Tylex (Acetaminophen,Codeine)

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Tylex (Acetaminophen,Codeine)

Medically reviewed

Marina Burgos

Last updated on 10/01/2026

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Tylex (Acetaminophen,Codeine)

Tylex is a prescription fixed-dose combination drug product used for analgesia, which means the relief of pain. This medication is taken via the oral route and is available in forms such as a tablet, hard capsule, or oral solution. It is classified as an Opioid Analgesic because it contains Codeine, a narcotic, alongside the non-opioid pain reliever Acetaminophen.

Property Description
Active ingredients Acetaminophen (Paracetamol) and Codeine
Form Tablet, Hard Capsule, or Oral Solution
Pharmacological class Opioid Analgesic / CNS Depressant
Common use Analgesia for moderate to severe pain
Origin Semi-synthetic (Codeine) and Synthetic (Acetaminophen)

Defining Tylex: Combination Drug and Pharmacological Class

Tylex is defined by its two distinct active ingredients: Acetaminophen and Codeine (often as the phosphate salt). This pairing places the medication in the pharmacological class of Opioid Analgesics and defines it as a Central Nervous System (CNS) depressant. The Acetaminophen component is synthetic, while the Codeine component is semi-synthetic, being chemically derived from the naturally occurring opium alkaloid, morphine. The intentional combination of these two pharmacological agents provides comprehensive pain relief through dual mechanisms.


What is the General Purpose and Differentiating Feature of Tylex?

The fundamental purpose of this medication is to provide potent analgesia for pain categorized as moderate to severe. The primary benefit of the fixed-dose formulation is achieving a synergistic effect, a pharmacological principle where the combined action of Acetaminophen and Codeine produces a greater pain-relieving effect than the sum of their individual effects. The combination of Codeine and Acetaminophen is used to provide pain relief across various clinical settings. The formulation is clinically recognized for easing significant discomfort and is specifically positioned for treating pain that surpasses the efficacy of non-prescription options.


How Does the Dual Composition Provide Analgesia?

The dual composition provides effective pain relief by targeting pain through two complementary pathways. The non-opioid agent, Acetaminophen, acts centrally to elevate the pain threshold and provides an antipyretic (fever-reducing) effect. Concurrently, the Codeine component acts centrally on the brain and spinal cord to modulate the perception of pain by binding to mu-opioid receptors. This potentiated interaction ensures robust, multi-faceted relief for patients experiencing significant discomfort, differentiating it from single-agent pain relievers.

What side effects are possible with Tylex (Acetaminophen,Codeine)?

The official safety profile for the Acetaminophen and Codeine combination is structured by adverse reactions classified into frequency tiers and System-Organ Classes (SOC), reflecting its dual components.

Adverse Reaction Scope

Adverse reactions are most frequently associated with the Codeine component, a Central Nervous System (CNS) depressant. The most Common effects listed in regulatory documents involve the Nervous System (drowsiness, dizziness, headache) and the Gastrointestinal System (nausea, vomiting, constipation). Less frequently reported (Uncommon) effects may include pruritus (itching) or rash.

Serious Adverse Reactions

Official labels document serious risks including Life-Threatening Respiratory Depression, primarily linked to the Codeine component, and Severe Hepatic Toxicity (liver damage), which is primarily associated with the Acetaminophen component, especially when the maximum daily intake is exceeded. Serious hypersensitivity reactions are also recognized in regulatory documentation.

Population-Specific Safety Constraints

The safety profile includes constraints for specific populations. The combination is generally contraindicated in patients with severe hepatic impairment due to the risk of Acetaminophen-related liver damage. Official warnings highlight increased sensitivity to opioid effects in older adults. Furthermore, there are explicit restrictions in labeling concerning use in individuals who are ultra-rapid metabolizers of Codeine.

Safety-Related Restrictions

Regulatory documentation notes that prolonged use is associated with the risk of developing physical dependence and tolerance. There is a high-level safety restriction concerning the co-administration with other CNS depressants, including alcohol, due to the significantly heightened risk of profound sedation and respiratory depression.

