Are antidepressants effective for neuropathic pain?
The NNH* for major adverse effects, defined as an event leading to withdrawal from a study, was 28 for amitriptyline and 16.2 for venlafaxine. The NNH for minor adverse effects such as drowsiness, dizziness, dry mouth and constipation was 6 for amitriptyline and 9.6 for venlafaxine. *NNH = number needed to treat to cause harm in one individual.
Neuropathic pain can be very disabling, severe and intractable, causing distress and suffering for individuals, including dysaesthesia and paraesthesia. For many years antidepressants have been used to manage neuropathic pain, and are often the treatment of first choice. It is not clear, however, which antidepressant is most effective, what role the newer antidepressants, such as SSRIs and venlafaxine, can play in treating neuropathic pain and what adverse effects are experienced by patients.