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Abstract
The disappearance of levonorgestrel from plasma after the removal of NORPLANTR subdermal implants was studied in 12 women who had been treated from 5.5 to 78 months.
The existence of one or two half-lives for the rate of disappearance was assessed.
The influence of body weight, body fat and length of treatment upon levonorgestrel
clearance was studied through stepwise regression analysis.
It was found that the levonorgestrel decay rate after implant removal can be entirely
accounted assuming one half-life of ![Math Eq]()
. Stepwise regression analysis showed that levonorgestrel half-life is positively
correlated with body weight and not significantly correlated with the length of treatment
or body fat. It is concluded that, after long-term administration of levonorgestrel
via subdermal implants, the major part of the steroid is cleared from plasma within
96 h and that only trace amounts are detected in the following days.
. Stepwise regression analysis showed that levonorgestrel half-life is positively
correlated with body weight and not significantly correlated with the length of treatment
or body fat. It is concluded that, after long-term administration of levonorgestrel
via subdermal implants, the major part of the steroid is cleared from plasma within
96 h and that only trace amounts are detected in the following days.To read this article in full you will need to make a payment
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References
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Article info
Publication history
Accepted:
August 2,
1988
Received:
July 6,
1988
Identification
Copyright
© 1988 Published by Elsevier Inc.
