Nickel allergy is a common cause of contact dermatitis, but not a well-known cause of gastrointestinal symptoms. Registered dietitian nutritionists, faced with a patient with multiple nontraditional food intolerances and continued gastrointestinal distress, worry about declining nutritional health. The prevalence of nickel allergy is estimated to be approximately 11.4% in the general population. Many clinicians are unaware that systemic nickel allergy syndrome causes symptoms similar to irritable bowel syndrome. Elimination of nickel in the diet is not possible, as it occurs naturally in the environment, but reducing exposure is possible. This case report describes a woman with dermatologic nickel allergy who experienced gastrointestinal symptoms and received a diagnosis of nonresponding irritable bowel syndrome. The patient noted that her multiple symptoms, both intestinal and extraintestinal, either resolved or were better managed after she started a low-nickel diet. This case demonstrates that clinicians should be aware of nickel allergy as a potential contributor to nonresponding irritable bowel syndrome.