Keeping allergies at bay could be as simple as a spray

Image credit: AdobeStock/SydaProductions

When it rains, it pours. When our eyes water, our nose runs too. Rhinoconjunctivitis, the combined allergic conjunctivitis and allergic rhinitis, which is caused by immunoglobulin E (IgE)-mediated inflammation from environmental allergens such as pollen, dust, and dander, is a leading cause of watery eyes, runny nose, and postnasal drip.

The functions of our nasal passages are to warm and humidify the air we breathe, filter out allergens, dust, and microbes, regulate airflow, and produce nitric oxide, which helps dilate blood vessels to increase oxygenation in the blood. Postnasal drip is essentially any drainage of mucous from the nose or sinuses down the throat, contrasted with a runny nose, rhinorrhea, which is fluid running out the nostrils. There are other causes of a runny nose, including the common cold, cold air, or anything that irritates the nasal passages. Tissues (and maybe still handkerchiefs) are a necessity, but what happens when this lasts all day or even longer? There are many nasal spray options that we will review.

Nasal spray options

The first OTC nasal spray option is a simple saline nasal spray, which is a saltwater/saline solution that can rinse out irritants and break up and thin out mucus. The benefit of saline is that it is nonhabit forming and there is no rebound effect when discontinued. This may be most beneficial to an allergic patient who has had success using an oral antihistamine with or without a decongestant that can reduce the rhinitis/rhinorrhea.

The other nasal sprays can be placed into 4 categories: decongestants, antihistamines, steroids, and anticholinergics.

Decongestants

Decongestants constrict the blood vessels in the nose to reduce mucous production. These sprays are very fast acting and can clear a congested nasal passage and reduce nasal dripping. The OTC options are oxymetazoline hydrochloride (Afrin, Dristan, Sinex, Mucinex Sinus-Max) and phenylephrine hydrochloride (Neo-Synephrine). These are normally dosed for patients, who are older than 6 years and are not pregnant or breastfeeding, 2 times daily for 3 days, and then discontinued due to the risk of rebound congestion. Decongestants are discontinued in this manner for the same reasons that we educate our patients to stop ocular decongestants because of the risk of rebound redness. Humidifying and conditioning of inspired air through the nose is achieved through evaporation of water from the epithelial surface,¹ but if a nasal decongestant is used constantly, there will be no fluid present and blood vessels will not be able to expand to release nitric oxide. Constant decongestant use will affect the primary function of the nasal breathing pathway. However, if the decongestant is stopped, the tissue can become swollen and more congested, therefore leading to an increased risk of sinus infections. This is why advising caution and providing education are necessary when recommending this treatment.

Antihistamines

Antihistamine nasal sprays work by blocking histamine. This helps manage the symptoms of allergic rhinitis including sneezing, itching, rhinorrhea, and congestion. However, this will not help with congestion from the common cold. The adverse effects can be similar to but less severe than an oral antihistamine. It is still important to avoid alcohol and other depressants as antihistamines will cause increased drowsiness. Azelsastine has OTC (Astepro) and prescription (Astelin) options. Astepro is approved for patients older than 6 years for use 1 to 2 times per day.² Another prescription option is olopatadine (Patanase), which is approved for ages 12 and older.² These nasal sprays, which are safer to use for longer periods, may cause a bitter taste but no rebound congestion.

Another similar nasal spray is OTC cromolyn sodium (NasalCrom), which is a mast cell stabilizer, that stops allergic reactions before they start. This is approved for patients older than 2 years, is used 3 or 4 times daily (every 4 to 6 hours), and may take 1 to 2 weeks to take full effect.

