Clinical Studies
Aardvark Medical is currently conducting clinical studies. If you interested in conducting or participating in a study please contact director@aardvarkmedical.com.
Commercial availability in the U.S. is pending FDA clearance
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Clinical References
Over the counter medications
Smith, M. and W. Feldman (1993). “Over-the-counter cold medications. A critical review of clinical trials between 1950 and 1991.” JAMA 269(17): 2258-63.
There is no good evidence showing efficacy of over-the-counter medications in preschool children.
Ames, J. T., G. F. Hayden, et al. (1982). “Parents’ conception of their use of over-the-counter medicines.” Clin Pediatr 21(5): 298-301.
Parents are more willing to medicate their children for fever than for nasal congestion, especially to children under 2 years of age.
Suh, S., K. Chon, et al. (1995). “Effects of topical nasal decongestants on histology of nasal respiratory mucosa in rabbits.” Acta Otolaryngol 115(5): 664-71.
Use of topical decongestants for more than two weeks not only damages the cilia that line the nasal and sinus cells, but also causes inflammation in the nasal respiratory mucosa.
Bryant, B. and H. Mason (1983). “Nonprescription drug use among hospitalized pediatric patients.” Am J Hosp Pharm 40(10): 1669-73.
Physician recommendations were noted as an important factor in the selection of non-prescription products, followed in importance by pharmacists and other health-care professionals. Those sources also ranked higher than other recommendation sources such as television, radio, or printed advertisements.
Paul, I., K. Yoder, et al. (2004). “Effect of dextromethorphan, diphenhydramine, and placebo on nocturnal cough and sleep quality for coughing children and their parents.” Pediatrics 114(1): e85-e90.
Common over-the-counter medications given to children for coughing secondary to upper respiratory infections do not result in better sleep for the children or their parents compared to placebo. Dextromethorphan did cause insomnia and diphenhydramine caused drowsiness.
Gunn (2001). “Toxicity of over-the-counter cough and cold medications.” Pediatrics 108: e52.
This is a summary view of over-the-counter medications’ expense and potential morbidity and mortality. It reiterates the American Academy of Pediatric’s view that physicians should educate on their patients on the lack of benefit and known risks of OTC cold and cough preparations.
Taverner, D., J. Latte, et al. (2004). “Nasal decongestants for the common cold.” Cochrane Database Syst Rev 3(CD001953).
There is insufficient evidence to show that oral or nasal decongestants work in children under the age of 12.
Krouse, J. (1999). “Patient use of traditional and complimentary therapies in treating rhinosinusitis before consulting an otolaryngologist.” Laryngoscope 109(8): 1223-1227.
Patients use both traditional and complementary therapies before seeking care of an otolaryngologist for allergies and sinusitis.
Shroeder, K. and T. Fahey (2004). “Over-the-counter medications for acute cough in children and adults in ambulatory settings.” Cochrane Database Syst Rev 18(4): CD001831.
There is no good evidence for or against the use of OTC medicines for an acute cough.
Shroeder, K. and T. Fahey (2002). “Should we advise parents to administer over the counter cough medicines for acute cough? Systematic review of randomized controlled trials.” Arch Dis Child 86(3): 170-175.
OTC cough medicines do not appear more effective than placebo in relieving symptoms of acute cough.
Flores, G., M. Abreu, et al. (2003). “Keeping children out of hospitals: parents’ and physicians’ perspectives on how pediatric hospitalizations for ambulatory care-sensitive conditions can be avoided.” Pediatrics 112(5): 1021-30.
Pediatric hospitalizations can be avoided if parents and children were better educated about the child’s condition and use of OTC and prescription medications.
Saline irrigation
Tomooka, L. T., C. Murphy, et al. (2000). “Clinical Study and Literature Review of Nasal Irrigation.” The Laryngoscope 110: 1189-1193.
Nasal irrigation effectively improves symptoms and health status in patients with sinonasal disease.
Talbot, A. R., T. M. Herr, et al. (1997). “Mucociliary Clearance and Buffered Hypertonic Saline Solution.” The Laryngoscope 107: 500-503.
Buffered hypertonic saline irrigation improved mucociliary transit times, whereas normal saline had no effect.
Bounmany, K., B. Keojampa, et al. (2004). “Effects of buffered saline solution on nasal mucociliary clearance and nasal airway clearance.” Otolaryngology 131(5): 679-682
Both formulations improve mucociliary flow, with hypertonic saline showing greater efficacy. Neither significantly changed nasal airway patency.
Ragabo, D., T. Pasic, et al. (2005). “The efficacy of hypertonic saline nasal irrigation for chronic sinonasal symptoms.” Otolaryngol Head Neck Surg 133(1): 3-8.
