Codeine Products Used By Nursing Mothers
Audience: Obstetricians, pediatricians, other healthcare professionals, consumers
[Posted 08/17/2007] FDA issued a Public Health Advisory with important new information about a very rare, but serious, side effect in nursing infants whose mothers are taking codeine and are ultra-rapid metabolizers of codeine. When codeine enters the body and is metabolized, it changes to morphine, which relieves pain. Many factors affect codeine metabolism, including a person’s genetic make-up. Some people have a variation in a liver enzyme and may change codeine to morphine more rapidly and completely than other people. Nursing mothers taking codeine may also have higher morphine levels in their breast milk. These higher levels of morphine in breast milk may lead to life-threatening or fatal side effects in nursing babies. In most cases, it is unknown if someone is an ultra-rapid codeine metabolizer.
When prescribing codeine-containing drugs to nursing mothers, physicians should choose the lowest effective dose for the shortest period of time and should closely monitor mother-infant pairs. There is an FDA cleared test for determining a patient’s CYP2D6 genotype. The test is not routinely used in clinical practice but is available through a number of different laboratories. The results of this test predict that a person can convert codeine to morphine at a faster rate than average, resulting in higher morphine levels in the blood. When levels of morphine are too high, patients have an increased risk of adverse events.
FDA公布了一则公共卫生通知：有关授乳母亲是超快速可待因(codeine)代谢者，服用可待因后对婴幼儿造成少见但非常严重之不良反应。可待因进入人体代谢转变成吗啡(morphine)缓解疼痛。很多因素影响可待因之代谢，包括人体本身之基因构成。部分人在肝酵素代谢上有变异性，相较于一般人可快速完整地由可待因代谢成吗啡。授乳母亲服用可待因，也可能有较高之吗啡浓度分泌在乳汁中，会危及到哺乳之婴幼儿。大多情况，并不知道是否为超快速可待因代谢者。
当医师为授乳之母亲开立含可待因之药品时，应该选择短期最低之有效剂量，并应该密切监测母亲及幼儿。 FDA cleared test监测病患CYP2D6基因型态，临床上该项监测非常规性，但在不同实验室所使用。实验结果可预测：可快速将可待因转变为吗啡的人导致较高之吗啡血中浓度，当吗啡血中浓度过高，病患会有较高之不良反应发生。
详细内容参照网址:
http://www.fda.gov/medwatch/safety/2007/safety07.htm#Codeine |
发表于 2007-9-18 19:02:00