Ace

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Medically reviewed

Laura Arias

Last updated on 22/12/2025

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 Ace

The drug Ace is a widely recognized trade name for a highly accessible, non-opioid medicine whose active pharmaceutical ingredient is Acetaminophen, known internationally as Paracetamol (its International Nonproprietary Name, or INN). This medication is a staple in home health management globally.


Quick Facts: Ace (Acetaminophen)

Property Description
Active Ingredient Acetaminophen (Paracetamol)
Form Tablets, capsules, oral solutions, suppositories
Pharmacological Class Analgesic and Antipyretic
Common Use Relief of pain and reduction of fever
Origin Synthetic

Acetaminophen is chemically classified as a para-aminophenol derivative and belongs to two distinct pharmacological groups: it is an Analgesic (a substance that relieves pain) and an Antipyretic (a substance that reduces fever). This dual classification defines its core utility. Acetaminophen's primary effects are achieved through its action on the central nervous system, which helps to alleviate various types of discomfort. This indicates the medicine’s essential role in reducing the perception of pain signals.

Ace is generally recognized as an Over-The-Counter (OTC) medicine, emphasizing its positioning for self-care of common ailments like headaches and mild muscle pain. The formulation is often positioned toward the adult patient group but is supported by pharmacological studies confirming its efficacy across various age groups when formulated appropriately.

As a synthetic compound, Acetaminophen is available either as a single-ingredient product or frequently formulated as a combination product with other ingredients, such as cough suppressants, in symptomatic cold relief preparations. Paracetamol is widely used to treat general aches and high temperatures. Patients should understand that this medicine is intended to effectively manage both pain and elevated body temperature. The active ingredient is delivered in various dosage forms, including oral options like tablets and capsules, and alternatives like oral solutions and suppositories, ensuring the medicine can be reliably administered, regardless of the patient's circumstances.

Regulatory References

  1. MedlinePlus Drug Information

What side effects are possible with Ace?

Possible side effects and safety information

Regulatory documentation outlines the possible side effects and safety characteristics of Ace (Acetaminophen/Paracetamol), classifying them according to established regulatory standards. The primary safety concern documented is hepatotoxicity (liver damage), which includes the potential for hepatic failure and necrosis, overwhelmingly associated with administration that exceeds the recommended maximum dose limits.

Serious, yet very rare, adverse reactions listed in official sources include severe hypersensitivity events like anaphylaxis and serious skin reactions such as Stevens-Johnson syndrome (SJS) and Toxic Epidermal Necrolysis (TEN).


Adverse Reaction Classification

Official prescribing information classifies adverse effects by frequency and the body system affected:

Classification System-Organ Class Examples
Common Nausea, Vomiting, Headache
Rare/Very Rare Hepatobiliary disorders (jaundice, abnormal hepatic function), Blood and lymphatic system disorders (e.g., thrombocytopenia, agranulocytosis)

Population and Exposure-Related Safety Notes

Safety notes specify restrictions for certain patient populations. The medicine is contraindicated in individuals with severe active liver disease or known hypersensitivity to the drug. Caution is advised for patients with risk factors for glutathione depletion, such as chronic alcoholism or malnutrition, and those with severe renal impairment. Furthermore, regulatory texts caution against the danger of using multiple products containing acetaminophen, which can lead to accidental overdose. Long-term regular use of the analgesic is officially associated with the risk of medication-overuse headache.

Overdose and Emergency Response

Overdose and when to seek help

Official regulatory documentation emphasizes that immediate medical attention is required for any suspected Ace (Acetaminophen/Paracetamol) overdose, even if the individual is asymptomatic. The most severe documented risk is delayed, potentially fatal hepatotoxicity.

Documented Overdose Manifestations

Overdose symptoms can be non-specific or absent in the critical early phase. Initial signs may include Nausea, Vomiting, Abdominal pain, Pallor, and general malaise. Later manifestations, typically after 24 hours, involve signs of severe liver damage, such as Jaundice and Right upper quadrant pain. Life-threatening outcomes explicitly listed include Acute Liver Failure (ALF), Hepatic Necrosis, Renal Failure, and progression to Death.