Patients with chronic sinonasal symptoms who regularly used hypertonic saline irrigation showed an improved quality of life as well as scores on a number of standardized indices.
Unal, M., K. Gogur, et al. (2001). “Ringer-Lactate solution versus isotonic saline solution on mucociliary function after nasal septal surgery.” Journal of Laryngology and Otology 115: 796-797.
Mucociliary transport time was better when Ringer-Lactate solution was used than with isotonic saline solution.
Wabnitz, D. A. and P. J. Wormald (2005). “A blinded, randomized, controlled study on the effect of buffered 0.9% and 3% sodium chloride intranasal sprays on ciliary beat frequency.” Laryngoscope 155(5): 803-5.
Hypertonic saline (3%) resulted in better ciliary beat frequency than did normal saline (.9%). This difference was not seen after 60 minutes.
Friedman, M., R. Vidyasagar, et al. (2006). “A randomized, prospective, double-blind study on the efficacy of Dead Sea nasal irrigations.” Laryngoscope 116(6): 878-882.
Dead sea salt irrigation was as efficacious as hypertonic saline irrigation in regards to improvement in quality of life, but was better for symptom improvement.
Bounmany, K., B. Keojampa, et al. (2004). “Effects of buffered saline solution on nasal mucociliary clearance and nasal airway clearance.” Otolaryngology 131(5): 679-682.
While both preparations improved saccharine clearance times, hypertonic saline showed more improvement than normal saline. Neither had an adverse effect on nasal patency.
Cordray, S., J. Harjo, et al. (2005). “Comparison of intranasal hypertonic dead sea saline spray and intranasal aqueous triamcinolone spray in seasonal allergies.” Ear Nose Throat Journal 84(7): 426-430.
Dead Sea saline solution can be an effective alternative in mild-moderate allergic rhinitis based on the Rhinoconjuncitivits Quality of Life Questionnaire scores.
Methods of irrigation and aspiration
Passali, D., V. Damiani, et al. (2005). “Atomized nasal douche vs nasal lavage in acute viral rhinitis.” Arch Otolaryngol Head Neck Surg 131(9): 788-90.
Irrigant atomization was superior to high volume lavage (water stream) in improving symptoms, mucociliary transport nasal patency and volume.
Olson, D., B. Rasgon, et al. (2002). “Radiographic comparison of three methods for nasal saline irrigation.” Laryngoscope 112(8): 1394-1398.
Based on radiolabeled exams, nebulized solution was less effective than positive pressure lavage in penetrating the sinuses. This study had eight patients and did not reveal the particle size of the nebulized irrigant that contained contrast material.
Taccariello, M., A. Parikh, et al. (1999). “Nasal douching as a valuable adjunct in the management of chronic rhinosinusitis.” Rhinology 37(1): 29-32.
The nasal douche (high volume) improved endoscopic appearance and the saline spray (atomization) improved quality of life.
Davidson, T. (2000). “Clinical study and literature review of nasal irrigation.” Laryngoscope 110.
Daily pulsatile irrigation patients had excellent relief from sinusitis and allergies.
Mabry, R. (1993). “Therapeutic agents in the medical management of sinusitis.” Otolaryngologic Clinics of North America 26(4): 561.
Pulsatile sinus irrigation benefits those with postnasal drip and postoperative cleansing needs.
Scott, C. (1993). “Pediatric sinusitis.” Otolaryngologic Clinics of North America 26(4): 623-638.
Pulsatile irrigation with normal saline is effective in pediatric sinusitis, even in the absence of antibiotics.
Viral colds/ bronchiolitis
Steiner, R. P. (2004). “Treating acute bronchiolitis associated with RSV.” Am Fam Physician 69(2): 325-330.
This is a summary statement from the American Academy of Family Physicians which shows clear evidence of efficacy of supportive measures. These include nasal irrigation/aspiration, hydration, and oxygen delivery.
AAP (2007). Common Colds and Young Children. American Academy of Pediatrics.
This American Academy of Pediatric’s parental web site recommends the use of saline irrigation for children’s congestion.
WrongDiagnosis (2006). Prevalence and Incidence of Common Cold, www.wrongdiagnosis.com.
Children get 6-10 colds/year. Incidence is 23%. Prevalence is one billion episodes/year.
Papsin, B. and A. McTavish (2003). “Saline nasal irrigation: Its role as an adjunct treatment.” Can Fam Physician 49: 168.
Saline irrigation in children with colds resulted in fewer physician visits.
Bennion, K. and John W. Salyer (2000). “Nasopharyngeal suctioning and albuterol in bronchiolitis.” Respiratory Care 45.
Intervention with nasopharyngeal suctioning and saline irrigation improved respiratory scores in babies with bronchiolitis. It also decreased the need for further interventions such as albuterol.
