Escitalopram as a Treatment for Pain in Polyneuropathy

Condition(s) targeted: Pain; Polyneuropathies

Intervention: escitalopram (Drug)

Phase: Phase 4

Status: Completed

Sponsored by: Odense University Hospital

Official(s) and/or principal investigator(s):
Soeren H Sindrup, MD, PhD, Principal Investigator, Affiliation: Odense University Hospital, Dept. of neurology

Many people with polyneuropathy suffer from pain which is difficult to treat. Escitalopram is a relatively new drug used in the treatment of depression. Escitalopram’s action mechanism on the brain suggests that escitalopram also may have an effect on neuropathic pain. This study will test the efficacy of escitalopram in patients with painful polyneuropathy.

Official title: Escitalopram as a Treatment for Pain in Polyneuropathy. A Double-Blind, Randomized, Placebo Controlled Trial.

Study design: Treatment, Randomized, Double-Blind, Placebo Control, Crossover Assignment, Efficacy Study

Primary outcome: pain relief

Secondary outcome:

effect on total pain and different subtypes of pain

effect on quantitative sensory testing

effect on pain related sleep disturbances

effect on quality of life

to determine if depression before treatment predicts an eventual pain relieving effect of escitalopram

Detailed description: Tricyclic antidepressants appear to be the most efficacious treatment of painful polyneuropathy. However, these drugs are contraindicated in some patients and a substantial number of patients decline treatment due to side-effects. Therefore, effective drugs that are better tolerated are needed. Clinical and basic research has demonstrated that drugs with serotonergic action can alleviate neuropathic pain. Escitalopram increases serotonin concentration in the central nervous system, suggesting that it might be a potential alternative to current treatments of neuropathic pain. The aim of this study is to test if escitalopram would relieve painful polyneuropathy.

Comparisons: Treatment with 20 mg escitalopram daily will be compared in a cross-over design with placebo. Each treatment period will last 6 weeks. During the last week of each treatment period, the dose will be tapered.

Minimum age: 20 Years. Maximum age: 80 Years. Gender(s): Both.

Criteria:

Inclusion Criteria:

- median total pain score at baseline week >=4 on a 10 point numerical rating scale

- characteristic symptoms of polyneuropathy within at least 6 months

- diagnosis confirmed by physical examination, neurophysiologic exam. and/or

quantitative sensory testing

- pain at least 4 of 7 days

- fertile women are using anticonceptive

Exclusion Criteria:

- other cause to pain than polyneuropathy

- former allergic reactions on escitalopram

- known adverse events on escitalopram

- pregnancy or nursing

- critical disease (terminal cancer, cardial incompensation or critical renal or lung

disease)

- treatment with monoamine oxidase inhibitors between the trial or 2 weeks before or

after treatment with other antidepressants, antiepileptic agents or opioids

Dept. of Neurology, Odense University Hospital, Sdr. Boulevard 29, Odense 5000, Denmark

Danish Pain Research Center, Aarhus University Hospital, Noerrebrogade 44, Aarhus 8000, Denmark

Related publications:

Burke WJ. Escitalopram. Expert Opin Investig Drugs. 2002 Oct;11(10):1477-86. Review.

Sindrup SH, Jensen TS. Pharmacologic treatment of pain in polyneuropathy. Neurology. 2000 Oct 10;55(7):915-20. Review.

Woolf CJ, Mannion RJ. Neuropathic pain: aetiology, symptoms, mechanisms, and management. Lancet. 1999 Jun 5;353(9168):1959-64. Review.

Mork A, Kreilgaard M, Sanchez C. The R-enantiomer of citalopram counteracts escitalopram-induced increase in extracellular 5-HT in the frontal cortex of freely moving rats. Neuropharmacology. 2003 Aug;45(2):167-73.

Starting date: December 2004
Ending date: April 2007
Last updated: April 23, 2007