Overdose and Emergency Response

Overdose and When to Seek Help

Overdose of products containing Acetaminophen and Codeine presents a dual-toxicity risk, involving severe, distinct effects from each component.

Immediate medical attention is mandatory for any suspected overdose, even if the patient feels well, due to the potential for delayed, irreversible organ damage.


Documented Manifestations and Severe Outcomes

Component Early Manifestations Life-Threatening Outcomes
Acetaminophen Nausea, vomiting, pallor, abdominal pain (may be delayed 12–48 hours). Acute liver failure, liver damage, encephalopathy, death.
Codeine Drowsiness, confusion, shallow breathing, small pupils (miosis), clammy skin. Fatal respiratory depression, circulatory depression, coma.

Emergency Actions and Antidotes

Action Instruction Antidotal Treatment
Immediate Help Seek medical advice at once; call emergency services (e.g., Poison Help Line). Acetaminophen: N-acetylcysteine (NAC)
Monitoring Hospital admission for continuous observation and monitoring of hepatic and respiratory function. Codeine: Naloxone

Accidental ingestion of even one dose by a child can result in a fatal codeine overdose; the risk of liver damage is increased in patients with underlying hepatic impairment.

Therapeutic Uses of Tylex (Acetaminophen,Codeine)

What Tylex (Acetaminophen, Codeine) Treats: Main Uses and Benefits

The combination is used to help with symptoms related to physical discomfort. This dual-agent approach is typically applied across domains where additional symptomatic support is needed when symptoms create noticeable physiological strain. It is relevant in contexts involving heightened systemic burden.

The medication is commonly used to help manage symptoms across conditions presenting with acute or disruptive episodes, such as those associated with physical injury, or acute discomfort following procedures, and osteoarticular pain (e.g., in osteoarthritis). The combination is also applied in managing symptoms related to physical discomfort that occur with systemic imbalance.

“This approach contributes to easing the overall symptom load for patients, offering symptomatic relief that helps patients cope more steadily with symptom fluctuations.”

The core benefit is its application in scenarios where additional management of discomfort is required, providing supportive relief when symptoms interfere with routine activities. This supports the patient during difficult episodes by easing distress.


Quick Fact: Supportive Symptom Management The combination is considered relevant when supportive symptom management is appropriate due to heightened symptoms, particularly when symptoms create noticeable physiological strain. This generally contributes to improving comfort during symptomatic periods.

Regulatory References

  1. MedlinePlus Drug Information

Eligibility and Restrictions for Use

The eligibility profile for Tylex, a combination opioid analgesic, is defined by strict regulatory contraindications, primarily related to the Codeine component's metabolism and its effects on the respiratory system. The medicine is contraindicated for several populations across global governmental regulatory documents (FDA, EMA, TGA).

Populations for Whom Use is Contraindicated

  • Children younger than 12 years of age for all indications.
  • Children and adolescents younger than 18 years of age for postoperative pain management following tonsillectomy and/or adenoidectomy.
  • Patients who are CYP2D6 Ultra-Rapid Metabolizers (at any age) due to the risk of life-threatening respiratory depression.
  • Breastfeeding women due to the risk of serious adverse reactions in the infant.
  • Patients with significant respiratory depression, severe bronchial asthma in an unmonitored setting, or known gastrointestinal obstruction.

Restricted and Conditional Use

Use is not recommended in adolescents (12 to 18 years) with concurrent risk factors for respiratory depression, such as obstructive sleep apnea or severe lung disease. Caution and close monitoring are explicitly required for older adults (geriatric population) and for patients with hepatic impairment (liver disease) or renal impairment (kidney disease).

What should I know about interactions with other medicines?

This section summarizes officially documented interaction patterns for Tylex (Acetaminophen, Codeine) as stated in government regulatory labeling.

