Intrauterine Drug Delivery Systems

Intravaginal drug delivery systems bypass first-pass metabolism, enhancing bioavailability and often making them more efficient than oral administration.

These systems include matrix diffusion-controlled devices, like medroxyprogesterone acetate in silicone, and dissolution-controlled devices, using progestin and estrogen dispersion in PEG and silicone.

Such devices are often formulated as vaginal rings, which provide sustained hormone release for up to 21 days, offering a cyclic intravaginal contraception.

For long-term contraception, intrauterine devices or IUDs are commonly used as they remain effective for 12 months to several years, depending on the device type.

Copper IUDs, commonly T- or 7-shaped, gradually release copper ions that exert a localized contraceptive effect lasting over three years.

The progesterone-releasing IUD is also a T-shaped device that releases progesterone dispersed in a silicone polymer through a controlled membrane.

As a result, it provides a consistent hormone dose, offering effective contraception for up to one year.