Seeing streaks of blood or bloody mucus after blowing your nose while sick can be unsettling. However, a small amount of blood mixed with nasal discharge is common during respiratory illnesses like a cold or sinus infection. The appearance of blood usually signals a minor disruption to the delicate nasal lining, often due to inflammation and the effort of clearing congestion. This temporary symptom is rarely a cause for alarm.
Why Illness Causes Blood When Blowing Your Nose
The primary reason for seeing blood during an illness is the heightened vulnerability of the nasal lining, or nasal mucosa. When a virus or bacteria causes a cold or sinusitis, the immune response triggers inflammation within the nasal passages. This inflammation causes the tissue to swell, bringing the tiny blood vessels, or capillaries, closer to the surface.
The capillaries most often involved are concentrated in a specific area on the nasal septum called Kiesselbach’s plexus. This dense network is already fragile, and swelling from infection makes the vessels more susceptible to injury. Illness often leads to dryness within the nasal cavity, exacerbated by low humidity or frequent breathing due to congestion. This dry environment causes the swollen mucosa to crack, making the underlying capillaries easier to rupture.
Blowing the nose introduces a third factor: pressure trauma. When a person forcefully clears their nose, the sudden, high-pressure air acts as a mechanical stressor on the weakened capillaries. This trauma easily ruptures the superficial vessels in Kiesselbach’s plexus, resulting in bright red blood or blood-tinged mucus. The streaks of blood are evidence of a minor capillary break from the combined effects of inflammation, dryness, and pressure.
Immediate Steps for Safe Nose Blowing and Relief
Managing this symptom starts with adopting a gentler technique for clearing the nasal passages to minimize pressure on fragile capillaries. Instead of blowing forcefully through both nostrils, press a finger gently against one side of the nose to close the nostril. Then, gently blow air out through the open nostril into a tissue. This technique allows for effective clearance while preventing the rapid pressure spike that can cause small vessels to burst.
Maintaining moisture in the nasal environment is an important preventative measure to keep the nasal mucosa supple. Saline nasal sprays or gels can be used two to three times a day to hydrate the passages and prevent cracking. Using a cool-mist humidifier, particularly overnight, introduces moisture into the air and counteracts the drying effects of central heating.
If a minor nosebleed occurs, remain calm and sit upright, leaning slightly forward to prevent blood from dripping down the throat. Swallowing blood can irritate the stomach and induce vomiting, which may restart the bleeding. Pinch the soft part of the nose, just above the nostrils, using your thumb and index finger. Apply firm, continuous pressure for 10 to 15 minutes, breathing through your mouth, without releasing the pressure to check the bleeding.
Actions that cause further trauma should be avoided until the nasal lining has healed. This includes resisting the urge to pick at nasal crusts or scabs and refraining from excessive rubbing. After a bleeding episode, avoid vigorous activity, heavy lifting, or lowering the head below the heart for several hours, as these can increase blood pressure and cause bleeding to recur.
Warning Signs Indicating a Need for Medical Attention
While most bloody discharge during an illness is harmless, certain signs indicate the bleeding requires professional medical evaluation. Seek immediate medical care if the bleeding is heavy or profuse, not merely streaks or small clots, or if it lasts longer than 20 minutes despite continuous pressure. Bleeding that originates from the back of the nose, known as a posterior bleed, is often more severe and may present as blood flowing down the back of the throat.
Other symptoms alongside the bleeding warrant a doctor’s visit, such as feeling dizzy, faint, or weak, which could suggest significant blood loss. If the bloody discharge began following a direct blow or injury to the head or face, a medical assessment is necessary to rule out a fracture or serious trauma. If you are taking blood-thinning medications or have a known blood-clotting disorder, any nosebleed that does not stop quickly should be reported to a healthcare provider.