Usage
- Medical Conditions: Lidocaine + Paracetamol is prescribed for the short-term management of moderate to severe pain, particularly post-operative pain and pain associated with neoplasms. It may also be used to treat fever associated with infection or neoplasms.
- Pharmacological Classification: Analgesic (Paracetamol), local anesthetic (Lidocaine).
- Mechanism of Action: Paracetamol provides systemic analgesia and antipyresis through central inhibition of prostaglandin synthesis. Lidocaine provides local anesthetic action by blocking sodium channels, thereby inhibiting nerve impulse transmission.
Alternate Names
- While “Lidocaine + Paracetamol” is the common generic name, regional variations may exist.
- Brand Name: Apotel Plus®
How It Works
- Pharmacodynamics: Paracetamol’s analgesic and antipyretic effects are mediated centrally, primarily through cyclooxygenase (COX) enzyme inhibition, especially COX-3 within the central nervous system. Lidocaine blocks voltage-gated sodium channels in neuronal membranes. By binding to these channels, it blocks action potential propagation, reducing neural excitability. This leads to a localized loss of sensation.
- Pharmacokinetics: Paracetamol is rapidly absorbed after intramuscular administration and is metabolized primarily by the liver via conjugation with glucuronide and sulfate. Lidocaine is also absorbed well intramuscularly and is metabolized primarily in the liver by CYP enzymes. Both are mainly eliminated in the urine.
- Elimination Pathways: Primarily renal excretion for both drugs.
Dosage
Standard Dosage
Adults:
- 1 ampoule (600mg Paracetamol + 20mg Lidocaine Hydrochloride) intramuscularly 3-4 times daily.
- Maintain a minimum 4-hour interval between doses.
- Maximum daily dose: 5 ampoules.
Children:
- Over 12 years: 1 ampoule 3-4 times daily, intramuscularly.
- 6-12 years: ½ - 1 ampoule 3-4 times daily, intramuscularly.
- 1-6 years: ¼ - ⅓ ampoule (or 10 mg/kg) 3-4 times daily, intramuscularly.
- Pediatric safety should be assessed by a medical professional on a case-by-case basis due to the potential risk of methemoglobinemia and immature metabolic pathways.
Special Cases:
- Elderly Patients: Due to potential age-related decline in hepatic and renal function, dosage adjustments may be required. Close monitoring is recommended.
- Patients with Renal Impairment: In acute renal failure (creatinine clearance <10 mL/min), the interval between doses should be increased to 8 hours.
- Patients with Hepatic Dysfunction: Dose adjustment is necessary due to reduced Paracetamol metabolism. Close monitoring is essential.
- Patients with Comorbid Conditions: Consider conditions like heart failure and malnutrition when dosing.
Clinical Use Cases
- This combination, specifically Apotel Plus®, is indicated for post-surgical pain management and cancer-related pain according to the source material provided. It’s not typically used for procedures like intubation, mechanical ventilation, or in specific ICU/emergency situations. Other forms of Lidocaine, without Paracetamol, are commonly used in those contexts.
Dosage Adjustments
- Dosage adjustments should be based on patient-specific factors such as renal and hepatic function, age, and other comorbid conditions.
Side Effects
Common Side Effects
- Paracetamol: Generally well-tolerated; rare cases of hypersensitivity reactions.
- Lidocaine: Dizziness, confusion.
Rare but Serious Side Effects
- Paracetamol: Hepatotoxicity (with overdose).
- Lidocaine: Seizures, respiratory depression, cardiac arrhythmias (with overdose).
Long-Term Effects
- Paracetamol: Potential nephrotoxicity with prolonged high doses.
- Lidocaine: Generally not indicated for long-term use.
Adverse Drug Reactions (ADR)
- Methemoglobinemia, especially in susceptible populations (neonates, infants, patients with cardiac/pulmonary disease, G6PD deficiency).
- Hypersensitivity reactions.
Contraindications
- Hypersensitivity to paracetamol, lidocaine, or any excipients.
- Pregnancy (due to the excipient Glycerol Formal in Apotel Plus®).
- Severe hepatic or renal insufficiency.
