Numbness and allodynia usually indicate nerve damage. Intercostal nerve damage during thoracic resection may produce post-thoracotomy pain syndrome. Gabapentin is an anticonvulsant medication commonly used for neuropathic pain. Because the patient is already using an opioid and a nonopioid, adding an adjuvant is the missing step of the WHO ladder. Nonsteroidal anti-inflammatory drugs are not usually effective for neuropathic pain.