Differential Diagnosis for Swollen Eyelid after Flying

• Single most likely diagnosis
  • Allergic reaction: This is a common issue that can occur due to various factors such as changes in air pressure, exposure to new allergens in the air, or an allergic reaction to something on the plane. Symptoms can range from mild to severe and include swelling, redness, and itching of the eyelid.
• Other Likely diagnoses
  • Dry eye syndrome: The dry air in airplanes can exacerbate dry eye syndrome, leading to irritation and swelling of the eyelids.
  • Contact dermatitis: Irritation from makeup, makeup removers, or other products used during the flight could cause contact dermatitis, leading to a swollen eyelid.
  • Sinus pressure: Changes in air pressure during the flight can cause sinus pressure, which may lead to swelling and discomfort around the eyes, including the eyelids.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Orbital cellulitis: Although rare, this is a serious infection of the tissues surrounding the eye that can cause swelling, redness, and pain. It requires prompt medical attention to prevent serious complications.
  • Angioedema: A severe allergic reaction that can cause rapid swelling of the face, lips, tongue, and throat, which can be life-threatening if not treated promptly.
• Rare diagnoses
  • Thyroid ophthalmopathy: A condition in which the tissues around the eye, including the eyelids, become inflamed due to Graves' disease. It's less likely to be directly related to flying but could be exacerbated by the stress of travel.
  • Chalazion or hordeolum (stye): A small bump on the eyelid that can become inflamed and swollen. While not directly related to flying, the dry air or stress of travel might exacerbate the condition.