We encountered a case of hypercobalaminemia induced by oral intake of an energy drink after total gastrectomy. The patient was referred to our hospital due to findings suspicious for gastric cancer on screening. A 20 mm type 0-IIc lesion was detected in the gastric subcardia on esophagogastroduodenoscopy. Total gastrectomy followed by Roux-en-Y reconstruction was performed. He was discharged without complications. His basal serum vitamin B₁₂ level was initially maintained with monthly intramuscular injections of vitamin B₁₂. After 9 months, his serum vitamin B₁₂ level suddenly increased up to 36-fold higher than the normal range and persisted there for one year without vitamin B₁₂ injections. The patient ultimately reported consuming half a bottle of an energy drink each day during this time period. This case demonstrates the risk of unexpected hypervitaminemia resulting from self-administration of nutritional supplements.

　　Epidermal growth factor receptor (EGFR) gene mutation examination is now performed in most medical institutions in order to select the molecular targeted medicine for lung cancer. It became clear that the positive rate of the biopsy material was lower than that of the surgical sample in this hospital. The cause was attributed to false negatives due to low tumor cell content in biopsy specimens. We investigated the presence of the mutation using surgical samples and preoperative biopsy specimens from the same patients in 13 cases. Furthermore, we investigated the tumor cell content of the biopsy specimens by cell counting. Results showed that 3 of 6 biopsy specimens that were associated with positive surgical samples were judged to be negative. The tumor cell content was less than 5% in all negative cases. Regarding EGFR gene mutation examination, we should carefully determine tumor cell content when using biopsy specimens.

Objective: Many of the elderly patients are suffering from constipation, are using the oral laxative.  However the risk assessment of the oral laxative is not performed.  Therefore, we used Japanese Adverse Drug Event Report database (JADER) and examined for the safety of the oral laxative in the elderly patients.
Methods: Since the analysis target medicines; 12 oral laxatives and target ADEs; “digestive disorders” and “electrolyte abnormality,” the JADER database for April 2004 to January 2015 were analyzed in adults of age exceeds 60.  We used the reporting odds ratio for a safety index of drugs, using reporting odds ratio, when the Lower bound of the 95% two-sided confidence interval exceeds 1, it is the signal detection of ADE.
Results: The oral laxatives detected the signal of “digestive disorders” were three medicines, and “electrolyte abnormality” were five medicines.  Especially, for electrolyte abnormalities not only increases the blood magnesium values as magnesium oxide, that there is also affect other electrolyte revealed.
Conclusion: Some oral laxatives were also intended to signal detections of the adverse events that are not listed in the attached document, it is necessary to pay attention to the use of them for the elderly patients.

Objective: Elderly patients commonly experience adverse drug events (ADEs) owing to their poor drug metabolizing and excretion ability, and these often cause multiple organ dysfunction syndrome.  Therefore, it is important that we identify the adverse drug events early on during prognosis.  We searched for oral medicines that might exacerbate the prognosis of ADEs in elderly patients.
Methods: The objects under analysis were oral medicines that were registered in the Japanese Adverse Drug Event Report database (JADER).  The associations between the elderly/non-elderly patients and exacerbation risk/non-exacerbation risk were analyzed by risk ratios (RR).  The signal detection of exacerbation risk was defined as 95% confidence interval of lower limit of risk ratio>1 and χ²≥4.
Results: The oral medicines that might markedly exacerbate the prognosis of ADEs in the elderly patients in comparison with the ADEs of young patients included 84 items, of which 63 have not been described as potentially inappropriate medicines in all guidelines for medical treatment of the elderly patients.
Conclusion: In this study, while we could not search for oral medicines having a high risk of ADEs, we were able to search for oral medicines that might exacerbate the prognosis of ADEs in elderly patients.  This result could contribute to the proper use of medicines in the elderly patients.