Gwaltney, J., J. Hendley, et al. (2000). “Nose Blowing propels nasal fluid into the paranasal sinuses.” Clinical infectious diseases 30(2): 387-391.
A single nose blow can generate 66mmHg pressure and propel mucous into the sinuses, possibly exacerbating a simple viral upper respiratory infection.
T Zemlicka-Dunn, J. B. (2001). “The association between nasopharyngeal suction and oxygen requirement in bronchiolitis.” Respiratory Care 46(10): 1071.
Nasopharyngeal suctioning effected a decrease need for oxygen in babies with bronchiolitis.
Glenna-McKinley, J. B. (2001). “The effects of NP suctioning on symptom scores in bronchioilitis patients.” Respiratory Care 46(10): 1071.
Nasopharyngeal suctioning resulted in improvement in a standardized bronchiolitis score for babies with bronchiolitis.
Bennion, K., J. Ballard, et al. (2003). “Comparing the use of nasopharyngeal suctioning with a catheter vs. olive-tipped device in suctioning bronchiolitis patients at two regional medical centers in Utah.” Respiratory Care 48(11): 1075.
Suctioning the nose with a catheter is superior to using an olive-tip device evaluated by a standardized bronchiolitis score.
Seasonal Allergies
Garavello, W., M. Romagnoli, et al. (2004). “Hypersaline nasal irrigation in children with seasonal allergic rhinitis: a randomized study.” Pediatr Allergy Immunol 14(2): 140-3.
Regular use of nasal irrigation decreased severity of symptoms associated with seasonal allergies as well as the use of oral antihistamines.
Nathan, R. (2007). “The burden of allergic rhinitis.” Allergy Asthma Proc 28(1): 3-9.
Nasal congestion associated with allergic rhinitis has a profound effect on sleep disturbances, learning, behavior and attention. It results in 3.5 million lost workdays and 2 million lost schooldays annually.
Garavello, W., R. D. Berardino, et al. (2005). “Nasal rinsing with hypertonic solution: an adjunctive treatment for pediatric seasonal allergic rhinoconjunctivitis.” Int Arch Allergy Immunol 137(4): 310-4.
The mean rhino-conjunctivitis score in those receiving nasal irrigation was much lower than in the control group during a pollen season.
Sly, R. (1999). “Changing prevalence of allergic rhinitis and asthma.” Annals of Allergy, Asthma, and Immunology 82(3): 233-252.
Current prevalence of allergic rhinitis at 16 years of age in cohorts of British children born in 1958 and 1970 increased from 12% in the earlier cohort to 23% in the latter cohort.
Faber, J. (2006) “Allergists explore rising prevalence and unmet needs attributed to allergic rhinitis.” American College of Allergy, Asthma, and Immunology Online
There is epidemiological evidence that the prevalence of allergic rhinitis is rising, and some reports suggest a 100% increase in each of the past three decades.
Kulig, M., U. Klettke, et al. (2000). “Development of seasonal allergic rhinitis during the first 7 years of life.” J Allergy Clin Immunology 106(5): 832-839.
This German study shows that up to 7 years of age, seasonal allergic rhinitis developed in 15% of the children, increasing rapidly after the second year of life.
Crystal-Peters, J., W. Crown, et al. (2000). “The cost of productivity losses associated with allergic rhinitis.” Am J Manag Care 6(3): 373-378.
The National Health Interview Survey found the most significant productivity losses resulted from loss of at-work productivity and were estimated to be as high as $4.6 billion/year.
Law, A., S. Reed, et al. (2003). “Direct costs of allergic rhinitis in the United States: estimates from the 1996 Medical Expenditure Panel Survey.” J Allergy Clin Immunology 111(2): 296-300.
In 1996, 7.7% of the population had allergic rhinitis and direct costs of this were $3.4 billion including prescription medications and physician visits.
Georgitis, J. (1994). “Nasal Hyperthermia and simple irrigation for perennial rhinitis.” Chest 106(5): 1487-1491.
The use of simple nasal irrigation reduced the amount of inflammatory mediators in allergic rhinitis.
Sinusitis
Wald, E. (2001). “Clinical Practice Guidelines: Management of Sinusitis.” Pediatrics 108(3): 798-808.
The American Academy of Pediatrics makes no formal recommendations on the use of saline for sinusitis based on lack of proper inclusive studies. However, the guideline does state that saline likely prevents crust formation and liquefies secretions, as well as possibly acting as a vasoconstrictor of nasal blood flow.
Metson, R. and R. Sindwani (2007). Chronic Sinusitis. UpToDate.com
Nasal irrigation is extremely helpful in the treatment of those with sinusitis.
Nash, D. and W. Wald (2001). “Sinusitis.” Pedatrics in Review 22(4): 111-117.
