Comparative plasma concentration profiles after i.v., i.m. and rectal administration of pethidine in children.
Plasma concentration-time curves of pethidine and norpethidine were studied in 25 children allocated after operation to three groups to receive pethidine 1 mg kg-1 i.v., i.m. or rectally. Peak concentrations occurred after 5 +/- 1, 10 +/- 2, and 60 +/- 10 min, respectively, while the maximum concentrations amounted to 2800 +/- 462, 1609 +/- 367 and 531 +/- 179 nmol litre-1, respectively. The area under the curve (0-240 min) was similarly reduced in the group with rectal administration (P less than 0.05). Compared with the i.v. data, approximately 40% systemic availability occurred after rectal application, although considerable individual variation was noted. In one child very high plasma concentrations were observed after rectal administration, possibly as a result of redistribution/recirculation phenomena. The average results are similar to those obtained when other opioids are given rectally.
Jacobsen
J
J
Department of Anaesthesia, University of Copenhagen, Rigshospitalet, Denmark.
Flachs
H
H
Dich-Nielsen
J O
JO
Rosen
J
J
Larsen
A B
AB
Hvidberg
E F
EF
D000285:Administration, Rectal; D000293:Adolescent; D002648:Child; D002800:Cholinesterase Inhibitors / Q000097:blood; D006801:Humans; D007273:Injections, Intramuscular; D007275:Injections, Intravenous; D008614:Meperidine / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000097:blood*; D013997:Time Factors
D002800:Cholinesterase Inhibitors; D008614:Meperidine; C002752:normeperidine