We unleash your business potential by maximize the business innovation.
Send EmailParacetamol, Acetaminophen, N-Acetyl-4-aminophenol, APAP, 103-90-2
| Property | Information |
|---|---|
| Chemical Name | N-(4-hydroxyphenyl)acetamide |
| Synonyms | Paracetamol, Acetaminophen, APAP, 4-Acetamidophenol, 4'-Hydroxyacetanilide, N-Acetyl-4-aminophenol |
| Chemical Formula | C₈H₉NO₂ |
| Molecular Weight | 151.16 g/mol |
| CAS Number | 103-90-2 |
| EC Number (EINECS) | 203-157-5 |
| Appearance | White, crystalline powder |
| Odor | Odorless |
| Drug Class | Analgesic, Antipyretic (Weak anti-inflammatory) |
| Property | Value |
|---|---|
| Physical State (20°C) | Solid (crystalline powder) |
| Appearance | White to off-white crystalline powder |
| Odor | Odorless |
| Molecular Weight | 151.16 g/mol |
| Melting Point | 168 – 172 °C |
| Density | ~1.26 g/cm³ |
| Solubility in Water (20°C) | Sparingly soluble (approx. 14 g/L) |
| Solubility in Ethanol | Freely soluble (~750 g/L) |
| Solubility in Acetone | Freely soluble |
| Solubility in Ether | Practically insoluble |
| Log P (octanol/water) | 0.46 |
| pKa | 9.5 (phenolic OH) |
| UV Absorption (λmax) | 249 nm (in water) |
| Property | Information |
|---|---|
| Chemical Formula | C₈H₉NO₂ |
| Molecular Weight | 151.16 g/mol |
| Chemical Class | Para-aminophenol derivative |
| Structure | Benzene ring with OH (para) and NHCOCH₃ (meta) substituents |
| IUPAC Name | N-(4-hydroxyphenyl)acetamide |
| SMILES | OC1=CC=C(NC(C)=O)C=C1 |
| InChI Key | RZVAJINKPMORJF-UHFFFAOYSA-N |
| Stability | Stable under normal storage conditions; protect from light |
| Hygroscopicity | Low (non-hygroscopic) |
| Incompatible Materials | Strong oxidizing agents, strong bases |
Chemical Structure:
HO-C₆H₄-NH-CO-CH₃
| Parameter | Description |
|---|---|
| Primary Mechanism | Selective inhibition of cyclooxygenase-2 (COX-2) in the central nervous system (CNS) |
| COX-1 Inhibition (ex vivo) | IC₅₀ ~113.7 μM (56% inhibition at 1000 mg dose) |
| COX-2 Inhibition (ex vivo) | IC₅₀ ~25.8 μM (83% inhibition at 1000 mg dose) |
| Selectivity | Approximately 4.4-fold selectivity for COX-2 over COX-1 |
| Key Difference from NSAIDs | Does not significantly inhibit COX-1 in peripheral tissues (minimal GI effects, no antiplatelet activity) |
Key Points:
Unlike traditional NSAIDs (ibuprofen, naproxen), paracetamol has weak anti-inflammatory effects
Acts primarily centrally (CNS) rather than peripherally
Does not cause gastric irritation (minimal COX-1 inhibition in stomach)
Does not affect platelet function (no bleeding risk)
| Parameter | Description |
|---|---|
| Normal Metabolism | Glucuronidation (~55%), sulfation (~30%), CYP450 oxidation (~10-15%) |
| Toxic Metabolite | NAPQI (N-acetyl-p-benzoquinone imine) – produced via CYP2E1 |
| Normal Disposition | NAPQI is rapidly detoxified by hepatic glutathione |
| Overdose Mechanism | Glutathione reserves are depleted; NAPQI accumulates causing hepatocyte necrosis |
| Antidote | N-Acetylcysteine (NAC) – replenishes glutathione stores |
| Form | Strength | Route | Notes |
|---|---|---|---|
| Immediate Release Tablet | 500 mg | Oral | Most common form |
| Effervescent Tablet | 500 mg + excipients | Oral | Faster absorption |
| Dispersible Tablet | 500 mg | Oral | Dissolves in water |
| Suspension (Oral) | 120 mg/5 mL, 160 mg/5 mL | Oral | For pediatrics |
| Suppository | 60 mg, 125 mg, 250 mg, 500 mg | Rectal | When oral not possible |
| IV Injection | 10 mg/mL | Intravenous | Hospital use |
| Application | Description | Evidence Level |
|---|---|---|
| Acute Pain (Mild to Moderate) | Headache, migraine, toothache, dysmenorrhea, musculoskeletal pain | Strong |
| Fever (Pyrexia) | Reduces elevated body temperature | Strong |
| Post-operative Pain | Mild to moderate post-surgical pain | Strong |
| Osteoarthritis | Chronic pain (though NSAIDs more effective) | Moderate |
| Combination | Typical Strengths | Purpose | Reference |
|---|---|---|---|
| Paracetamol + Codeine | 500 mg + 8 mg / 300 mg + 15 mg / 400 mg + 20 mg | Enhanced analgesia (opioid + non-opioid) | WHO, eMC, Canada DPD |
| Paracetamol + Caffeine | 400 mg + 50 mg / 500 mg + 30 mg | Adjuvant for headache; may enhance absorption | VIDAL, eMC |
| Paracetamol + Caffeine + Codeine | 400 mg + 50 mg + 20 mg | Moderate-severe pain | VIDAL |
