Just to put this out there, because it was discussed in a recent first aid course I attended. This is coming from experienced emergency care specialists and paramedics, not me. Don't use regular tampons to treat nasal bleeding. Use purpose made nasal tampons. Unless you can apply direct pressure to the nasal tissue inside you head, regular tampons will only pool blood, cause clots to accumulate and risk asphyxiation or lodged clots to get infected way too close to the brain—or worse, lung infections from aspirated blood.

For what they are, menstrual tampons aren't actually that useful or absorbent. But absorbent is not something you want when treating wounds anyways. You want to stop the bleeding, not just to absorb the blood leaving the body, so what you actually need is to apply pressure on wounds. They also rip away the clotted tissue when removed, restarting the bleeding all over again.

Tampons are a quirky anecdote from those unprepared. But if you are taking the time to prepare then gauze, and cotton or muslin triangular bandages are far more versatile and useful for actual first aid.