I would see your doctor about the drop in heart rate. I would recommend a test to check the coagulation of your blood. When was your last one?
The migraine may have been secondary in the drop in heart rate when the body constricts blood vessels to increase resistance and keep up the blood pressure. But, it could also be the cause of the drop heart rate because it will drop when people are in pain while the blood pressure increases. Dehydration is usually seen in a increase of HR and drop of blood pressure.
The diarrhea is normal once the heart rate goes back up. The GI tract is the last to get a blood supply during an event like this and once the supply gets replenished it will become overactive.
People with your condition (about 40%) will be anemic which can cause the symptoms you have mentioned. Another reason for a blood test. Its best to always keep your doctor informed of these types of issues for the best treatment.
Hope this helps!
Shyla RN
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