Nasal saline irrigation has been shown to have a positive effect and is an inexpensive way initiate decongestion. This article does admit the need for further prospective studies to evaluate saline irrigation in pediatric sinusitis.
Wald, E. (2007). Microbiology and treatment of acute bacterial sinusitis in children, UpToDate.
Saline may be helpful in preventing crust formation and liquefying sinus secretions, and despite unproven benefits, the therapy is safe and cheap.
Rabago, D., A. Zgierska, et al. (2002). “Efficacy of daily hypertonic saline nasal irrigation among patients with sinusitis: a randomized controlled trial.” J Fam Pract 51(12): 1049-1055.
Daily hypertonic saline nasal irrigation improved sinus-related quality of life, decreased symptoms, and decreased antibiotic use in patients with frequent sinusitis.
Rabago, D., B. Barrett, et al. (2006). “Qualitative aspects of nasal irrigation use by patients with chronic sinus disease in a multimethod study.” Annals of Family Medicine 4(4): 295-301.
Interviews with patients who had used hypertonic saline irrigation revealed that it improved self-management of their sinus symptoms and gave rapid improvement in quality of life.
Shoseyov, D., H. Bibi, et al. (1998). “Treatment with hypertonic saline versus normal saline nasal wash of pediatric chronic sinusitis.” J Allergy Clin Immunol 101: 602-5.
Both normal saline and hypertonic saline decreased postnasal drip, but only hypertonic saline improved cough and radiologic scores.
Taccariello, M., A. Parikh, et al. (1999). “Nasal douching as a valuable adjunct in the management of chronic rhinosinusitis.” Rhinology 37(1): 29-32.
Nasal irrigation improved quality of life in patients with chronic sinusitis
Scott, C. (1993). “Pediatric sinusitis.” Otolaryngologic Clinics of North America 26(4): 623-638.
Pulsatile irrigation with normal saline is effective in pediatric sinusitis, even in the absence of antibiotics.
Pollution
Masur, L. and J. Kim (2006). “Spectrum of noninfectious health effects from molds.” Pediatrics 118(6): e1909-e1926.
This technical report from the American Academy of Pediatrics notes that the most common adverse health effect associated with mold exposure is allergic rhinitis. Additionally, 5-10% of patients with chronic sinusitis have a fungal etiology.
Boutin-Forzano, S., Y. Hammou, et al. (2005). “Air pollution and atopy.” Allerg Immunol 37(1): 11-6.
Air pollutants, especially diesel exhaust particulates, are able to trigger an IgE-response and allergic sensitization with the development of atopic diseases.
CDC (2006). Smoking prevalence among U.S. adults. Tobacco information and prevention source (TIPS).
21% (45 million) of adults in the United States are current smokers.
Vander, E., T. Wyatt, et al. (2005). “Smoke exposure exacerbates an ethanol-induced defect in mucociliary clearance of Streptococcus pnuemoniae.” Alcohol Clin Exp Res 29(5): 882-7.
A rat model shows decreased mucociliary clearance when exposed to tobacco smoke. This could lead to poor filtration of infectious agents otherwise cleared by the nasal cells.
Vanscheeuwijck, P., A. Teredesai, et al. (2002). “Evaluation of potential side effects of ingredients added to cigarrettes. Part 4: subchronic inhalation toxicity.” Food Chem Toxicol 40(1): 113-31.
In a rat model, tobacco smoke causes pre-cancerous alterations in the cells lining the nose and sinuses.
Vent, J., A. Robinson, et al. (2004). “Pathology of the olfactory epithelium: smoking and ethanol exposure.” Laryngoscope 114(8): 1383-8.
Tobacco smoke alters olfactory sensory neurons which results in smell loss.
Bascom, R., J. Kesavanathan, et al. (1995). “Sidestream tobacco smoke exposure acutely alters human nasal mucociliary clearance.” Environ Health Perspect 103(11): 1026-30.
Tobacco smokers have abnormal nasal mucociliary clearance
Lin, M., D. Stieb, et al. (2005). “Coarse particulate matter and hospitalization for respiratory infection for respiratory infections in children younger than 15 years in Toronto: A case crossover analysis.” Pediatrics 116(2): e235-e240.
Ambient particulate matter and gaseous pollutants exacerbates respiratory diseases in children.
Sunderman, F. (2001). “Nasal toxicity, carcinogenicity, and olfactory uptake of metals.” Annals of Clinical and Laboratory Science 31: 3-24.
Occupational exposures to metal dust and aerosol inhalation can cause loss of olfactory acuity, mucosal ulcers, or sinonasal cancer.
Hudson, R., L. Arrioila, et al. (2006). “Effect of air pollution on olfactory function in residents of Mexico City.” Chemical Senses 31 (1): 79-85.
Air pollution in Mexico City is shown to adversely affect olfactory function.