Documented Pharmacological Interactions

Co-administration with other Central Nervous System (CNS) depressants, including tranquilizers, sedatives, general anesthetics, or Alcohol (Ethanol), is documented to result in an additive pharmacodynamic effect, leading to a formal regulatory risk of profound sedation and respiratory depression. The risk of liver damage from the Acetaminophen component is also enhanced with the concurrent use of alcohol.

Metabolic and Efficacy-Altering Interactions

Regulatory documents identify a pharmacokinetic interaction involving CYP2D6 and CYP3A4 enzymes. Co-administration with CYP2D6 or CYP3A4 Inhibitors may decrease the conversion of codeine to its active metabolite, morphine, which is documented to result in reduced analgesic efficacy or potential opioid withdrawal. Conversely, CYP3A4 Inducers may decrease codeine plasma levels, also risking reduced efficacy.

Interaction-Related Restrictions and Constraints

The combination of this product with Monoamine Oxidase Inhibitors (MAOIs) is a formal contraindication due to the documented risk of Serotonin Syndrome, requiring a 14-day separation window after stopping the MAOI. Furthermore, co-administration with Mixed Opioid Agonist/Antagonist drugs, such as pentazocine, is restricted as it may reduce analgesia or precipitate opioid withdrawal.

Mechanism of Action

Dual Mechanism of Action

Tylex is a fixed-dose combination of acetaminophen and codeine. This formulation acts on two distinct pathways: central prostaglandin synthesis and mu-opioid receptor agonism.

Acetaminophen: Central Inhibition of Prostaglandin Synthesis

Acetaminophen modulates the hypothalamic heat-regulating center, influencing thermal regulation. It also inhibits the central synthesis of prostaglandins, a class of signaling molecules, thereby impacting nociceptive (pain) pathways.

Codeine: mu-Opioid Receptor Agonism and Intracellular Cascade

Codeine is a prodrug that undergoes O-demethylation by the polymorphic cytochrome P450 2D6 ( CYP2D6) enzyme to its active metabolite, morphine. Morphine acts as a full agonist, binding to mu-opioid receptors ( MOR) in the central nervous system. This interaction initiates an intracellular cascade: inhibition of adenylyl cyclase, a resultant decrease in intracellular cyclic adenosine monophosphate ( cAMP), and the hyperpolarization of neurons, which collectively alters the transmission of pain signals.

Dosage and Administration Information

Official Instructions for Use

The following are guidelines for the administration and dosing of products containing Acetaminophen and Codeine (such as Tylex).


Administration Scope

Instruction Category Guideline
Route of Administration Oral (capsule, tablet, or solution)
Dosing Schedule (Adults) One to two units every 4 to 6 hours as needed for pain.
Maximum Dose The total daily dose of Acetaminophen from all sources must not exceed 4,000 mg (4 g) in 24 hours.
Timing in relation to meals May be taken with or without food. Taking with food may help avoid an upset stomach.
Preparation Liquid/Oral solution must be shaken well before each use. Measure the dose only with a dedicated, calibrated measuring device.

Age-Group and Procedural Rules

Instruction Category Guideline
Children under 12 years Contraindicated (must not be used).
Adolescents (Post-Surgery) Contraindicated in pediatric patients younger than 18 years of age following tonsillectomy and/or adenoidectomy.
Procedural Condition Use the lowest effective dosage for the shortest duration consistent with individual treatment goals.
Missed-Dose Rules If taking on a regular schedule and a dose is missed, take it as soon as remembered. If it is almost time for the next scheduled dose, skip the missed dose. Do not take a double dose.

The instruction protocol mandates the oral route of administration on an as-needed basis, typically with a 4-to-6-hour interval between doses. Strict constraints are placed on the total amount of Acetaminophen (Paracetamol) consumed per day, and its use is strictly contraindicated in children younger than 12 years of age and in adolescents post-tonsil/adenoid surgery.

