著者

吉村 勇哉 藤﨑 孝輔 山本 武範 篠原 康雄

出版者

公益社団法人 日本薬学会

雑誌

YAKUGAKU ZASSHI (ISSN:00316903)

巻号頁・発行日

vol.137, no.5, pp.581-587, 2017-05-01 (Released:2017-05-01)

参考文献数

16

被引用文献数

3 7

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Magnesium oxide (MgO) tablets are widely used as laxatives in patients with constipation. Recently, the “Revision of Precautions on the Use of Magnesium Oxide” has been issued by the Japanese Pharmaceuticals and Medical Devices Agency, warning against the risk of hypermagnesemia with the use of MgO. However, the majority of physicians continue to administer MgO for constipation without adequately considering its safe use. In the present study, we performed two analyses using an identical lot of MgO tablets and evaluated the risk of hypermagnesemia. Approximately 90% of the MgO tablets dissolved within 120 min in dissolution testing; it was believed to form an absorbable state for magnesium. With orally administered MgO, 15% is absorbed in the body and 85% is excreted via the feces without being detected in pharmacokinetic analysis. Magnesium absorbed into the plasma demonstrated peak concentration 3 h after administration and was excreted via the urine within 48 h.

著者

富田 隆 後藤 英和 吉村 勇哉 坪内 良子 中西 利恵 小島 千賀子 米島 美穂子 吉田 正 田中 勝也 住谷 賢治 幸田 幸直

出版者

公益社団法人 日本薬学会

雑誌

YAKUGAKU ZASSHI (ISSN:00316903)

巻号頁・発行日

vol.135, no.6, pp.835-840, 2015-06-01 (Released:2015-06-01)

参考文献数

8

被引用文献数

11 17

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It has been reported that magnesium oxide tablets are excreted in a non-disintegrated state in the stool of patients when the tablets are administered after being immersed in a food thickener. Therefore we examined whether immersion in a food thickener affects the pharmacological effect in patients taking magnesium oxide tablets, and whether immersion affects its disintegration and solubility. The mean dosage (1705 mg/d) was higher for patients who took tablets after immersion in a food thickener than for those who took non-immersed tablets (1380 mg/d). The disintegration time and dissolution rate of the immersed tablets were lower than those of non-immersed tablets in vitro. Furthermore, components that constitute the food thickener and differences in composition concentrations differentially affect the disintegration and solubility of magnesium oxide tablets. This suggests that commercially available food thickeners are likely to be associated with changes in the degradation of magnesium oxide tablets, and they therefore should be carefully used in certain clinical situations.