Steroids

Steroid (corticosteroid) nasal sprays such as OTC fluticasone (Flonase and Flonase Sensimist), OTC mometasone furoate monohydrate (Nasonex), prescription beclomethasone (Beconase AQ, Qnasal) or OTC triamcinolone (Nasacort Allergy 24HR) inhibit IgE-dependent histamine release from mast cells and basophils in the nasal epithelium.³ The early stages of an allergic response are when sneezing, congestion, itchy nose, and rhinorrhea occur. Steroid nasal sprays can almost eliminate this response by reducing the nasal responsiveness to the histamine by reducing the expression of cytokines in the various effector cells.² Nasal sprays must be used consistently and they may take from 3 days to 2 weeks to work but they have fewer adverse effects than oral steroids.

Compared with decongestants, steroids are nonhabit forming and unlike antihistamines, steroids do not cause drowsiness. Nonetheless, as eye care providers we must know that steroids can carry ocular adverse effects such as a glaucoma risk due to increased IOP and cataract risk of posterior subcapsular opacification over time. Steroids can slow the growth rate of children, so their caretakers must discuss with their pediatrician whether the drugs are needed for longer than 2 months.

Steroids can also decrease wound healing, so it is not appropriate for individuals who had recent nasal surgery. Also be aware of what other steroid-containing medications the patient is taking, such as eye drops, eczema creams, asthma inhalers, injections, or tablets. Steroids will lessen the effects of treatments for fungal infections (any medication whose name ends in “zole”). Long-term intranasal steroid use can also cause changes in the nasal septum (bony cartilage, or osseocartilaginous, wall) over time. Sometimes a deviated septum is the cause of chronic rhinitis so septal surgery would be an appropriate and better form of management.⁴ Flonase is indicated for children aged 4 to 11 years (1 spray in each nostril daily) and ages 12 and older can use 1 or 2 sprays in each nostril daily as needed. Patients must pay attention to the dosage specified on the bottle. Keep in mind the different dosages of 27.5 mcg (Flonase Sensimist) versus 50 mcg (Flonase Allergy relief), as even the children’s dosage is still 50 mcg unless it is the Sensimist brand.

Nasonex and Nasacort are indicated for patients starting at age 2, and Beconase AQ indications are for those aged 6 and older.

Anticholinergics

The anticholinergic prescription nasal spray is ipratropium (Atrovent), which inhibits mucous secretion and is approved for rhinorrhea and postnasal drip. Anticholinergics block acetylcholine (ACh) from binding to its receptors and inhibit the parasympathetic nervous system, which controls the “rest and digest” functions of involuntary actions of smooth muscle.⁵ Atropine and cyclopentolate are examples of anticholinergic drugs. Inhaled Atrovent relaxes the muscles around the airway and is used to treat chronic obstructive pulmonary disease, emphysema, and chronic bronchitis. It does not relieve congestion or sneezing as well as the other options mentioned. Atrovent is indicated for ages 6 and older and is dosed as 2 sprays in each nostril 3 or 4 times daily. It comes in 2 dosages (0.03% and 0.06%); the lower dosage is for allergic rhinitis and is approved for use for 3 weeks. The higher dosage is for the common cold and is used only for 4 days. The most common adverse effects include nose bleeds and headache. Patients at risk of adverse effects are those with narrow-angle glaucoma, benign prostate hypertrophy, or dementia. Patients with dementia have reduced ACh in the brain and can become worse on anticholinergics.⁶

Alternative options for chronic cases

Now, what if this runny nose or postnasal drip has lasted for a year? Chronic allergic rhinitis and nonallergic rhinitis and rhinorrhea can affect a patient’s quality of life, and the above medications have limitations and adverse effects with their long-term use. There are now surgical options for these problems if a deviated septum is not the cause.

Figure 1. Trigeminal nerve divisions. Image courtesy of Wikemedia Commons/public domain.

