Medically unknown symptoms include various symptoms and diagnoses that change as medical knowledge advances. These include illnesses such as fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, environmental sensitivities and chemical intolerances (or chemical sensitivities). It is unclear whether medically unknown symptoms are psychologic, physiologic, or both. These symptoms include fatigue, throat clearing and poor memory (see the accompanying table).

*—N = 381.

Reprinted with permission from Sabo B, Joffres MR, Williams T. How to deal with medically unknown symptoms. West J Med 2000;172:129.

Sabo and associates discuss how physicians deal with patients who present with medically unknown symptoms. Environmental sensitivities are probably a multisystem, multi-symptom disorder. Environmental and multiple chemical sensitivities are characterized by recurrent symptoms referable to multiple organ systems and occurring in response to exposure to many chemically-unrelated compounds at dosages far lower than those determined to cause harmful effects in the general population. The definitions of this clustering of medically unexplained symptoms have produced various labels that include multiple chemical sensitivities, environmental hypersensitivity syndrome, total allergy syndrome, environmental illness, idiopathic environmental intolerance, and environmental sensitivities.

Physicians who are clinical ecologists and practice environmental medicine believe that personal observation and experience are enough to allow diagnosis and facilitate treatment of patients with medically unknown symptoms. This approach differs from that of traditional medicine, which requires a clear diagnosis that corresponds to a particular disease. When patients have symptoms that fall outside current medical classifications, physicians tend to consider these symptoms psychologic in nature. This lack of validation by their physician can alienate patients and encourage them to seek alternative practitioners and opinions. The avoidance of inciting triggers is often recommended, but this can lead to isolation, poor coping skills and further disability. In addition, after undergoing a variety of tests, patients may be told that they are sensitive to a wide range of triggers, making avoidance difficult. This may result in everything becoming a trigger of symptoms. The traditional appointment visit may not be adequate for patients with symptoms that defy the usual diagnostic criteria. Therefore, physicians must provide more time for these patients to enhance communication and foster information exchange.

The authors conclude that four simple solutions can improve the health outcomes of persons with environmental sensitivities. The most important step is for physicians to listen respectfully to the patient without prematurely labeling the symptoms as psychologic. Second, physicians should acknowledge the experience for the patient, encouraging a mutual effort toward resolving the symptoms. Third, physicians can reassure the patient that although symptoms may remain, functioning will improve with appropriate management. Fourth, physicians should conduct a complete assessment that includes an occupational and environmental history to identify possible triggers. Following these steps may help patients avoid developing a long-term, disabling illness.