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.

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.

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