Over the past four months, my right eyelid has become droopy; it opens more slowly than the left and is worse when I'm tired. A blood test for thyroid problems was negative. My doctor is not concerned, saying it may be a genetic fault that has only just become apparent. I am an otherwise healthy 21-year-old girl.
The fact that it is just one eyelid and no other muscle is involved does suggest that your doctor is correct. Your doctor has surely looked in detail at your eyes – at your pupils and how they react to light, if they are equal and regular in size, and whether both your eyes move in perfect coordination. Do you get double vision? Is it easier to look downwards than to look upwards? Do any of your other muscles get particularly tired or weak? There is a very small possibility that eyelid droop could be an early sign of a condition called myasthenia, and your doctor will certainly have considered this. If it is still bothering you, your doctor won't mind you going back for another chat, and to test your eyes again.

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