Solutions for nasal irrigation

The solution used to perform nasal irrigation has a huge effect on the comfort of the procedure as well as the health benefits obtained. All solutions will, of course, mechanically clear out excess mucus at the time nasal irrigation is performed, but nasal irrigation can have a much longer lasting impact depending on the solution used. There are two main ways in which irrigation solutions vary, the tonicity (salinity) and which (if any) additives are added.

Tonicity

The tonicity (salt concentration) has a huge impact on the comfort of performing nasal irrigation. Many people are put off of the idea of nasal irrigation simply because they have had water go up their nose when swimming and know that it hurts. The reason that it hurts though is that the salt concentration of swimming pool water is much lower than that of human tissue. Solutions which match the salinity of human tissue (~0.9%) are known as isotonic and solutions of lesser or greater concentration are known as hypotonic and hypertonic respectively.

Hypotonic solutions can be very uncomfortable, have no known health benefits and are therefore not recommended. Solutions traditionally used for jala-neti are roughly isotonic but hypertonic solutions can also be used.

Isotonic

An isotonic saline solution is a solution with approximately the same salt concentration as human blood (~0.9%). This makes it the most comfortable solution to use. Isotonic solutions are very safe to use, being associated with few side effects,[1] fewer even, than hypertonic solutions.

There is evidence that nasal irrigation with isotonic saline solution can reduce some of the symptoms of sinusitis, namely nasal secretions and post-nasal drip.[2] Nasal irrigation with isotonic saline has been put forward as an effective treatment for chronic sinusitis[3] and has also been found to reduce sino-nasal symptoms from air-born irritants such as wood dust[1, 4]. It's unclear whether isotonic saline improves mucociliary clearance after use, as clinical studies have found conflicting results.[5, 6] Nasal irrigations with isotonic saline have been shown to decrease the concentrations of inflammatory mediators (histamine and leukotriene C4) in patients with allergic rhinitis for hours after each irrigation (six and four respectively).[7]

Pros:
  • Most comfortable
  • Associated with few side-effects
Cons:
  • Less effective for treating sino-nasal conditions
  • Unclear whether mucociliary clearance is improved
  • Not believed to actively reduce inflammation

Hypertonic

Hypertonic saline has a greater salt concentration than human blood. It is less comfortable to use than isotonic solutions and is known to cause a stinging or burning sensation in some people.[8, 9] It is also associated with more side effects than isotonic saline, including:[9]

  • Nasal irritation
  • Headache
  • Tearing
  • Nosebleeds
  • Nasal drainage

These side-effects are rare, and considered to be minor. (Not so bothersome as to cause people to cease treatment.) They can also be reduced or eliminated by reducing either the frequency of irrigations or the salt concentration.

On the other hand, nasal irrigation with hypertonic solutions is known to have far greater health benefits compared to isotonic saline. Hypertonic solutions are effective for treating a variety of sino-nasal conditions, including allergic rhinitis,[10, 11, 12, 13, 14] ageing rhinitis,[11] atrophic rhinitis[10] and sinusitis[2, 9, 10, 15, 16]. In addition to the sinusitis symptoms alleviated by isotonic saline (nasal secretions and post-nasal drip), hypertonic solutions can also alleviate cough.[2] Hypertonic solutions have also been able to alleviate the nasal congestion, headaches and frontal pain and pressure associated with sinusitis.[9] Nasal irrigations with hypertonic saline have also been shown to reduce the use of medications such as anti-biotics and nasal sprays in patients with sinusitis,[9, 17] and to improve sinus-related quality-of-life (QOL) scores[9, 15]. Nasal irrigation with hypertonic saline has been shown to improve mucociliary clearance,[5, 6, 18, 19, 20] mucus rheology[18, 21] and may reduce inflammation.

Pros:
  • More effective for treating sino-nasal conditions
  • Improves mucociliary clearance
  • May actively reduce inflammation
Cons:
  • Less comfortable
  • Associated with more side-effects

Comparison table

Isotonic Hypertonic
Most comfortable Yes No
Least side-effects Yes No
Clears away mucus Yes Yes
Effective for allergic rhinitis Yes Yes
Improves mucociliary clearance No Yes
Believed to reduce inflammation No Yes
Most effective for sino-nasal symptom relief No Yes

Additives

pH buffers

Because saline is slightly acidic (isotonic solutions have a pH of around 6.4) many people believe it is best to buffer the saline solution to be slightly alkaline so that it is more similar to sino-nasal mucus (pH ~8). This can be achieved by adding a pH buffering agent to the solution such as sodium bicarbonate (baking soda). The addition of a buffering agent does not seem to affect mucociliary clearance[3, 19] but may reduce discomfort in some people.

Anti-septic & mucolytic agents

One study[22] has investigated the effect of adding anti-septic and mucolytic (breaks down thick mucus) agents to saline. They tested saline solutions with added benzododecinium (anti-septic) and oleosorbate (mucolytic) on patients who had undergone endoscopic surgery for nasal polyps but found no significant effect on either crust removal of the severity of reported symptoms when compared to saline without the additives.

Ephedrine

Ephedrine, amongst other things, is a vasoconstrictor (causes blood vessels to narrow) and therefore can be administered topically to the nasal passages to work as a decongestant. One study[23] investigated the efficacy of isotonic saline with added ephedrine (1%) on sufferers of allergic rhinitis, and found a significantly greater improvement in symptom scores compared to normal isotonic saline without added ephedrine. The study doesn't advocate regular use of ephedrine solutions for prolonged periods though. When administered systemically and in high doses, ephedrine can have serious side effects and is only available on prescription in the UK.

Table salt additives

Table salt usually contains anti-caking agents. It is not recommended to perform nasal irrigation with a solution containing anti-caking agents and so care must be taken when choosing a salt. It is also important that the salt is non-iodised. Sea, picking and kosher salt should all be free of these additives and suitable for nasal irrigation solutions.

