Paracetamol Suppository Dosing
For adults, use paracetamol suppositories at 650-1000 mg every 4-6 hours, not exceeding 4000 mg per day, though a more conservative maximum of 3000 mg daily is recommended for chronic use. 1, 2
Adult Dosing
- Standard dose: 650-1000 mg rectally every 4-6 hours 1, 2
- Maximum daily dose: 4000 mg in 24 hours 1, 3, 2
- Conservative maximum for chronic use: 3000 mg per day to reduce hepatotoxicity risk 1, 2
- Minimum interval between doses: 4 hours 1
- Maximum number of doses: 6 doses in 24 hours 1
The rectal route has identical hepatotoxicity risk as oral administration because the liver processes all systemically absorbed paracetamol identically via cytochrome P450 enzymes, producing the toxic metabolite NAPQI when glutathione stores are depleted. 2
Pediatric Dosing
- Loading dose: 20-40 mg/kg rectally (15 mg/kg if weight <10 kg) due to poor bioavailability from the rectal route 2
- Maintenance dose: 10-15 mg/kg every 4-6 hours 2
- Maximum daily dose: 60 mg/kg/day 2
- For children ≥12 years: 650 mg every 4-6 hours, maximum 6 doses in 24 hours, not exceeding 4000 mg total daily 1
The higher loading dose for rectal administration compensates for the reduced bioavailability compared to oral or intravenous routes. 2
Special Populations Requiring Dose Reduction
Elderly Patients (≥60 years)
- Maximum daily dose: 3000 mg or less 1, 3
- Starting dose: 650 mg every 4-6 hours rather than 1000 mg 2
- No evidence supports routine dose reduction for all older people, but frail elderly should start at lower doses 4, 5
Liver Disease
- Maximum daily dose: 2000-3000 mg per day 1, 2
- Patients with cirrhosis can safely use 2-3 g/day long-term without causing decompensation 2
- Monitor liver enzymes closely 2
Chronic Alcohol Users
- Maximum daily dose: 2000-3000 mg per day 1, 2
- Advise to avoid concurrent alcohol use 1
- Even chronic alcohol users with cirrhosis can consume up to 3 g daily without increased decompensation risk 2
Critical Safety Warnings
Repeated supratherapeutic ingestions (doses just above therapeutic range) carry a worse prognosis than acute single overdoses, with approximately 30% of overdose admissions involving repeated supratherapeutic use. 1, 2
Common Pitfalls to Avoid
- Failing to recognize paracetamol in combination products (over-the-counter cold remedies, sleep aids, opioid combinations) leads to unintentional overdose 1, 2
- Using multiple paracetamol-containing products simultaneously without tracking total daily intake 1, 2
- Not adjusting dosage for patients with liver disease or chronic alcohol use 2
- Prescription combination products are limited to ≤325 mg paracetamol per dosage unit per FDA recommendations 1, 2
Explicit Patient Counseling Required
When prescribing up to 4000 mg/day, explicitly counsel patients to avoid all other paracetamol-containing products, including over-the-counter medications and prescription combinations. 1, 2
Route-Specific Considerations
The rectal route is appropriate when oral administration is unreliable due to nausea, vomiting, postoperative ileus, altered gastric emptying, or impaired intestinal transit. 2 However, rectal bioavailability is lower than oral, necessitating higher loading doses in pediatric patients. 2