My seven year old has always been prone to nosebleeds. It got to the point that he would have a nose bleed every day.
I started giving him 1 alfalfa tablet each day, just the Now brand.
I have been doing this for 3-4 weeks. He has missed a dose here and there but he has not had a nose bleed in at least a couple of weeks.
I suspect the vitamin K in the alfalfa is what helps the most, though alfalfa is very nutritious over all.
In fact, when we had goats, we would seek out and buy alfalfa hay for our goats because it provided better nutrition for them than most hays.
~Mama to Many~