Q: I woke up yesterday morning, after a normal night’s sleep, with a bright red spot on the inner portion of the white of my left eye. It isn’t at all painful and I wouldn’t have even known it was there, but my wife noticed it and asked me if I had somehow injured it. I hadn’t. My vision seems fine, the red spot is still about the same size, and there’s still no pain. Should I be concerned?

A: Your description matches that of a subconjunctival hemorrhage. The conjunctiva is a very thin clear membrane that covers the entire front of the eye and the inner portions of the eyelids. Your problem was caused by a small amount of bleeding from a very tiny blood vessel just beneath this membrane.

This can occur following a very hard sneeze or an episode of very harsh coughing, both of which cause a momentary spike in the pressure within all of the blood vessels in the head.

Such events probably cause other tiny blood vessels in the head and neck to “leak” like this, but such bleeding is generally only visible in the eye, due to the clear covering of the conjunctiva.

If you look very closely at the eye, you should notice that the red spot comes right up to the edge of the iris (the colored portion of the front of the eye) but does not spread into the area through which light passes to get into and to the back of your eye, hence no effect on your vision. And, like a bruise anywhere else on your body, this virtually always clears completely over a week or so with no treatment at all.

To learn more about this and many other health topics, visit the American Academy of Family Physicians’ website, familydoctor. org, where you can search for your topic of interest.

I want to thank John P. for asking this question. If you have any particular topic you would like to hear more about, message me at paulmdake@gmail.com.

Dr. Paul Dake, a Newberry native, is a retired family physician. He lives in Pinconning, Michigan.