Patients using antibiotics, steroids, NSAID, aspirin, probenecid or antihistamines for an extended regimen of at least 10 or more consecutive days, or any immunosuppressants, anticoagulants, dilantin, lithium, methotrexate, phenothiazines, investigational drugs with pharmacological activity that could compromise the test product safety during the 30 days immediately preceding the first treatment visit.