Plan B (levonorgestrel) tablets, 0.75 mg
Plan B is intended to prevent pregnancy after known or suspected contraceptive
failure or unprotected intercourse. Emergency contraceptive pills (like
all oral contraceptives) do not protect against infection with HIV (the
virus that causes AIDS) and other sexually transmitted diseases.
Each Plan B 100 mg tablet contains 0.75 mg of a single active steroid
ingredient, levonorgestrel [18,19-Dinorpregn-4-en-20-yn-3-one-13-ethyl-17-hydroxy-,
(17a)-(-)-], a totally synthetic progestogen. The inactive ingredients
present are colloidal silicon dioxide, potato starch, gelatin, magnesium
stearate, talc, corn starch, and lactose monohydrate. Levonorgestrel has
a molecular weight of 312.45, and the following molecular formula: C21H28O2.