| Population | Route | Single Dose | Maximum Daily Dose | Frequency |
|---|---|---|---|---|
| Adults (≥50 kg) | Oral | 500 – 1000 mg | 4000 mg | Every 4-6 hours |
| Adults (<50 kg) | Oral | 500 mg | 3000 mg | Every 4-6 hours |
| Children (6-12 years) | Oral | 250 – 500 mg | 1500 – 2000 mg | Every 4-6 hours |
| Children (2-6 years) | Oral | 120 – 250 mg | 1000 – 1200 mg | Every 4-6 hours |
| Infants (3-24 months) | Oral | 60 – 120 mg | 400 – 600 mg | Every 4-6 hours |
| Adults (IV) | IV | 500 – 1000 mg | 4000 mg | Every 4-6 hours |
Important Safety Limits:
Maximum single dose: 1000 mg
Maximum daily dose: 4000 mg (adults with normal liver function)
Minimum dosing interval: 4 hours
Chronic use limit: Consult physician for use beyond 3-5 days
| Parameter | Specification (USP / Ph. Eur.) |
|---|---|
| Appearance | White crystalline powder |
| Assay (dried basis) | 98.5 – 101.0% |
| Identification | Positive (IR, HPLC, Chemical tests) |
| Melting Point | 168 – 172 °C |
| pH (saturated solution) | 5.5 – 6.5 |
| Loss on Drying | ≤ 0.5% |
| Residue on Ignition | ≤ 0.1% |
| Heavy Metals (as Pb) | ≤ 10 ppm |
| Chloride (Cl) | ≤ 0.01% |
| Sulfate (SO₄) | ≤ 0.02% |
| Related Substances (Impurities) | ≤ 0.5% total |
| 4-Aminophenol (toxic impurity) | ≤ 50 ppm (critical limit) |
| Residual Solvents | Meets ICH Q3C requirements |
| Microbial Limits | TAMC ≤ 1000 CFU/g, TYMC ≤ 100 CFU/g, Absence of E. coli, Salmonella |
| Parameter | Information |
|---|---|
| Storage Conditions | Cool, dry, well-ventilated area; 15-25°C recommended |
| Container Requirements | Tightly closed, light-resistant containers (amber glass or opaque HDPE) |
| Protect From | Light, moisture, strong oxidizing agents, strong bases |
| Shelf Life (Pharmaceutical grade) | 36-60 months (when stored properly in unopened packaging) |
| Stability | Stable under normal storage; may discolor if exposed to light/moisture |
| Packaging Options | 25 kg fiber drums with polyethylene liner, 50 kg drums, 500 kg/1000 kg FIBC |
Storage Note: Protect from light to prevent discoloration. Store in original containers with tight closures.
| Hazard Class | Category |
|---|---|
| Acute Toxicity (Oral) | Category 4 (H302) |
| Skin Irritation | Category 2 (H315) |
| Eye Irritation | Category 2A (H319) |
| Specific Target Organ Toxicity (Repeated exposure) | Category 2 (H373) – liver |
| Code | Statement |
|---|---|
| H302 | Harmful if swallowed (at very high doses) |
| H315 | Causes skin irritation |
| H319 | Causes serious eye irritation |
| H373 | May cause damage to organs (liver) through prolonged or repeated exposure (overdose) |
| Code | Statement |
|---|---|
| P261 | Avoid breathing dust |
| P264 | Wash thoroughly after handling |
| P280 | Wear protective gloves and eye protection |
| P301+P312 | IF SWALLOWED: Call a POISON CENTER if you feel unwell |
| P305+P351+P338 | IF IN EYES: Rinse cautiously with water for several minutes |
| Type | Effects |
|---|---|
| Common | Generally well-tolerated at therapeutic doses |
| Less Common | Nausea, vomiting, allergic reactions (rash, urticaria) |
| Serious (Overdose) | Hepatotoxicity (liver damage) – potentially fatal; requires immediate medical attention |
| Very Rare | Stevens-Johnson syndrome, toxic epidermal necrolysis, agranulocytosis |
| Condition | Status |
|---|---|
| Severe hepatic impairment | Absolute contraindication |
| Hypersensitivity to paracetamol | Absolute contraindication |
| Chronic alcoholism (with malnutrition) | Relative contraindication (increased hepatotoxicity risk) |
| G6PD deficiency | Caution (rare hemolytic anemia) |
| Exposure Route | Action |
|---|---|
| Inhalation | Remove to fresh air. Seek medical attention if respiratory irritation occurs. |
| Skin Contact | Wash with plenty of water and soap. |
| Eye Contact | Rinse immediately with plenty of water for at least 15 minutes. Seek medical attention. |
| Ingestion (Therapeutic use) | Unlikely to cause harm at therapeutic doses. |
| Ingestion (Overdose) | Seek immediate medical attention. NAC (N-acetylcysteine) is antidote. Do not delay. |
| Parameter | Information |
|---|---|
| Toxic Dose | > 150 mg/kg (or > 10 g total in adults) |
| Mechanism | Glutathione depletion; accumulation of NAPQI |
| Symptoms | Nausea, vomiting, anorexia (first 24h); then right upper quadrant pain, jaundice, liver failure |