References
[1]
M. Holmstrom, G. Rosen, and L. Wahlander. Effect of nasal lavage on nasal symptoms and physiology in wood industry workers. Rhinology, 35(3):108-12, 1997.
[2]
D. Shoseyov, H. Bibi, P. Shai, N. Shoseyov, G. Shazberg, and H. Hurvitz. Treatment with hypertonic saline versus normal saline nasal wash of pediatric chronic sinusitis. J Allergy Clin Immunol, 101(5):602-5, 1998.
[3]
G. Bachmann, G. Hommel, and O. Michel. Effect of irrigation of the nose with isotonic salt solution on adult patients with chronic paranasal sinus disease. Eur Arch Otorhinolaryngol, 257(10):537-41, 2000.
[4]
S. J. Rabone and S. B. Saraswati. Acceptance and effects of nasal lavage in volunteer woodworkers. Occup Med (Lond), 49(6):365-9, 1999.
[5]
E. Daviskas, S. D. Anderson, I. Gonda, S. Eberl, S. Meikle, J. P. Seale, and G. Bautovich. Inhalation of hypertonic saline aerosol enhances mucociliary clearance in asthmatic and healthy subjects. Eur Respir J, 9:725-32, 1996.
[6]
A. R. Talbot, T. M. Herr, and D. S. Parsons. Mucociliary clearance and buffered hypertonic saline solution. Laryngoscope, 107(4):500-3, 1997.
[7]
J. W. Georgitis. Nasal hyperthermia and simple irrigation for perennial rhinitis. changes in inflammatory mediators. Chest, 106(5):1487-92, 1994.
[8]
P. Adam, M. Stiffman, and R. Blake. A clinical trial of hypertonic saline nasal spray in subjects with the common cold or rhinosinusitis. Arch Fam Med, 7(1):39-43, 1998.
[9]
D. Rabago, A. Zgierska, M. Mundt, B. Barrett, J. Bobula, and R. Maberry. Efficacy of daily hypertonic saline nasal irrigation among patients with sinusitis: a randomized controlled trial. J Fam Pract, 51(12):1049-55, 2002.
[10]
J. Nuutinen, E. Holopainen, T. Haahtela, P. Ruoppi, and M. Silvasti. Balanced physiological saline in the treatment of chronic rhinitis. Rhinology, 24(4):265-9, 1986.
[11]
L. T. Tomooka, C. Murphy, and T. M. Davidson. Clinical study and literature review of nasal irrigation. Laryngoscope, 110(7):1189-93, 2000.
[12]
W. Garavello, M. Romagnoli, L. Sordo, R. M. Gaini, C. Di-Berardino, and A. Angrisano. Hypersaline nasal irrigation in children with symptomatic seasonal allergic rhinitis: a randomized study. Pediatr Allergy Immunol, 14(2):140-3, 2003.
[13]
W. Garavello, F. Di-Berardino, M. Romagnoli, G. Sambataro, and R. M. Gaini. Nasal rinsing with hypertonic solution: an adjunctive treatment for pediatric seasonal allergic rhinoconjunctivitis. Int Arch Allergy Immunol, 137(4):310-4, 2005.
[14]
S. Cordray, J. B. Harjo, and L. Miner. Comparison of intranasal hypertonic dead sea saline spray and intranasal aqueous triamcinolone spray in seasonal allergic rhinitis. Ear Nose Throat J, 84(7):426-30, 2005.
[15]
M. Taccariello, A. Parikh, Y. Darby, and G. Scadding. Nasal douching as a valuable adjunct in the management of chronic rhinosinusitis. Rhinology, 37(1):29-32, 1999.
[16]
D. Rabago, T. Pasic, A. Zgierska, M. Mundt, B. Barrett, and R. Maberry. The efficacy of hypertonic saline nasal irrigation for chronic sinonasal symptoms. Otolaryngol Head Neck Surg, 133(1):3-8, 2005.
[17]
D. G. Heatley, K. E. McConnell, T. L. Kille, and G. E. Leverson. Nasal irrigation for the alleviation of sinonasal symptoms. Otolaryngol Head Neck Surg, 125(1):44-8, 2001.
[18]
M. Robinson, A. L. Hemming, J. A. Regnis, A. G. Wong, D. L. Bailey, G. J. Bautovich, M. King, and P. T. Bye. Effect of increasing doses of hypertonic saline on mucociliary clearance in patients with cystic fibrosis. Thorax, 52(10):900-3, 1997.
[19]
J. J. Homer, R. J. England, A. D. Wilde, G. R. Harwood, and N. D. Stafford. The effect of pH of douching solutions on mucociliary clearance. Clin Otolaryngol Allied Sci, 24(4):312-5, 1999.
[20]
J. J. Homer, A. C. Dowley, L. Condon, P. El-Jassar, and S. Sood. The effect of hypertonicity on nasal mucociliary clearance. Clin Otolaryngol Allied Sci, 25(6):558-60, 2000.
[21]
P. J. Wills, R. L. Hall, W. Chan, and P. J. Cole. Sodium chloride increases the ciliary transportability of cystic fibrosis and bronchiectasis sputum on the mucus-depleted bovine trachea. J Clin Invest, 99(1):9-13, 1997.
[22]
D. Pigret and R. Jankowski. Management of post-ethmoidectomy crust formation: randomized single-blind clinical trial comparing pressurized seawater versus antiseptic/mucolytic saline. Rhinology, 34(1):38-40, 1996.
[23]
W. A. Shaikh. Ephedrine-saline nasal wash in allergic rhinitis. J Allergy Clin Immunol, 96(5 Pt 1):597-600, 1995.