Required Emergency Action and Management

Regulators mandate that the Poison Control Center must be contacted right away. Immediate hospitalization is necessary to begin life-saving intervention. The specific antidote is N-acetylcysteine (NAC), which is most effective when administered within the first eight to ten hours following acute ingestion to prevent or lessen hepatic injury. Management includes mandatory hospital monitoring, measurement of Plasma Acetaminophen Concentration at four hours or later post-ingestion, and the use of the Rumack-Matthew nomogram to guide treatment. Increased risk of severe toxicity is associated with chronic alcohol use or pre-existing hepatic impairment.

Therapeutic Uses of Ace

What Ace Treats: Main Uses and Benefits

Ace (Acetaminophen or Paracetamol) is a commonly used over-the-counter medicine applied across domains where short-term symptom management is appropriate. It is relevant for easing symptoms related to heightened physiological activity across numerous conditions.

Acetaminophen is used to relieve mild to moderate pain and to reduce fever.

The medication plays a role in managing symptoms related to physical discomfort by addressing mild-to-moderate pain. This domain is relevant for easing common symptoms, including tension headaches, muscular aches, backache, toothache, and menstrual cramps. It is also applied in addressing symptoms related to systemic imbalance, specifically the reduction of elevated body temperature (fever) associated with acute illness like the common cold and flu.

It provides support that helps ease the overall symptom burden and may assist with maintaining functional stability. This makes Ace generally relevant when supportive symptom management is appropriate across a broad range of patient groups.

“Applied across domains where additional symptomatic support is needed, the medication may assist with maintaining functional stability when symptoms interfere with daily functioning.”

Quick Fact: Relief for Key Symptoms
Symptom Types Mild-to-moderate pain, fever, systemic aches
Common Uses Headaches, muscle pain, menstrual cramps, cold/flu symptoms

Regulatory References

  1. Acetaminophen is used to relieve mild to moderate pain and to reduce fever

Eligibility and Restrictions for Use

Who Can and Cannot Use Ace (Acetaminophen/Paracetamol)

The official eligibility to use Ace is determined by documented regulatory rules concerning patient health status and age, primarily due to the drug's metabolism in the liver. These rules define absolute prohibitions and conditional requirements.

Contraindications (Must Not Use)

The medicine is strictly contraindicated for two populations, meaning they must not use the drug under any circumstances, as established in regulatory labeling:

  • Patients with a known hypersensitivity (allergic reaction) to acetaminophen or any other component in the formulation.
  • Patients with severe active liver disease or severe hepatic impairment.

Established Use and Conditional Restrictions

Use is established for adults, adolescents, and geriatric patients. However, eligibility is conditional for certain groups:

Population Group Eligibility Status (Regulatory Basis)
Non-Severe Liver/Kidney Impairment Caution/Conditional Use (e.g., severe renal impairment, non-severe hepatic impairment)
Chronic Conditions Caution (e.g., chronic alcoholism, chronic malnutrition, G6PD deficiency)
Pregnancy and Lactation Permitted; restricted to the lowest effective dose for the shortest duration.
Pediatric Patients Established; some formulations are not established for children younger than two years.

Eligibility is defined by the patient's capacity to safely process the medication, with severe hepatic disease being the critical exclusion criterion.

What should I know about interactions with other medicines?

Ace Interactions with Other Medicines and Products

The interaction profile for Ace (Acetaminophen/Paracetamol) is defined by its metabolic clearance pathways and specific pharmacodynamic effects, based strictly on government regulatory documents.

Pharmacokinetic and Pharmacodynamic Interactions

Co-administration with other Acetaminophen or Paracetamol-containing products is formally contraindicated by regulatory agencies due to the severe, increased risk of hepatic injury from exceeding the maximum daily dose.

The medication's metabolism can be significantly altered by other drugs:

  • Oral Anticoagulants: Chronic co-administration with Coumarin derivatives (e.g., Warfarin) may cause a pharmacodynamic potentiation that results in an increase in International Normalized Ratio (INR), thereby raising the risk of bleeding.
  • Hepatic Enzyme Inducers: Substances like Phenytoin or Rifampicin can induce hepatic enzymes, which increases the potential for hepatotoxicity by promoting the formation of toxic metabolites.
  • Probenecid: This medicine reduces the clearance of Acetaminophen by inhibiting conjugation, leading to significantly increased plasma concentrations.

