Escitalopram in painful polyneuropathy: a randomized, placebo-controlled, cross-over trial.
Serotonin (5-HT) is involved in pain modulation via descending pathways in the central nervous system. The aim of this study was to test if escitalopram, a selective serotonin reuptake inhibitor (SSRI), would relieve pain in polyneuropathy. The study design was a randomized, double-blind, placebo-controlled cross-over trial. The daily dose of escitalopram was 20mg once daily. During the two treatment periods of 5 weeks duration, patients rated pain relief (primary outcome variable) on a 6-point ordered nominal scale. Secondary outcome measures comprised total pain and different pain symptoms (touch- or pressure-evoked pain, lancinating pain, constant burning or deep aching pain) by the use of 0-10-point numeric rating scales. Changes in health-related quality of life and severity of depression were measured with the SF-36 and the Major Depression Inventory (MDI). Forty-one patients were included in the data analysis. Patients reported a better pain relief during treatment with escitalopram compared with placebo (p=0.001). Total pain and different pain symptoms were lower during escitalopram treatment (p=0.001-0.024). The Number needed to treat (NNT) to obtain one patient with good or complete pain relief was 6.8. Health-related quality of life and depressive symptoms were unaltered (p=0.086-1.0). Five patients (10.4%) discontinued the study because of adverse effects during escitalopram. This study found a pain-relieving effect of escitalopram in patients with painful polyneuropathy, but a clinically relevant effect was obtained in only few patients. Currently, the drug cannot be recommended as a standard treatment in neuropathic pain.
Department of Neurology, Odense University Hospital, University of Southern Denmark, Sdr. Boulevard 29, 5000 Odense C, Denmark Department of Neurology, Aalborg Sygehus, Aarhus University Hospital, Denmark Danish Pain Research Center, Aarhus University Hospital, University of Aarhus, Denmark Institute of Public Health, Department of Clinical Pharmacology, University of Southern Denmark, Odense, Denmark.
Marit
M
Otto
Flemming W
FW
Bach
Troels S
TS
Jensen
Kim
K
Brøsen
Søren H
SH
Sindrup
D000328:Adult; D000368:Aged; D015283:Citalopram / Q000627:therapeutic use*; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000175:diagnosis* / Q000188:drug therapy*; D010147:Pain Measurement / Q000187:drug effects*; D015990:Placebo Effect; D011115:Polyneuropathies / Q000175:diagnosis* / Q000188:drug therapy*; D012702:Serotonin Antagonists / Q000627:therapeutic use; D016896:Treatment Outcome
D012702:Serotonin Antagonists; D015283:Citalopram