Chronic Pain Management After Herniorraphy

Inclusion Criteria: 1. History of unilateral inguinal herniotomy 2. Establishment of neuropathic character of chronic pain by means the LANSS painscore and DN4 score 3. Abnormal sensitivity (allodynia, dysesthesia, hypoesthesia or dysesthesia) in or around the incisional area 4. Duration pain ≥ 3 months 5. Medial or lateral inguinal hernia 6. Age ≥ 18 years 7. VAS score ≥ 40 mm on Vas scale on which they indicate 'how unpleasant or disturbing the worst pain was that they had today' 8. Grade III or IV pain and discomfort on the 4-point pain and discomfort scale 9. Informed consent (addendum V) Exclusion Criteria: 1. Participation in another trial 2. Age \< 18 years 3. Cognitive disfunction 4. Patient is unable to speak Dutch 5. Hereditary problems of galactose intolerance, Lapp lactase deficiency or glucosegalactose malabsorption 6. Patient classified as American Society of Anaesthesiologist Class 4 7. Renal impairment