In case of a nose bleed that persisted for more than 15 minutes you should?

If a nosebleed persists for more than 15 minutes, you should seek medical attention immediately. While waiting for help, sit upright and lean slightly forward to prevent blood from flowing down the throat. Pinch the nostrils together and apply pressure while breathing through your mouth. Avoid lying down or tilting your head back, as this can lead to swallowing blood.