過 度 活 躍 症

=^.^=mommy

朋友的囝囝患有過度活躍症, his son take ( Ritalin ) for few years. Last week, he saw a newspaper; it said that if過度活躍症的兒童 take (Ritalin) for long-term treatment, 兒 童患 有 cancer的 風 險 較正 的 高1倍. Does anyone know that?  :-|  :-|

Dr.T

似乎都不算新聞(1996!)...是在某種老鼠的身上某較易患癌的部分發現,但美國藥物管理局(FDA)認為人類在正常劑量下使用是安全的,詳見下文:

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Jan. 12, 1996 RITALIN STUDIES

FDA has taken steps to alert the health care community thatan animal study of Ritalin, a stimulant widely prescribed for children with attention deficit hyperactivity disorder (ADHD), has produced a "weak signal" that the drug may have the potential to cause cancer.

The agency continues to regard Ritalin as a safe and
effective drug.  However, the signal indicates a potential risk that needs to be considered and further studied because of the increasing and often long-term use of Ritalin in children. In the
last five years, the use of the product has increased
approximately two-to-threefold.

The agency's actions are based on findings in a draft report on two two-year studies by the National Toxicology Program (NTP) on cancer-causing potential of Ritalin in mice and rats.

The study in rats revealed no cancer-causing activity.  The findings in mice included increased rates of a non-cancerous liver tumor (hepatocellular adenomas) and, in males only, the occurrence of malignant liver tumor (hepatoblastomas).

FDA considers the results of the studies a signal of a weak cancer-causing potential for this drug, based on the following:
-- The positive findings were seen in one species of rodent (the mouse) and in only one organ -- the liver -- which is known to be particularly likely to develop tumors to a wide variety of stimuli.
-- The increased rates were seen primarily in non-malignant tumors.
-- There was no increase in mortality associated with the tumors.

The agency also noted that animal studies do not necessarily reflect human findings. The kind of liver tumor found in mice is extremely rare in people, and its occurrence in recent years has not increased despite the increased use of Ritalin.

The agency has asked the drug's sponsor to include the positive findings in the labeling for Ritalin, and to alert prescribers to the "weak signal" by sending them a Dear Doctor letter. FDA also plans to initiate additional followup studies, including both animal tests and epidemiological studies in humans
using Ritalin.

Ritalin is manufactured by Ciba Pharmaceuticals, division of Ciba-Geigy Corp. in Summit, N.J.