Relationship between plasma concentration levels of risperidone and clinical effects in the treatment of delirium.
The present study aimed to examine the relationship between plasma concentration levels of risperidone and clinical effects in the treatment of delirium. We conducted a prospective, open-label, flexible-dose study of risperidone oral solution. Ten patients with delirium were assessed using Delirium Rating Scales. Plasma concentration levels of risperidone were measured 30 min after the first administration of a 0.5 mg dose. Two patients with high plasma levels had adverse effects and one patient with the lowest plasma level did not achieve remission; the remaining seven patients achieved remission without any adverse effects. A highly significant negative correlation was observed in these responders without adverse effects between the plasma levels and durations of treatment until remission (r=-0.861, P=0.0095). The plasma concentration level of risperidone at 30 min after the first 0.5 mg dose may be a favourable response predictor in the treatment of delirium. Further studies in larger samples are needed to verify this preliminary finding.
Toda
Hiroyuki
H
Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
Kusumi
Ichiro
I
Sasaki
Yukiya
Y
Ito
Koichi
K
Koyama
Tsukasa
T
D000284:Administration, Oral; D000368:Aged; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D003693:Delirium / Q000097:blood / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D018967:Risperidone / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D013997:Time Factors
D014150:Antipsychotic Agents; D018967:Risperidone