purple lips

My cardio told me I have a healthy heart, although I do have mild mvp, mild mr and tr, IST and NCS (and being evaluated for another possible cause of syncope). I am taking Toprol XL 50 mg and salt tabs, and I take supplements. I exercise reg., too.
My family has told me a few times about my lips being purple. My lips seem to be pale most of the time to begin with, but occasionally they get white and (mostly) purple. My brother who is an EMT said it isn't normal and I should tell my dr.(but my bro. hasn't actually seen my lips like that).  Do you know of anything that might cause this? Thanks.

[CCF-M.D.-CRC]

Dear jan,
Low oxygen content of the blood can cause blue lips.  This can be due to low blood counts or due to problems with oxygenation of the blood.  It would be interesting to know what your blood oxygen saturation is during the episodes.  Do they last for very long?  If so then your brother may have time to come over to your house to check with a saturation monitor (many EMTs have this equipment).   If it is low then your doctor would have to look for sources of low blood oxygen such as blood clots, sickle cell disease or other hemoglobin abnormalities.  A hematologist could check for these various disorders.

[minnie10]

A related discussion, bruising on lips was started.

[mari20]

A related discussion, What's causing Purple lips and Shortness of breath was started.