text: what would cause you to have dark red blood suddenly gush out of your nose without clotting?   most common causes of epistaxis (nosebleed) are: 1. trauma (accidental..or nose picking-seriously) 2. inflammation (infection, allergy, drug abuse-cocaine for example, dryness) 3. foreign body 4. coagulation disorder 5. and yes other things like hypertension, anti-coagulant usage, excessive alcohol intake.  you said that it didn't clot, but eventually stopped? either way, consult with your physician to make sure it's nothing more serious, soon.