Pharmacological Management of Central Neuropathic Pain

Introduction

Central neuropathic pain (central pain) is found in different neuropathic pain conditions as a direct consequence of a lesion or disease affecting the central somatosensory system 1. It may be a consequence of stroke (central poststroke pain, CPSP), spinal cord injury (SCI), multiple sclerosis (MS), traumatic brain injury, and other conditions affecting the central nervous system (CNS). The prevalence of central pain is highest following SCI, where it affects 40–50% 2–4, while about 25% of patients with MS 5, and around 8–10% of patients after a stroke 6 (Klit et al., unpublished observation) experience central pain. Sensory abnormalities associated with CNS lesions range from paresthesia (abnormal sensations that are not painful or unpleasant) over dysesthesia (unpleasant abnormal sensations) 7 to mild or severe pain. In some patients, central pain is ranked as the most disabling consequence of their disease, severely interfering with daily activities, sleep, mood, and quality of life 8, 9.

Abstract

Central neuropathic pain (central pain) may be a serious consequence of injuries or diseases affecting the central nervous system, occurring in up to 50% of patients following spinal cord injury, 25% with multiple sclerosis, and 10% following stroke. Central pain should be suspected if the pain: (1) arises at or within months following a lesion in the central nervous system with no other obvious cause, (2) is distributed within an area of sensory abnormality corresponding to the lesion, (3) is diffuse, (4) is described in terms such as burning, freezing, pins and needles, shooting, or squeezing, or (5) is unrelated to movements or specific positions of the pain-affected area. It is important to exclude nociceptive types of pain for which there may be a curative treatment. Randomized controlled trials support a pharmacological treatment similar to that used in peripheral neuropathic pain. Tricyclic antidepressants, pregabalin, and gabapentin are usually recommended as first-line treatment for central pain, while serotonin–noradrenaline reuptake inhibitors may be used if tricyclic antidepressants are contraindicated. Tramadol and opioids may be used as second-line treatment or escape medication. Central pain patients may be particularly prone to side effects, and an individual treatment approach is necessary.

Keywords

pharmacological treatment, spinal cord injury, central poststroke pain, multiple sclerosis