| Treatment | N-Acetylcysteine (NAC) IV or oral |
| Time Window | Most effective within 8-10 hours of ingestion |
| Prognosis | Excellent with early treatment; may require liver transplant in severe cases |
| Parameter | Information |
|---|---|
| Biodegradability | Readily biodegradable (inherently) |
| Aquatic Toxicity | Low to moderate toxicity |
| Bioaccumulation | Not expected |
| Waste Disposal | Dispose according to local regulations (pharmaceutical waste) |
| Parameter | Information |
|---|---|
| UN Number | Not regulated (non-hazardous) |
| Hazard Class | None |
| Packing Group | Not applicable |
| Region | Status |
|---|---|
| EU | Approved medicinal substance; OTC availability |
| USA (FDA) | Approved OTC (over-the-counter) drug |
| Turkey | Approved OTC and prescription drug |
| UK (MHRA) | Approved OTC and POM for combination products |
| Canada (Health Canada) | Approved OTC drug |
| WHO | Included in WHO Essential Medicines List |
Prescription Status:
OTC: Single ingredient (500 mg)
Prescription: Some high-strength or combination products (with codeine)
| Turkish Name | English Name |
|---|---|
| Parasetamol | Paracetamol |
| Asetaminofen | Acetaminophen |
| APAP | APAP |
| N-(4-hidroksifenil)asetamid | N-(4-hydroxyphenyl)acetamide |
| 4-Asetamidofenol | 4-Acetamidophenol |
Trade Names (Partial List):
Tylenol® (USA)
Panadol® (Global)
Calpol® (Pediatric)
Ultramol (UK)
Various generics
Paracetamol (Acetaminophen / APAP, CAS 103-90-2) is the most widely used analgesic (pain reliever) and antipyretic (fever reducer) medication worldwide. It is a para-aminophenol derivative that acts primarily as a selective COX-2 inhibitor in the central nervous system.
Key Features:
| Feature | Description |
|---|---|
| Appearance | White crystalline powder |
| Molecular Weight | 151.16 g/mol |
| Melting Point | 168-172 °C |
| Solubility | Sparingly soluble in water; freely soluble in ethanol |
Main Therapeutic Applications:
| Use | Indication |
|---|---|
| Analgesic | Mild to moderate acute pain (headache, toothache, dysmenorrhea, post-operative) |
| Antipyretic | Fever reduction |
| Combination Products | With codeine, caffeine for enhanced effect |
Key Safety Points:
WELL-TOLERATED – Minimal GI effects, no antiplatelet activity
HEPATOTOXICITY RISK – Overdose can cause severe liver damage
MAXIMUM DAILY DOSE – 4000 mg (adults)
ANTIDOTE – N-Acetylcysteine (NAC) for overdose
WIDELY AVAILABLE – OTC in most countries
Mechanism Clarification: Unlike traditional NSAIDs, paracetamol has minimal peripheral anti-inflammatory effects. Its primary action is central (CNS) COX-2 inhibition.
Overdose Danger: Paracetamol overdose is a leading cause of acute liver failure. The maximum daily adult dose is 4000 mg. Never exceed recommended doses.
Hepatotoxicity Mechanism: At therapeutic doses, the toxic metabolite NAPQI is detoxified by glutathione. Overdose depletes glutathione, causing NAPQI accumulation and hepatocyte necrosis.
Combination Products: Many OTC cold/flu and prescription pain medications contain paracetamol. Patients must avoid double-dosing from multiple products.
Purity Critical Parameter: 4-Aminophenol is a toxic impurity and degradation product. Pharmacopeial limits require ≤ 50 ppm. High-quality pharmaceutical grade is essential.
Stability: Protect from light to prevent discoloration (oxidation). Discolored product should not be used.
Codeine Combinations: Paracetamol + codeine combinations are controlled substances in many countries (opioid component).
Pediatric Dosing: Dosing is weight-based (10-15 mg/kg). Infant formulations (suspension) are available. Never exceed recommended pediatric doses.
Alcohol Interaction: Chronic alcohol use may increase hepatotoxicity risk at therapeutic doses due to glutathione depletion.
Regulatory Status: While single-ingredient paracetamol is OTC worldwide, some combination products require prescription (e.g., with codeine).
Important Disclaimer: This Technical Data Sheet (TDS) is for informational purposes only. For complete safety, handling, storage, and regulatory compliance information, always refer to the official Safety Data Sheet (SDS) and product information provided by the manufacturer/supplier. This document is not a substitute for medical advice. Paracetamol should be used according to medical guidance. Overdose is a medical emergency.