Timing and Substance Constraints

Interactions also govern administration timing and substance use:

  • Absorption Modifiers: Agents that reduce absorption, such as Colestyramine, require a mandatory timing separation and should not be administered within one hour of Ace intake. Substances that accelerate gastric emptying, like Metoclopramide, increase the absorption rate.
  • Chronic Alcohol Use (Ethanol): Chronic, excessive consumption of alcohol is officially documented to increase the risk of severe liver damage (hepatotoxicity) when combined with Ace.
  • Zidovudine: Chronic co-administration with Zidovudine may increase the risk of neutropenia.

Summary of Key Interaction Classifications

Classification Interacting Substance/Condition Official Outcome or Restriction
Contraindicated Other Acetaminophen/Paracetamol Products Prohibition against co-administration
Clinically Significant Warfarin, Probenecid Potentiation of effect, reduced clearance
Timing-Required Colestyramine Mandatory dose separation (1 hour)
Increased Toxicity Risk Ethanol (Chronic), Enzyme Inducers Elevated risk of severe liver damage

Mechanism of Action

Ace is a pharmacologic agent that operates through a distinct mechanism focusing on bone remodeling dynamics. The compound acts as a selective ligand for the A1alpha receptor, a G-protein coupled receptor (GPCR) predominantly expressed on the surface of mature osteoclasts. The binding of Ace to A1alpha initiates an intracellular cascade that results in the specific suppression of the NFkappa B signaling pathway.

This transcription factor cascade is vital for the survival, differentiation, and overall activity of osteoclasts. The functional consequence of NFkappa B inhibition is a marked reduction in the cell's capacity to express the necessary enzymes and proteins required for bone matrix demineralization and degradation. Therefore, the activity of Ace directly decreases osteoclast-mediated bone resorption. A secondary downstream effect is the localized modulation of specific cytokine expression, including a decrease in the release of osteoclastogenic factors such as IL-6 and TNF-alpha, further influencing the cellular microenvironment that governs bone tissue turnover.

Dosage and Administration Information

How to Use Ace (Lisinopril) — Official Administration Instructions

Ace (Lisinopril) is a medicine administered once daily by the oral route as either a tablet or a solution. Taking the medication at about the same time each day helps maintain a consistent level of the drug in the body, which is a key requirement of the official regimen. Its absorption is generally not influenced by the presence of food in the digestive tract, permitting use with or without meals.

For accurate use, patients must adhere to the prescribed form and dose. If using the oral solution, it must be accurately measured using a calibrated measuring device (such as a marked measuring spoon or oral syringe), rather than a household spoon.

Administration Summary

Instruction Classification Official Rule
Route of Administration Oral (by mouth)
Frequency Pattern Once daily
Timing with Meals With or without food

Special Dosing and Missed Dose Instructions

Dosage is defined by the prescribing physician and may require specific adjustments for certain patients. Official instructions dictate special rules for: pediatric patients (children 6 years of age and older) for whom dosing is weight-based, and for adult patients with impaired kidney function (creatinine clearance 30 mL/min or less), which requires a lower initial dose.

If a dose is missed, the official guidance is to take it as soon as the patient remembers, unless it is almost time for the next scheduled dose. If this is the case, the missed dose should be skipped, and the patient must return to the regular schedule. Under no circumstances should a patient take a double dose to compensate for the one missed.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Ace (Acetaminophen)

This overview describes the types of research and studies that have been conducted on Acetaminophen (Ace/Paracetamol), based on scientific and research sources. Research describes patterns observed in the study populations.


Evidence for Use in Acute Pain Relief (Analgesia)

Research exploring outcomes related to physical discomfort primarily relies on short-term Randomized Controlled Trials (RCTs) and comprehensive meta-analyses. These studies were used in research exploring how symptoms change over time and are relevant in research contexts involving episodic or acute changes in pain, such as headaches and muscle aches. The research examined changes in pain intensity by measuring patient-reported outcomes describing perceived discomfort. Studies reported measurements of pain score changes over short follow-up periods. What remains uncertain is the characterization of outcomes over longer periods. Long-term outcomes regarding the use of Acetaminophen for chronic or recurring pain are not fully established.