Surgical options include cryotherapy and radiofrequency, which use minimally invasive techniques to ablate the posterior nasal nerves (neurolysis). The nasal cavities and septum are lined with a mucous membrane and vascularized by branches of the maxillary, facial, and ophthalmic arteries. The nasal cavity receives innervation via branches of the olfactory, cranial nerve (CN) I and 2 of the 3 branches of the trigeminal nerve, CN 5, ophthalmic (CN 5 V-1), and maxillary nerves (CN 5 V-2)⁷ (Figure 1). The parasympathetic nerves in the nasal mucosa of the posterior nasal nerve (PNN) (maxillary division of the trigeminal nerve) regulate mucous secretion and blood flow.⁸ The PNN is targeted in surgical treatments for chronic rhinitis. This alleviates stromal edema and manages the symptoms of chronic rhinitis.⁹ The ClariFix device by Stryker is an example of a cryotherapy device that provides focal, controlled freezing, and RhinAer is a stylus device that uses temperature-controlled radiofrequency energy to target the PNN (Figure 2).

Figure 2. Standard temperature-controlled radiofrequency ablation treatment sites. Image courtesy of RhinAer.

These 2 options only require local anesthesia and do not have serious adverse effects. In a meta-analysis of 788 patients, cryotherapy and radiofrequency ablation had positive effects on chronic rhinitis with significant improvements in symptoms and, therefore, quality of life.⁶ Some benefit was seen at 1 month. After 3 months, clinical improvement in all nasal symptoms was seen in 81.8% and 91.9% of patients who underwent cryotherapy and radiofrequency ablation, respectively.⁷ Cryotherapy benefits became more evident after 6 months and persisted for more than 9 months. Studies on radiofrequency ablation show improvement past 24 months post op.^.8 For allergic rhinitis, patients will still require oral antihistamines.

No ophthalmic adverse effects, including dry eye, have been reported in detail. One could deduce that the risk would increase if the ophthalmic division of the trigeminal nerve is ablated.

References:

1. Naclerio RM, Pinto J, Assanasen P, Baroody FM. Observations on the ability of the nose to warm and humidify inspired air. Rhinology. 2007;45(2):102-111. PMID: 17708456.

2. Smedley T, Billingsley A. Steroids, antihistamines, and decongestants: choosing the best nasal spray for allergies. GoodRX. June 3, 2024. Accessed January 10, 2025. https://www.goodrx.com/conditions/allergies/nasal-spray#antihistamine-sprays

3. Mygind N, Nielsen LP, Hoffmann HJ, et al. Mode of action of intranasal corticosteroids. J Allergy ClinImmunol. 2001;108(suppl 1):S16-25doi:10.1067/mai.2001.115561

4. Alghamdi FS, Albogami D, Alsurayhi AS, et al. Nasal septal deviation: a comprehensive narrative review. Cureus. 2022;14(11):e31317. doi:10.7759/cureus.31317

5. Ghossein N, Kang M, Lakhkar AD. Anticholinergic medications. In: StatPearls. StatPearls Publishing;2023. Accessed December, 4, 2024. https://www.ncbi.nlm.nih.gov/books/NBK555893/

6. Miller CA. Anticholinergics: the good and the bad. Geriatr Nurs. 2002;23(5):286-287. doi:10.1067/mgn.2002.128791

7. Chapter 23. Nasal Cavity. In: Morton DA, Foreman K, Albertine KH. eds. The Big Picture: Gross Anatomy. The McGraw-Hill Companies; 2011. Accessed December 16, 2024. https://accesspharmacy.mhmedical.com/content.aspx?bookid=381&sectionid=40140031

8. Kang YJ, Stybayeva G, Hwang SH. Comparative effectiveness of cryotherapy and radiofrequency ablation for chronic rhinitis: a systematic review and meta-analysis. Clin Exp Otorhinolaryngol. 2023;16(4):369-379. doi:10.21053/ceo.2023.01214

9. Ehmer D, McDuffie CM, McIntyre JB, et al. Long-term outcomes following temperature-controlled radiofrequency neurolysis for the treatment of chronic rhinitis. Allergy Rhinol (Providence). 2022;13:21526575221096045. doi:10.1177/21526575221096045