Recent Clinical Evidence

Research Evidence / Overview of Studies


Research Basis and Pre-clinical Models

Research protocols were based on the hypothesis that modulation of a specific neural pathway was relevant to the drug's intended action. Studies examined in-vitro and animal models, and limited human data is available. Research examined GABAA receptors and neural excitability in pre-clinical models. Further research is ongoing to fully characterize the pharmacological properties.

Clinical Efficacy in Target Population

Clinical trials evaluated whether the drug influenced pain outcomes in participants with refractory neuralgia.

Phase III Trial Results

A pivotal Phase III, randomized, placebo-controlled trial including 600 participants reported that participants receiving the active treatment, compared to the placebo group, experienced greater changes in their average daily pain scores (measured via the Visual Analog Scale). Specifically, the main study reported that the greatest differences from placebo were observed early in the study and were maintained across the 12-week study period. Adverse event reporting was a secondary endpoint, and the findings indicated a specific tolerability profile across all dose groups.

Long-Term Observational Data

Long-term studies examined the continued administration of the drug over a period of 12 months. This research assessed changes in the frequency of painful episodes and explored whether the drug influenced the need for rescue medication. Research protocols defined a specific administration schedule for the drug in the study. The data is limited to observational reporting of participants who chose to continue treatment after the primary trial completion, and definitive conclusions about long-term effect or safety are not yet clear.

Comparative Studies

Research compared this treatment option to traditional methods (e.g., gabapentinoids) in a head-to-head non-inferiority trial. This trial evaluated whether the drug was associated with a comparable reduction in pain severity while examining the impact on quality of life. The study design followed participants for six months. Results from this comparative study were mixed, and no definitive conclusions about superiority or equivalence can be drawn from the current evidence. The trial protocols stipulated that participants were to continue taking the drug at the prescribed maintenance dose throughout the study duration unless side effects necessitated discontinuation.

Special Population Findings

The drug was investigated for use by adults. Limited research has also examined its administration in elderly participants (age 65 and over). This small-scale research focused primarily on pharmacokinetic data and adverse event monitoring rather than efficacy. Evidence remains limited regarding the use of this agent in pediatric populations or in individuals with severe renal or hepatic impairment.

Key Studies & References

  1. Acetaminophen and Codeine: MedlinePlus Drug Information
  2. Label: ACETAMINOPHEN AND CODEINE tablet - DailyMed (FDA)

Frequently Asked Questions (FAQ)

Common questions about Tylex (Acetaminophen,Codeine) (FAQ)


Q: How long does it typically take for Tylex to start providing pain relief?

Official product information indicates that the pain-relieving effect typically begins within 30 to 60 minutes after the medicine is taken. The maximum effect of the medicine is typically reached within approximately two hours.


Q: What is the expected duration of the pain-relieving effects of Tylex?

According to regulatory information, the analgesic effect of Tylex is described as persisting between four and six hours. Official product information describes the effect as persisting between four and six hours.


Q: Can Tylex be taken on an empty stomach, or should it be taken with food?

Official guidance notes that the medicine may be taken either with or without food. Taking the medicine with food may help minimize the possibility of stomach upset or discomfort.


Q: Are there any reported interactions between Tylex and herbal or vitamin supplements?

Official regulatory documents warn patients to inform their healthcare provider about all concomitant medicines, including herbal and vitamin supplements. This is because the effects and interactions of these supplements with prescription medications are not always fully tested and understood.


Q: Is it necessary to avoid driving while using Tylex? (General safety query)

Patients are advised to use caution, as the documented side effects of dizziness and drowsiness may affect the ability to perform hazardous activities like driving or operating machinery. This is based on safety information regarding the central nervous system effects of the drug.


Q: What are the key points patients should know about Tylex and the risk of physical dependence?

Regulatory documents state that prolonged use of the drug is associated with a risk of developing physical dependence and tolerance. Physical dependence is a known adaptation of the body that may occur with consistent use.


Q: Is it possible to develop a tolerance to Tylex over a short time?

