E-DRUG: Norgestrel and combined contraceptive pills (cont'd)

[John Urquhart <urquhart@netcom.com>]

E-drug: Norgestrel and combined contraceptive pills (cont'd)
---------------------------------------------

The reason has to do with the fact that a 5-year supply of
levonorgestrel takes up half as much space as a 5-year supply of the
racemic mixture. As it is, NORPLANT is rather bulky for a
trochar-inserted implant, requiring 6 separate tubes about the
dimension of a long-grain rice grain. (the dimensions are in the
product labeling, or you can consult the review I wrote in the
November issue of Brit J Clin Pharmacol, reference to which I gave in
an earlier exchange on this topic) I was not involved in its
development, but have been in other such projects when I was Chief
Scientist at ALZA in the period 1974-85. The decision to use a
configuration that could permit insertion by trochar was probably the
right one, given the dexterity of most gynecologists, rather than
placing a system in a subcutaneous pocket created by an incision.

The latter maneuver would permit a much larger system to be placed
that could have accommodated the racemic mixture, and of course,
would probably ave been a lot more easily removed than the
rice-grains, which turned out in the marketplace to be a major problem
when patients wanted to discontinue their use of the product.

The short-lived popularity of NORPLANT, ended by stories of difficult
removals and groundless, irrational fears of toxicity from SILASTIC,
suggests that another design with other membrane materials might be
the basis for a widely-used product. There is a large unmet need for a
mode of contraception that does not require the discipline of punctual,
once-daily dosing. The IUDs were once the answer, but they fell from
grace; then NORPLANT came, and it fell from grace. Presently, there is
not a satisfactory long-lasting, reversible contraceptive modality.

John Urquhart
urquhart@netcom.com
--
Send mail for the `E-Drug' conference to `e-drug@usa.healthnet.org'.
Mail administrative requests to `majordomo@usa.healthnet.org'.
For additional assistance, send mail to:  `owner-e-drug@usa.healthnet.org'.