1% w/v PARACETAMOL Infusion/Solution for

What is 1% w/v PARACETAMOL

1% w/v Paracetamol Injection is a sterile, non-pyrogenic solution of paracetamol, designed for intravenous (IV) administration. It is commonly used for the treatment of mild to moderate pain and fever, especially in cases where oral administration is not possible or practical. This formulation is particularly beneficial in hospital settings for postoperative pain, high fevers, or in patients who cannot swallow tablets or tolerate oral medications.

• Active Ingredient: Paracetamol (also known as acetaminophen) 1% w/v
• Form: IV solution in 100 ml plastic bag
• Route: Intravenous infusion only
• Indications: Short-term treatment of moderate pain, and fever, often used in surgical or emergency care

This injectable formulation offers rapid onset of action and is frequently used when prompt pain or fever management is necessary. It can be used alone or as an adjunct to opioid analgesics to reduce the required dose of opioids.

How to use 1% w/v PARACETAMOL

The administration of 1% w/v Paracetamol Injection should always be performed by qualified healthcare professionals in a hospital or clinical setting. It is typically infused over a 15-minute period using a standard IV set.

• Dosage and infusion: Administer slowly over 15 minutes to reduce infusion-related reactions.
• Adult use: Usually, a single dose of 1000 mg (i.e., 100 ml of 1% solution) is administered every 6 hours as needed. Do not exceed 4 g per day.
• Children: Dose must be calculated based on body weight (15 mg/kg per dose), and medical supervision is essential.
• Inspection: Always inspect the solution before use. Do not use if discolored or contains particulates.

Do not mix with other medicinal products in the same infusion line unless compatibility is known. The IV line should be flushed before and after the infusion to ensure complete delivery of the drug.

Mode of Action 1% w/v PARACETAMOL

Paracetamol is a centrally acting analgesic and antipyretic. Though its exact mechanism is not fully understood, several pharmacological actions explain its clinical efficacy.

• Central Inhibition of Prostaglandin Synthesis: Paracetamol inhibits cyclooxygenase (COX) enzymes, particularly COX-2, in the brain, leading to reduced synthesis of prostaglandins, which are key mediators of pain and fever.
• Antipyretic Effect: It acts on the hypothalamic heat-regulating center, promoting peripheral vasodilation and increased heat dissipation.
• Minimal Anti-inflammatory Action: Unlike NSAIDs, paracetamol has limited peripheral anti-inflammatory activity, making it ideal for patients with GI risks or NSAID sensitivity.
• No Platelet or Gastric Activity: Paracetamol does not significantly affect platelet aggregation or gastric mucosa, making it safer for long-term or postoperative use compared to NSAIDs.

Overall, its selective action in the central nervous system provides effective analgesia and antipyresis without many of the adverse effects associated with other analgesics like NSAIDs or opioids.

1% w/v PARACETAMOL Interactions 1% w/v PARACETAMOL

While paracetamol is generally well-tolerated, it can interact with several other drugs, particularly those metabolized by the liver. Co-administration with certain medications may alter therapeutic effects or increase the risk of toxicity.

• Warfarin and other anticoagulants: Prolonged use of paracetamol can enhance the effect of warfarin, increasing the risk of bleeding. Monitor INR levels if used concurrently.
• Enzyme-inducing drugs (e.g., phenytoin, carbamazepine, rifampin): These may increase the hepatotoxic potential of paracetamol by promoting its conversion to toxic metabolites.
• Alcohol: Chronic alcohol consumption may reduce liver capacity to metabolize paracetamol safely, raising the risk of hepatotoxicity.
• Cholestyramine: May reduce the absorption and effect of paracetamol when given concomitantly.
• Metoclopramide and domperidone: These can accelerate paracetamol absorption and onset of action.

Always inform healthcare providers of all medications being taken to avoid potential interactions.

Dosage of 1% w/v PARACETAMOL

The correct dosage of 1% w/v Paracetamol Injection depends on patient age, weight, and clinical condition. Adhering to maximum daily limits is essential to avoid liver toxicity.

• Adults and adolescents (>50 kg): 1000 mg every 6 hours (maximum 4 g/day)
• Adults and adolescents (<50 kg): 15 mg/kg every 4–6 hours (maximum 60 mg/kg/day, not exceeding 3 g/day)
• Children (10–50 kg): 15 mg/kg per dose, not more than 60 mg/kg/day in divided doses
• Neonates and infants: Use only under specialist supervision, as metabolic clearance is slower

Doses must be spaced at least 4 hours apart. Adjustments are needed in patients with hepatic impairment, malnutrition, or chronic alcohol use. Always follow institutional or manufacturer’s guidelines.

Possible side effects of 1% w/v PARACETAMOL

Paracetamol IV is generally well-tolerated, but adverse effects can occur, especially with overdose or prolonged use. Side effects are usually mild and self-limiting but may become serious in rare cases.

• Common side effects:
  • Headache
  • Nausea
  • Vomiting
  • Injection site pain or erythema
• Uncommon side effects:
  • Increased liver enzymes (ALT, AST)
  • Hypotension (especially with rapid infusion)
• Rare but serious:
  • Hypersensitivity reactions (rash, angioedema)
  • Severe liver damage in overdose
  • Thrombocytopenia (low platelets)

Seek immediate medical help in case of signs of allergic reactions, such as swelling of face or difficulty breathing. Regular monitoring of liver function is advised in long-term use.

1% w/v PARACETAMOL Contraindications 1% w/v PARACETAMOL

While generally safe, certain conditions contraindicate the use of intravenous paracetamol. Administration should be avoided or closely monitored under the following circumstances:

• Known hypersensitivity to paracetamol or any excipients in the formulation
• Severe hepatic impairment or liver failure due to increased risk of hepatotoxicity
• Glucose-6-phosphate dehydrogenase deficiency — may increase oxidative stress risk
• Severe renal impairment — accumulation of metabolites may occur
• Alcoholic liver disease — chronic alcohol use increases the risk of liver damage even at therapeutic doses

Use with caution in malnourished patients, the elderly, and those with low body weight, as they are at increased risk of hepatic injury even within standard dosing ranges.

Storage of 1% w/v PARACETAMOL

Proper storage of 1% w/v Paracetamol Injection is essential to maintain its efficacy and safety. The solution should be protected from light and stored in accordance with the manufacturer’s instructions.

• Temperature: Store below 25°C. Do not freeze.
• Light protection: Keep in original overwrap to protect from light until ready to use.
• Single-use only: Once opened, the solution must be used immediately. Discard any unused portion.
• Container integrity: Do not use if the plastic bag is damaged, discolored, or if visible particles are present.
• Shelf life: Refer to product packaging for expiry date. Do not use after expiry date.

Ensure the infusion is administered using sterile techniques in a clinical environment. Proper storage reduces the risk of contamination and preserves drug stability.