- Concomitant use of antiarrhythmic medications.
Drug Interactions
- Paracetamol: Cholestyramine (decreased absorption), Metoclopramide/Domperidone (increased absorption), hepatic enzyme inducers (increased risk of hepatotoxicity), anticoagulants (increased risk of bleeding), Lamotrigine (decreased bioavailability), Alcohol with overdose (increased hepatotoxicity).
- Lidocaine: Cimetidine, Propranolol (increased serum levels).
Pregnancy and Breastfeeding
- Pregnancy: Contraindicated due to teratogenic potential of Glycerol Formal.
- Breastfeeding: Paracetamol is excreted in breast milk but is generally considered compatible with breastfeeding. Lidocaine is also excreted in breast milk, and caution should be exercised.
Drug Profile Summary
- Mechanism of Action: Paracetamol: Central COX inhibition; Lidocaine: Sodium channel blockade.
- Side Effects: Common: Dizziness, confusion. Serious: Hepatotoxicity (Paracetamol overdose), seizures, respiratory depression (Lidocaine overdose), methemoglobinemia.
- Contraindications: Hypersensitivity, pregnancy, severe hepatic/renal impairment.
- Drug Interactions: See detailed section above.
- Pregnancy & Breastfeeding: Contraindicated in pregnancy. Caution during breastfeeding.
- Dosage: See detailed section above.
- Monitoring Parameters: Liver function tests (especially with long-term Paracetamol use), renal function, signs of methemoglobinemia.
Popular Combinations
- Not applicable for this specific formulation (Apotel Plus®) as it is a fixed-dose combination designed to address pain and fever.
Precautions
- Pre-screening for allergies, hepatic and renal function, and cardiac conditions.
- Avoid use in pregnancy. Caution during breastfeeding.
- Use caution in children due to increased susceptibility to methemoglobinemia.
- Monitor for side effects, especially in susceptible individuals.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Lidocaine + Paracetamol (Apotel Plus®)?
A: Adults: 1 ampoule IM 3-4 times/day; Children (over 12 yrs): 1 ampoule IM 3-4 times/day; Children (6-12 yrs): ½ -1 ampoule IM 3-4 times/day; Children (1-6 yrs): ¼ - ⅓ ampoule IM (or 10mg/kg) 3-4 times/day.
Q2: Can Lidocaine + Paracetamol be administered intravenously?
A: No, Apotel Plus® is strictly for intramuscular administration. Intravenous administration is contraindicated.
Q3: Is Lidocaine + Paracetamol safe to use during pregnancy?
A: No, Apotel Plus® is contraindicated during pregnancy due to the presence of Glycerol Formal.
Q4: What are the signs of Lidocaine toxicity?
A: Signs of Lidocaine toxicity can include seizures, respiratory depression, cardiovascular collapse, altered mental status and cardiac arrhythmias.
Q5: What is the maximum daily dose of Paracetamol in this combination?
A: The maximum daily dose is 3000mg of paracetamol, which corresponds to 5 ampoules of Apotel Plus®.
Q6: What are the common side effects of Lidocaine + Paracetamol?
A: Common side effects may include dizziness, confusion.
Q7: How should the dosage be adjusted for patients with renal impairment?
A: For patients with acute renal failure (creatinine clearance <10 mL/min), increase the dosing interval to 8 hours.
Q8: What are the key drug interactions to be aware of?
A: Key drug interactions include those with cimetidine, propranolol, cholestyramine, metoclopramide, hepatic enzyme inducers, anticoagulants, and lamotrigine. Concurrent use of alcohol with a paracetamol overdose should be avoided.
Q9: Can Lidocaine + Paracetamol be used in patients with liver disease?
A: Use with extreme caution in patients with hepatic dysfunction. Dose adjustment and close monitoring are essential due to impaired paracetamol metabolism. Contraindicated in severe liver impairment.
Q10: How should I monitor patients receiving Lidocaine + Paracetamol?
A: Monitor patients for side effects, especially signs of methemoglobinemia. Liver and renal function tests should be performed, particularly with long-term paracetamol use.
