The use of capsaicin as a potential analgesic drug for postoperative pain relies on the ability of capsaicin to induce membrane lysis of c-nerve fibers. In a previous randomized placebo controled blinded study of this effect we found a significant effect of capsaicin versus placebo. Before surgery all patients were examined by quantitative sensory testing to evaluate sensory function. In this study an identical sensory testing will examine if changes to the sensory function in capsaicin treated patients is identical to placebo treated patients.No new intervention will be performed

Inclusion Criteria:

• Primary groin hernia planned to undergo Lichtenstein mesh repair
• Ability to use pain scales
• American Society of Anesthesiologist class I or II based upon medical history, physical examination, and screening laboratory results
• Willing to take oral pain medication (acetaminophen, ibuprofen) for the first week
• Willing to fill out a diary for four weeks following surgery.

Exclusion Criteria:

• A previous lower abdominal surgical procedure
• Bupivacaine, acetaminophen, ibuprofen, or tramadol
• A medical condition likely to alter wound healing or pain ratings
• Systolic blood pressure greater than 150 or diastolic greater than 95 mm Hg
• Contraindication to general anesthesia
• Bilateral hernia repair
• A history of drug or alcohol abuse within the past two years
• Use of antihypertensive, antidepressant, or psychotropic drug that has not been stable for 3 months
• Use of an investigational drug within 3 months or scheduled to receive an investigational drug other than ALGRX 4975 during the study period.

Adult males with primary unilateral groin hernia