藥物警訊

Gadolinium-based Contrast Agents for Magnetic Resonance Imaging (MRI): Drug Safety Communication - FDA Evaluating the Risk of Brain Deposits With Repeated Use

AUDIENCE: Radiology

ISSUE: FDA is investigating the risk of brain deposits following repeated use of gadolinium-based contrast agents (GBCAs) for magnetic resonance imaging (MRI). Recent publications in the medical literature have reported that deposits of GBCAs remain in the brains of some patients who undergo four or more contrast MRI scans, long after the last administration. It is unknown whether these gadolinium deposits are harmful or can lead to adverse health effects.

FDA, including its National Center for Toxicological Research (NCTR), will study this possible safety risk further. FDA is working with the research community and industry to understand the mechanism of gadolinium retention and to determine if there are any potential adverse health effects. Based on the need for additional information, at this time, FDA is not requiring manufacturers to make changes to the labels of GBCA products.

BACKGROUND: After being administered, GBCAs are mostly eliminated from the body through the kidneys. However, trace amounts of gadolinium may stay in the body long-term. Recent studies conducted in people and animals have confirmed that gadolinium can remain in the brain, even in individuals with normal kidney function. Available information does not identify any adverse health effects.

RECOMMENDATION: To reduce the potential for gadolinium accumulation, health care professionals should consider limiting GBCA use to clinical circumstances in which the additional information provided by the contrast is necessary. Health care professionals are also urged to reassess the necessity of repetitive GBCA MRIs in established treatment protocols.

Patients, parents, and caregivers should talk to their health care professionals if they have any questions about the use of GBCAs with MRIs. This issue affects only GBCAs; it does not apply to other types of scanning agents used for other imaging procedures, such as those that are iodine-based or radioisotopes.

Read the MedWatch safety alert, including a link to the FDA Drug Safety Communication, at:
http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHuma...

美國FDA發布藥物安全警訊，依據近期發表的醫學文獻，部分曾接受4次以上磁振造影(magnetic resonance imaging, MRI)的病人，於最後一次給藥後再間隔一段時間去測，發現仍有含gadolinium類成分顯影劑(gadolinium-based contrast agents, GBCAs)蓄積於腦部之情形。美國FDA將對於此風險進行評估，目前尚無法確認gadolinium蓄積是否會造成傷害或任何潛在性副作用。

GBCAs給藥後大部分由腎臟排除，但少量會長期存在體內。近期研究證實即使腎功能正常，使用gadolinium後仍有部分會殘留於腦部。

為了減少gadolimnium蓄積之潛在危險，美國FDA建議醫療人員應在此藥品可提供臨床上額外資訊時，才考慮使用，也建議應重新評估目前治療準則中重複使用GBCAs進行磁振造影之必要性。

病人、家屬及照顧者如有任何問題，應向醫療人員諮詢，此風險目前僅於GBCAs發現，其他類型顯影劑，如含碘類顯影劑或放射性顯影劑並不適用。

相關訊息與連結請參考FDA網址：

http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHuma...

資料來源：美國FDA之藥物安全警訊
資料提供：台大醫院藥劑部