The effects of imipramine, amitriptyline and clonidine administered by iontophoresis on the pain threshold.
We performed iontophoresis of aqueous solution of imipramine and amitriptyline, tricyclic antidepressant, and clonidine, an alpha 2 agonist, in a total of 30 healthy adult volunteers. Analgesic effects were compared among the 3 drugs by measurement of the pain threshold using a thermopainmeter. No significant changes in the pain threshold were observed with imipramine or amitriptyline. On the other hand, clonidine significantly increased the pain threshold, compared with the control value before iontophoresis. Although the effects of iontophoresis of clonidine were smaller than the previously reported effects of iontophoresis with other drugs, these effects seemed to be due to the action of clonidine itself not associated with electric stimulation. More marked effects may be obtained with changes in the conditions of iontophoresis.
Taniguchi
K
K
Department of Anesthesiology, Oita Medical University, Japan.
Yoshitake
S
S
Iwasaka
H
H
Honda
N
N
Oyama
T
T
D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage*; D000328:Adult; D000639:Amitriptyline / Q000008:administration & dosage / Q000494:pharmacology*; D000929:Antidepressive Agents, Tricyclic / Q000008:administration & dosage / Q000494:pharmacology*; D003000:Clonidine / Q000008:administration & dosage*; D006801:Humans; D007099:Imipramine / Q000008:administration & dosage / Q000494:pharmacology*; D007478:Iontophoresis; D010146:Pain / Q000517:prevention & control*; D012684:Sensory Thresholds / Q000187:drug effects
D000316:Adrenergic alpha-Agonists; D000929:Antidepressive Agents, Tricyclic; D000639:Amitriptyline; D003000:Clonidine; D007099:Imipramine