NAPLEX (North American Pharmacist Licensure Examination) Practice Exam

What characterises biphasic/triphasic formulations (COC)?

1. Iron supplements included

2. 24 active + 4 placebo pills

3. Hormone levels change in phases

4. Only progestin included

The correct answer is: Hormone levels change in phases

Biphasic/triphasic formulations (COC) are characterized by changes in hormone levels in different phases of the menstrual cycle. This means that the level of hormones present in the pill will vary throughout the cycle, mimicking the natural hormonal fluctuations that occur in a woman's body. This is different from monophasic formulations, where the hormone levels remain constant throughout the menstrual cycle. Option A, iron supplements included, is not a defining characteristic of biphasic/triphasic formulations. While some formulations may include iron as a supplement, it is not a necessary component for a biphasic/triphasic pill. Option B, 24 active and 4 placebo pills, is a common dosing schedule for combination birth control pills. However, this does not necessarily mean that the pills are biphasic/triphasic. The important defining characteristic is the variation in hormone levels, not the number of active and placebo pills. Option D, only progestin included, is referring to a progestin-only pill (also known as the "mini pill"). This type of birth control does not contain any estrogen, making it different from combination pills like biphasic/triphasic formulations.