of nervousness, anxiety, agitation, tremor, spasticity, euphoria, emotional lability, and hallucinations has been reported with tramadol use. During clinical trials, tolerance development was mild and the reports of a withdrawal syndrome were rare. Symptoms of a withdrawal syndrome have included: panic attacks, severe anxiety, hallucinations, paresthesias, tinnitus and unusual CNS symptoms (i.e. confusion, delusions, personalization, derealization, and paranoia).[Ref]



Very common (10% or more): Nausea (up to 18%), constipation (up to 11%)

Common (1% to 10%): Vomiting, dyspepsia, dry mouth, diarrhea, abdominal pain, flatulence

Uncommon (0.1% to 1%): Dysphagia, melena, tongue edema


Frequency not reported: Gastrointestinal bleeding[Ref]

Nervous system


Very common (10% or more): Dizziness (up to 15%), Somnolence (up to 12%), headache (up to 11%),

Common (1% to 10%): Tremor, confusion, paresthesia, hypoesthesia

Uncommon (0.1% to 1%): Migraine, hypertonia, stupor, involuntary muscle contractions

Rare (less than 0.1%): Seizures, ataxia, speech disorders


Frequency not reported: Serotonin syndrome[Ref]


Common (1% to 10%): Sweating, pruritus, rash

Uncommon (0.11% to 1%): dermal reactions such as rash and urticaria[Ref]


Uncommon (0.1% to 1%): Albuminuria, micturition disorders (dysuria and urinary retention)

Frequency not reported: Impotence[Ref]


Postmarketing reports of QT prolongation and/or torsade de pointes have been received for tramadol-containing products. In many cases, patients were taking another drug associated with QT prolongation, had risk factors for QT prolongation such as hypokalemia, or in the overdose setting.[Ref]


Uncommon: Hypertension, palpitations, tachycardia, arrhythmia

Less than 1%: Aggravated hypertension, hypotension, chest pain


Frequency not reported: Postural hypotension, bradycardia, syncope, vasodilation, myocardial ischemia

Postmarketing reports: QT prolongation/torsade de pointes[Ref]



Frequency not reported: Allergic reactions (primarily skin rash)


Rare (less than 0.1%): Anaphylaxis, allergic reactions such as dyspnea, bronchospasm, wheezing, urticarial and Stevens-Johnson syndrome/TENS[Ref]



Uncommon (0.1% to 1%): Dyspnea


Frequency not reported: Asthma aggravated[Ref]


Common (1% to 10%): Asthenia, fatigue, hot flushes

Uncommon (0.1% to 1%): Tinnitus, shivers[Ref]



Frequency not reported: Anemia


Frequency not reported: Blood dyscrasias including thrombocytopenia and agranulocytosis[Ref]


Uncommon (0.1% to 1%): Abnormal vision

Rare (less than 0.1%): Blurred vision, mydriasis, miosis[Ref]


Common (1% to 10%): Anorexia

Frequency not reported: Hypoglycemia, decreased weight

Postmarketing reports: Hyponatremia[Ref]

Severe hyponatremia and/or SIADH have been reported, most often in females over 65 years old, and within the first week of therapy.[Ref]


Common (1% to 10%): Prostatic disorder


Postmarketing reports: Adrenal insufficiency; androgen deficiency[Ref]


1. (2001) "Product Information. Ultracet (acetaminophen-tramadol)." Johnson and Johnson Medical Inc

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

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

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.