In her TEDx talk “Sex Matters in Emergency Medicine,” Dr. Alyson McGregor shares an astounding fact: of all drugs withdrawn from the market, 80% are withdrawn because of their side effects on women. This number cannot be attributed to simple chance or coincidence. As Dr. McGregor explains, this number stems from a long history of excluding women from medical research. If we primarily test our drugs on male cell lines, male lab animals, and male subjects in human clinical trials, we cannot expect our drugs to work as well on women.

According to a recent article in American Journal of Physiology – Cell Physiology, many researchers choose to use only male animals in their studies out of convenience. Female animals experience fluctuating hormone levels during their reproductive cycles; researchers fear that this will lead to fluctuations and anomalies in their data. It is assumed that male-only data will still be applicable to females because men and women are the same except for their reproductive systems. This, however, is a misconception. In reality, every cell in our bodies carries our sex chromosomes, which have the capacity to influence our most fundamental cell functions. As a result, men and women may react differently to certain drugs.

Female physiology and female drug responses are unique.

Image Source: SEBASTIEN BOZON

In addition to being different on the cellular level, women typically weigh less than men. Yet, according to a publication by Dr. Gail D. Anderson, most drug dosage recommendations are not based on body weight. This means that women are often being overprescribed medications. Even after adjusting for weight, women have a higher body fat percentage than men, leading to a wider drug distribution in the body and consequently, longer-lasting effects. Women also metabolize drugs at different rates than men. For example, the FDA recommended new, lower doses for Ambien, a sleep medication, partially due to the fact that it is metabolized more slowly by women.

Too-high doses of Ambien put women at risk for falling asleep while driving.

Image Source: Bloomberg

However, it is not just biological sex that can affect one’s interactions with medicine. An infographic released by the National Institutes of Health illustrates the capacity of gender – defined as “the socially constructed roles, behaviors, expressions, and identities of girls, women, boys, men, and gender diverse people” – to also influence our health and medical treatment. For example, women often take the responsibility of caring for their families, leading them to neglect seeking care for their own health.

Medicine continues to advance with new research and new technologies. But as we progress, we must account for sex and gender differences in drug response and health risk. Otherwise, we continue to ignore and endanger half the world’s population.

Feature Image Source: Esparta Palma

Niathi Kona

Author Niathi Kona

Niathi Kona is a fourth-year Public Health major at UC Berkeley. She is interested in studying how the healthcare system can more effectively serve patients of varied cultures, socioeconomic backgrounds, and gender identities. She is also fascinated by vision science and loves to sing, eat, read, write, and teach. (updated Mar 2019)

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