King Charles' Alarming Bloodshot Eye, Explained

King Charles has faced several medical issues in recent years, but one was hard to miss during French President Emmanuel Macron's recent visit to Windsor Castle. His right eye appeared noticeably red.

While the King's bloodshot eye sparked concern about another possible health issue, palace representatives said he had burst a blood vessel in his eye — a condition known as a subconjunctival hemorrhage (per People). The 76-year-old is currently being treated for cancer, and NBC News reported that he was hospitalized in March due to side effects from the treatment. However, the broken blood vessel is unrelated to his cancer care.

(Here's when you should see an eye doctor.)

A subconjunctival hemorrhage is similar to a bruise, but it occurs on the surface of the eye. While the redness may look alarming, it typically doesn't cause pain or vision problems. Many people don't realize they have one until they notice the bright-red patch in the normally white part of the eye.

A subconjunctival hemorrhage can occur from straining, such as a forceful cough, an intense sneeze, vomiting, or constipation. You can also break a blood vessel in your eye from trauma, like rubbing your eye too hard or getting hit in the eye.

Age may increase your risk, especially if you have diabetes or high blood pressure (here's how high blood pressure affects your eyes). People who wear contact lenses or have recently had eye surgery may also experience this condition. According to a 2013 article in Clinical Ophthalmology, certain infections, rare blood disorders, and even menstruation may trigger a subconjunctival hemorrhage. Blood thinners can also be a cause.

Eye drops won't treat a subconjunctival hemorrhage, but they can help relieve irritation. Most of these red spots clear up within one to two weeks, depending on the size. However, if you experience them frequently or have eye pain, it's a good idea to see an eye specialist. In some cases, a subconjunctival hemorrhage may signal an underlying condition such as a vascular disease, bleeding disorder, or even asthma.