What Is 'Moon Face'? Amy Schumer's Appearance Has Worried Fans Speculating

Over the last 24 hours, curious fans have been googling a medical term known as "moon face" after actor and comedian Amy Schumer appeared as a featured guest on Jimmy Fallon's "The Tonight Show." Popular search terms have included "Is Amy Schumer sick," which increased by 5,000% over the last day, as well as "moon face" searches being up by 750%. The interest came after some viewers took to social media stating how they felt the star's face looked particularly round in shape during her interview. We're not here to discuss anyone's physical appearance, as body image is a very personal subject. Rather, due to recent increased interest, we're here instead to answer questions about what causes moon face and whether or not it is cause for concern.

While not a formal medical diagnosis, moon face is the result of facial swelling due to a buildup of excess fat or fluid in the face, explains Medical News Today. This swelling can cause the face to take on a round, more circular shape like that of a full moon. Hormonal fluctuations, steroid usage, or certain medical conditions can all cause this buildup to occur. Moon face on its own does not pose any health risks.

While health conditions such as hypothyroidism and Cushing's syndrome — a condition characterized by an overproduction of cortisol in the body — can prompt cases of moon face, fans were primarily speculating as to whether Schumer's appearance may potentially be related to prednisone use. As a result, Google searches for "Prednisone Face Swelling" have been up by 300% since yesterday.

Prednisone, a prescription corticosteroid medication, can be used to treat a variety of inflammatory conditions, including allergies, arthritis, skin conditions, psoriasis, and more (via Drugs.com). A number of side effects have been noted in association with the drug, such as insomnia, mood changes, stomach pain, headache, bloating, and acne. Prednisone has also been shown to potentially increase one's appetite, prompt gradual weight gain, or induce changes in the shape or distribution of body fat. Areas that may be affected include both the face and neck, among other regions.

If the occurrence of moon face is related to a specific health condition, treating the underlying condition can help reduce facial swelling. For cases of moon face related to steroid use, talking to one's doctor about using an alternate steroid medication or adjusting the dosage may prove helpful.