Nasal irrigation is widely used as an adjunct to relieve rhinitis, sinusitis, and other conditions due to its ease of use and low cost. However, seemingly mild saline solution, if used improperly, can lead to risks such as nasal mucosal damage, otitis media, and even the spread of infection.
Nasal Mucosal Damage
High-concentration saline solution damages the mucosal barrier
Normal nasal mucosa is composed of ciliated cells, mucous glands, and immune cells, forming a "mucociliary clearance system." When using saline solution with a concentration exceeding 3%, the high osmotic pressure directly causes dehydration of mucosal cells, disrupting ciliary movement. A controlled trial involving 200 rhinitis patients showed that those who used 3% hypertonic saline irrigation for 7 consecutive days had a 42% decrease in nasal mucosal ciliary movement frequency compared to the 0.9% saline group, and ciliary function was not fully restored even 3 hours after irrigation.
Excessive Flushing Pressure Causing Mechanical Injury
When using a syringe or high-pressure irrigator, if the water flow rate is too fast (exceeding 15 ml/s), it may directly impact the surface of the nasal turbinates, causing tearing of the nasal mucosa. Children are at higher risk due to their narrower nasal cavities. Clinical statistics show that 65% of nosebleeds caused by excessive flushing pressure occur in children under 12 years old.
Prevention Recommendations:
Prioritize squeeze-type or electric low-pressure irrigators (pressure ≤12 kPa);
Adults should flush with 200-300 ml per flush, children half that amount;
Keep breathing through your mouth during flushing and avoid swallowing.
Risk of Otitis Media
Incorrect Posture Leading to Fluid Backflow
The nasal cavity and middle ear are connected by the Eustachian tube. Children's Eustachian tubes are shorter and horizontal. If the head is tilted back or the nose is blown forcefully during flushing, saline may enter the middle ear cavity through the Eustachian tube. A study of 500 children found that incorrect flushing posture led to an otitis media incidence rate of 3.2%, with children under 7 years old accounting for 85% of these cases.
Pathogen Invasion and Infection
If the rinsing water is not thoroughly sterilized (e.g., using unboiled tap water), it may carry pathogens such as amoebae and Streptococcus pneumoniae.
Prevention Recommendations:
Stand upright with your head tilted forward at a 45° angle during rinsing;
Use medical-grade 0.9% saline solution or boiled and cooled sterile water;
Keep your head upright for 15 minutes after rinsing and avoid blowing your nose immediately.
Infection Spread
Increased Risk in Postoperative Patients
Patients who have undergone nasal surgery (such as septoplasty or sinus surgery) have open wounds on the nasal mucosa, and rinsing may introduce bacteria into deeper tissues. Clinical statistics show that patients who undergo nasal rinsing within 7 days post-surgery have an 18% higher infection rate than those who do not.
Fatal Risk in Immunocompromised Individuals
In individuals with HIV/AIDS, diabetes, or those using long-term immunosuppressants, nasal rinsing may become a "breakthrough" for pathogen invasion.
Protective Recommendations: Post-operative patients should use sterile saline solution for rinsing under the guidance of a doctor; For immunocompromised patients, ensure the water is sterile before rinsing and use antibiotic nasal drops afterward; Irrigation instruments should be boiled daily for sterilization to avoid cross-contamination.
The "Opposite Effects" of Long-Term Dependence
Ciliary Movement Inhibition
The nasal mucus layer is maintained by the continuous movement of ciliary cells. Frequent rinsing may dilute the mucus, weakening the efficiency of ciliary movement. Animal experiments showed that mice rinsed with saline solution three times daily had a 28% decrease in nasal mucosal ciliary movement frequency compared to the control group, and this decrease did not recover even 6 hours after rinsing.
Mucosal Dryness and Crusting
Long-term rinsing may disrupt the "moisture-dryness" balance of the nasal mucosa. A follow-up study of 100 patients with chronic rhinitis showed that those who rinsed daily for three consecutive months had a 41% higher incidence of nasal mucosal dryness than those who did not rinse, and 23% experienced nasal bleeding.
Protective Recommendations: Irrigate 1-2 times daily, no more than 3 times during acute attacks; After rinsing, apply petroleum jelly or nasal moisturizing gel to the nasal vestibule; Maintain indoor humidity at 40%-60% and reduce dust exposure.
Contraindications for Special Populations
Infants and Young Children: Nasal irrigation is prohibited for infants under 1 year old whose nasal structures are not fully developed; children aged 1-3 years should use a dedicated nasal irrigator under the guidance of a doctor.
Individuals with Coagulation Disorders: Hemophiliacs and those on long-term anticoagulant medications have a 3 times increased risk of nasal bleeding after irrigation.
Patients with Skull Base Fractures: Irrigation may lead to cerebrospinal fluid rhinorrhea, causing intracranial infection.
Patients with Acute Otitis Media: Irrigation may worsen ear pain and hearing loss.
Saline irrigation is not a "cure-all"; its risks stem from ignoring physiological mechanisms. The tolerance threshold for saline varies significantly across different parts of the body, from the nasal mucosa to the middle ear cavity. Only by following medical evidence and abandoning the misconceptions that "the higher the concentration, the more effective" and "the more frequent the rinsing, the better," can saline truly become a safe and effective adjunctive treatment.