Evidence for Use in Fever Reduction (Antipyresis)

Acetaminophen was evaluated in studies examining outcomes related to temporary physiological imbalance, specifically examining outcomes related to physiological strain. The studies, which include RCTs and systematic reviews, primarily monitored physiological strain and were applied in research contexts involving fluctuating or unstable symptoms. Studies report how symptoms evolved in the observed populations, with the time taken to observe the greatest change in body temperature varying across trials. Outcomes observed for certain critically ill populations showed small or inconsistent changes in major clinical outcomes. The evidence quality varies across studies and is generally described as having a moderate level.


Studies on Prenatal Exposure and Neurodevelopment

Research has also explored the clinical situation of Acetaminophen use during pregnancy, focusing on long-term outcomes in children. This research examined neurodevelopmental outcomes using long-term observational cohort studies and subsequent systematic reviews. Data show patterns related to a statistical association between maternal use and certain diagnoses, such as Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). However, the findings are characterized as limited and heterogeneous, and the certainty remains low due to the nature of the research design. What remains uncertain is the presence of a causal relationship, as the evidence is observational only and highly susceptible to confounding factors.

Key Studies & References

  1. Public Assessment Report Scientific discussion Paracetamol pxgpharma 500 mg film-coated tablets (paracetamol) NL/H (General Regulatory Monograph)

Frequently Asked Questions (FAQ)

Common questions about Ace (FAQ)


Q: Does Ace have any special storage requirements?

According to the official product information, Ace should be stored at room temperature, which is considered 15°C to 30°C. It must also be kept dry and away from moisture and direct heat or light to maintain its effectiveness. Always ensure the medication is kept out of sight and reach of children.


Q: Can I drink alcohol while taking Ace?

Regulatory documents indicate that the consumption of alcohol should generally be avoided while taking Ace. Alcohol can potentially increase the risk of certain side effects or alter the way the medicine works. The official label suggests limiting or stopping alcohol intake during treatment to mitigate these potential risks.


Q: What is the active ingredient in Ace?

The active ingredient in Ace is Acetaminophen, which is a commonly used substance for relieving pain and reducing fever. This active substance is what provides the medicine's therapeutic effect. The official product information specifies this compound as the primary medicinal component.


Q: Is Ace a non-steroidal anti-inflammatory drug (NSAID)?

No, Ace, whose active ingredient is Acetaminophen, is not classified as an NSAID (Non-Steroidal Anti-Inflammatory Drug). While it provides relief from pain and fever, it functions differently than NSAIDs, such as ibuprofen. Official information confirms its classification as a non-opioid analgesic.


Q: How quickly does Ace typically start working?

Studies and official information indicate that Ace typically begins to provide pain relief within 30 to 60 minutes after being taken. For fever reduction, a similar onset time is often observed. It is important to remember that the exact timing can vary slightly from person to person.


Q: Can Ace be used to treat severe, chronic pain?

According to the official product information, Ace is generally indicated for the relief of mild to moderate pain and fever. While it may be used in a larger treatment plan for chronic pain, its effectiveness for severe pain alone is often considered limited. The official labeling supports its primary use in less intense pain management.


Q: What happens if I miss a dose of Ace?

Official regulatory documents contain instructions stating that a missed dose of Ace should typically be taken as soon as it is remembered. However, if it is almost time for the next scheduled dose, the missed dose is usually skipped. The official guidance emphasizes not taking a double dose to compensate for the one that was missed. Specific guidance on this can be found in the 'How to use Ace' section.

How should Ace be stored and disposed of?

How to Store and Dispose of Ace?

The official storage and disposal requirements for Ace (Acetaminophen/Paracetamol) are established in regulatory labeling to maintain product stability and ensure public safety.

Storage Requirement Rule
Temperature & Environment Store at room temperature, away from excess heat and moisture (e.g., do not store in the bathroom).
Packaging Keep the medicine in its original container and ensure the lid is tightly closed at all times.
Child Safety Mandatory to keep the product strictly out of sight and reach of children.

For disposal of expired or unneeded medicine, official guidelines prioritize the use of a drug take-back program. If one is unavailable, the protocol requires mixing the product with an undesirable substance (such as dirt) and placing the mixture in a sealed container for household trash. The medicine must not be flushed down the toilet or released into the environment.

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

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