Fenobam on Heat/Capsaicin Induced Hyperalgesia in Healthy Volunteers

All subjects will receive a topical dose of capsaicin cream 0.1%(Capzasin-HP) to the forearm at the start of the study visit. The order of the 2 treatment regimens indicated below will be randomized and blinded to subjects and researchers.

Treatment Regimen 1: Fenobam [1-(3-chlorophenyl)-3-(1-methyl-4-oxo-2-imidazolidinylidine) urea hydrate]: administration of one 150 mg gelatin capsule.

Treatment Regimen 2: Placebo (lactose monohydrate): administration of one 150 mg gelatin capsule.

Inclusion criteria

• 18-50 year old
• Good general health with no remarkable medical conditions (e.g. liver, kidney, heart, or lung failure)
• BMI between 20-33
• Willing to comply with study guidelines as outlined in protocol [including: women of childbearing age must be willing to use a double-barrier method (e.g. oral contraception and condom) for contraception during participation in the study]
• Willing to provide informed consent

Exclusion criteria

• Anatomical malformation of upper extremities
• Status post recent trauma or chronic lesions on either forearm
• Medication use (includes vitamin, herbal, dietary and mineral supplements and grapefruit products during or within 14 days prior to study participation; excludes contraceptives)
• History of allergy or intolerance to capsaicin
• History of multiple drug allergies
• History of addiction to drugs or alcohol (prior or present addiction or treatment for addiction)
• History of chronic pain syndromes
• Pregnant and nursing females
• Smokers