Oral paracetamol(acetaminophen) is no better than rectal paracetamol in lowering fever

Date First Published:
December 9, 2008
Last Updated:
October 17, 2011
Report by:
Tang Man Chun, Scott, Undergraduate, Mb ChB Programme (The Chinese University of Hong Kong)
Search checked by:
Giles Cattermole, The Chinese University of Hong Kong
Three-Part Question:
In [patients with fever], is [oral paracetamol(acetaminophen) or rectal paracetamol] more effective [in lowering the body temperature]?
Clinical Scenario:
A 1-year-old boy presented to emergency department with fever. History and Physical examination suggested upper respiratory tract infection. You want to prescribe paracetamol(acetaminophen) for the fever, but the boy kept on crying and oral route was not possible. You wonder if oral route is more effective than rectal administration.
Search Strategy:
Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations, Ovid MEDLINE(R) Daily and Ovid MEDLINE(R) 1950 to Present
Date of Search: 17-Dec-2008
#1 : tAcetaminophen.mp. or exp Acetaminophen/
#2 : tparacetamol.mp. [mp=title, original title, abstract, name of substance word, subject heading word]
#3 : t1 or 2
#4 : texp Administration, Oral/ or oral.mp.
#5 : texp Tablets/
#6 : texp Administration, Rectal/
#7 : trect*.mp.
#8 : texp Suppositories/
#9 : t(4 or 5) and (6 or 7 or 8)
#10 : texp Body Temperature/ or exp Temperature/
#11 : texp Fever/
#12 : tantipyretic.mp. [mp=title, original title, abstract, name of substance word, subject heading word]
#13 : t10 or 11 or 12
#14 : t3 and 9 and 13
#15 : tlimit 14 to (english language and humans)
Search Details:
A recent meta-analysis(See Below) addressed the clinical question but was not included in the search as it had not been indexed by the date of searching and could not be found in Ovid Medline.
Meta-analysis: Goldstein LH, Berlin M, Berkovitch M, Kozer E. Effectiveness of Oral vs Rectal Acetaminophen. A Meta-analysis. Archives of Pediatrics & Adolescent Medicine NOV 2008, VOL 162 (NO. 11)
Outcome:
30 papers were found and 5 papers were relevant. Four were clinical trials and the remaining one was a cohort study.
Relevant Paper(s):
Study Title Patient Group Study type (level of evidence) Outcomes Key results Study Weaknesses
Equal antipyretic effectiveness of oral and rectal acetaminophen: a randomized controlled trial Nabulsi M. Tamim H. Sabra R. Mahfoud Z. Malaeb S. Fakih H. Mikati M. 2005 Lebanon 51 febrile children aged 6 months to 13 years old This is a randomized, double-dummy, double-blind study. Time to maximum antipyresis No significant difference among the three groups Sample size is 51 only.
Tme to fever reduction by 1 degrees C No significant difference among the three groups
Antipyretic therapy. Comparison of rectal and oral paracetamol. Keinanen S. Hietula M. Simila S. Kouvalainen K. 1977 Aug GERMANY, WEST 30 children between the age of 4 months and 12 years, who had infections and a rectal temperature above 38.5 degrees C Cohort study Maximum fall of temperature Oral form is more effective(maximum fall of temperature 1.58 degrees C) then rectal(maximum fall of temperature 1.24 degrees C) The study is not randomized. the sample size is small
Comparison of oral versus normal and high-dose rectal acetaminophen in the treatment of febrile children. Scolnik D. Kozer E. Jacobson S. Diamond S. Young NL. 2002 Sep Canada 70 patients aged 6 months to 6 years with fever > or =39 degrees C A randomized, controlled trial. Temperature change at 3 hours No significant difference between the two groups Sample size is small. Study period is only 3 hour.
Maximum drop in temperature or final temperature No significant difference between the two groups
Rectal paracetamol in small children with fever. Vernon S, Bacon C, Weightman D 1979 Jun 37 febrile children aged between 3 months and 6 years Randomized Controlled Trial Antipyretic effect Oral route and rectal route have the same effect. Sample size is small. the results are not in details.
The antipyretic effectiveness of acetaminophen suppositories versus tablets: a double-blind study. Maron JJ, Ickes AC 1976 Jul 83 patients with age 23 to 96 years old Randomized, double-dummy, controlled trial Decline in temperature at 1 hour No difference between two groups The age range of subjects are too wide.
Decline in temperature at 3 hours No difference between two groups
Author Commentary:
Four out of 5 study suggested that the effectiveness of rectal paracetamol is comparable with oral route with respect to temperature reduction. A recent meta-analysis which included the four randomized trials(1.tGoldstein LH, Berlin M, Berkovitch M, Kozer E. Effectiveness of Oral vs Rectal Acetaminophen. A Meta-analysis Archives of Pediatrics & Adolescent Medicine NOV 2008, VOL 162 (NO. 11)) also showed the same result. The only study which showed opposite result was not randomized and had a small sample size. Further studies are needed to evaluate the toxicity between the two routes of paracetamol administration.
Bottom Line:
Rectal paracetamol have same anti-pyretic effect as oral form and can be given as an alternative in patients who are not able to take oral form.
References:
  1. Nabulsi M. Tamim H. Sabra R. Mahfoud Z. Malaeb S. Fakih H. Mikati M.. Equal antipyretic effectiveness of oral and rectal acetaminophen: a randomized controlled trial
  2. Keinanen S. Hietula M. Simila S. Kouvalainen K.. Antipyretic therapy. Comparison of rectal and oral paracetamol.
  3. Scolnik D. Kozer E. Jacobson S. Diamond S. Young NL.. Comparison of oral versus normal and high-dose rectal acetaminophen in the treatment of febrile children.
  4. Vernon S, Bacon C, Weightman D. Rectal paracetamol in small children with fever.
  5. Maron JJ, Ickes AC. The antipyretic effectiveness of acetaminophen suppositories versus tablets: a double-blind study.