Anorexia in cancer patients has a variety of causes and impairs patients’ quality of life. However, there have been few reports of thiamine deficiency (TD) playing a role in anorexia during palliative care. The objective of this report was to describe such a case.

An 82-year-old woman with advanced cervical cancer was admitted for palliative care because of progressive disease. One month after admission, she developed myoclonus on the left side, difficulty speaking, slurred speech, and drooping of the left corner of the mouth, with no consciousness disturbance. She also developed nausea and complained of decreased dietary intake for more than 2 weeks.

The patient’s thiamine level, which had been measured 2 weeks earlier, was 27 ng/ml, which was below the normal range, and 100 mg of thiamine was administered intravenously. After 2 hours, the patient’s neurological findings resolved, and her dietary intake improved from 30% to 40% of meals to 90% to 100%. Subsequently, the patient did not experience similar symptoms, and her clinical course was stable. Based on the patient’s clinical course, gastrointestinal beriberi was diagnosed.

This case shows that TD may cause anorexia. Many patients who receive palliative care have decreased dietary intake. Consequently, such patients may present with gastrointestinal beriberi, as in the present case. Appropriate diagnosis and treatment may contribute to increasing such patients’ quality of life. It may be necessary to differentiate TD from other conditions as a cause of anorexia in patients receiving palliative care.