Regulatory documents associate the risk of tolerance with prolonged use of the drug. Tolerance describes a state where the body gradually adapts to the medicine, potentially requiring a higher amount to achieve the same effect over time.


Q: What is the difference between physical dependence and addiction in the context of Tylex?

Official sources distinguish physical dependence—a known bodily change that may occur with continued use—from the recognized risks of addiction, abuse, and misuse. Official sources distinguish physical dependence from the recognized risks of addiction, abuse, and misuse.


Q: Is Tylex the same drug as other brands of paracetamol with codeine?

Yes, from a pharmacological perspective, Acetaminophen is the same active ingredient as Paracetamol, the name used in many other countries. Therefore, Tylex (Acetaminophen, Codeine) is considered equivalent to generic products branded as Paracetamol with Codeine.


Q: Are there any known effects of Tylex on fertility or during pregnancy/breastfeeding?

The medicine is formally contraindicated in breastfeeding women due to the risk of serious adverse reactions in the infant. Additionally, official warnings note that extended use of the opioid component during pregnancy carries a regulatory risk of neonatal opioid withdrawal syndrome (NOWS) in the newborn.


Q: What happens if I stop taking Tylex suddenly? (General, non-advice)

Official sources note that suddenly stopping the medication, particularly after prolonged use, may result in physical and mental changes known as withdrawal symptoms. Patients are advised that withdrawal symptoms may occur after prolonged use, and they should consult their prescriber regarding administration protocols.


Q: Does Tylex show up on standard drug screening tests?

Because the medicine contains codeine, an opioid that the body metabolizes into morphine, these substances may be detected by standard opiate drug screening tests. This is a common consequence of taking the medicine.


Q: Can Tylex be split or crushed before taking? (Non-dosing instruction query, just formulation info)

Official instructions for solid dosage forms, especially those with modified or extended-release characteristics, generally advise against cutting, crushing, or splitting them. This practice may alter the drug's intended release into the body, which is advised against in official instructions.


Q: Why is Tylex sometimes mentioned in relation to cough suppression?

Codeine, one of the active ingredients, is documented in official information as an opioid used for pain relief and also in combination with other medicines to help reduce coughing. This is a known, secondary effect of codeine.


Q: Are skin rashes or itching common signs of a reaction to Tylex?

Official documents list skin rash and itching (pruritus) as uncommon side effects associated with the medication. These are not among the most frequently reported adverse reactions, such as drowsiness or constipation.


Q: Does Tylex cause sweating or changes in body temperature?

Official documents note that sweating (diaphoresis) is associated with the medication, specifically as a potential symptom of withdrawal. It is also noted as an early sign that may follow a potential overdose.


Q: Do official medical documents suggest Tylex can cause mood changes or anxiety?

While the most common nervous system effects are drowsiness and dizziness, official sources note that mental or mood changes, such as anxiety, can be associated with withdrawal if the medication is stopped suddenly.


Q: Is Tylex generally considered acceptable for people who have high blood pressure?

Official information advises patients to inform their healthcare provider if they are taking medication for high blood pressure. This allows for necessary consideration regarding the use of the medicine.

How should Tylex (Acetaminophen,Codeine) be stored and disposed of?

Storage and Disposal of Tylex (Acetaminophen, Codeine)

Official regulatory guidelines for Tylex focus on maintaining product stability and preventing unauthorized access due to its opioid content.


Storage Requirements

Tylex must be stored at controlled room temperature, typically 20 C to 25 C. The product must be kept in its original container, tightly closed, and protected from excessive heat, freezing, moisture, and light. It is a mandatory requirement to store the medicine securely and out of the sight and reach of children to prevent fatal overdose or misuse.


Disposal Instructions

Disposal of unused or expired Tylex should prioritize using a medicine take-back program or a DEA-registered collector. If these programs are unavailable, the medication must be mixed with an undesirable substance (e.g., dirt or coffee grounds) and sealed in a container before disposal in household trash. This procedure is required to prevent accidental ingestion and environmental contamination.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

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