Hello - I've never had this while swimming, but I've had a few episodes over the last few years of having terrible burning/tearing. They've been infrequent enough that I haven't had it checked out, but if this continues to bother you, I would certainly mention this to your doctor.
Also, keep in mind that drops that are designed to “get the red out” and those that contain preservatives are generally more *irritating* than helpful for those of us with eye issues due to Graves'.
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