Here in the Midwest, this diagnosis is often kicking into gear at this point; as the weather warms up in the springtime. However, this year due to the very mild winter we had, I saw persistent symptoms all winter long.
Today we are talking about the treatment of allergic rhinitis.
We will discuss
- Intranasal steroids:
- Oral and Intranasal antihistamines
- Intranasal anticholinergics
- Leukotriene receptor antagonists
- As well as immunotherapy and non-medicinal treatment.
- We will dive into them all! But first, let’s talk briefly about allergies as a whole.
Allergic rhinitis (AR) is a disease that is mediated by immunoglobulin-E (IgE) which is believed to occur after exposure to specific allergens, such as molds, dust mites, insects, pollens, or animal dander.
Symptoms of allergic rhinitis may include:
- Nasal obstruction
- And rhinorrhea.
The best treatment of AR includes:
- Avoidance of possible allergens
- Symptomatic control
- When applicable - Immunotherapy.
Allergic Rhinitis Treatment
As discussed above, treatment options for allergic rhinitis include
- Oral and topical antihistamine
- Intranasal corticosteroids
- Intranasal cromolyn
- Intranasal anticholinergics
- And leukotriene receptor antagonists.
The American Academy of Allergy Asthma and Immunology, The International Primary Care Respiratory Group, and The British Society for Allergy and Clinical Immunology all recommend the best first-line treatment option for mild to moderate symptoms is - intranasal corticosteroid as monotherapy.
For moderate to severe allergic rhinitis - add on second-line agents.
Additionally, those patients who have moderate to severe allergic rhinitis that is refractory to oral or topical treatments should be referred to allergy and immunology for evaluation for possible immunotherapy.
Intranasal corticosteroids are the primary option for the treatment of allergic rhinitis. These medications work by decreasing the amount of inflammatory cells and also work to inhibit cytokine release. By working on these two steps, this aims to reduce inflammation of the nasal mucosa.
Once intranasal corticosteroids are used, the onset of effectiveness is around 30 minutes; however, the peak effect can take up to several hours to days, and the maximum effect being noted typically after two to four weeks of continued use.
Efficacy of Intranasal Steroids
Research has revealed that nasal steroids are more effective than oral and intranasal antihistamines in the treatment of allergic rhinitis. One study looked at the quality of life improvements comparing the oral antihistamine - loratadine (Claritin) to the nasal steroid - fluticasone (Flonase). This study found that symptomatic relief scores were similar; however, quality of life scores were significantly higher in the nasal steroid group.
There is no evidence as to which nasal steroid is better. One big thing to note is that a lot of the different nasal steroids have different age indications as to when you can start their use, so always make sure to check this before sending in a prescription or before recommending your patient to get this over the counter.
Safety in Pregnancy/ Medication Delivery
Budesonide (Rhinocort) holds the FDA pregnancy category B safety rating and mometasone (Nasonex) has the only delivery device that has received approval from the National Arthritis Foundation for ease of use.
Adverse effects of intranasal steroids include:
- Throat irritation
- Nose bleeds
- Nasal burning
- Nasal dryness. There has not been any data that states that intranasal steroids cause suppression of the hypothalamic-pituitary axis. Additionally, studies have found no effect on skeletal growth in patients using Mometasone; however, one study revealed children six to nine years of age treated with beclomethasone had suppressed growth rates. Fluticasone has been shown to decrease cortisol excretion; however, the impact on growth is unknown.
Due to some of the conflicting data, all intranasal steroids have a warning on them that long-term use might cause growth restriction in children.
Histamine is the most routinely studied mediator in the allergic response. Histamine causes mucus secretion, smooth muscle contraction, sensory nerve stimulation, and vascular permeability which all leads to symptoms of allergic rhinitis.
First-generation antihistamines include medications such as:
- Clemastine. This class of medication can lead to significant adverse effects. These include fatigue, sedation, or impaired mental status.
These side effects more commonly will occur with first-generation antihistamines due to them being more lipid soluble and are more likely to cross the blood-brain barrier as compared to second-generation antihistamines.
The use of first-generation antihistamines have shown an increase in impaired driving, poor school performance, and an increase in automobile accidents and work injuries.
Compared to first-generation antihistamines, second-generation medications have fewer side effects and cause less sedation.
These medications include:
- Desloratadine (Clarinex)
- Fexofenadine (Allegra)
- Loratadine (Claritin)
- Cetirizine (Zyrtec)
- Levocetirizine (Xyzal).
The more complex structures of second-generation antihistamines decrease their ability to cross the blood-brain barrier. As a group, second-generation antihistamines are thought to treat nasal and ocular symptoms but do not have as much effect on nasal congestion.
Oral Antihistamine Efficacy
In general, both first and second-generation antihistamines have been shown to reduce sneezing, itching, rhinorrhea, and ocular symptoms, but they are less effective than intranasal steroids at treating nasal congestion. Due to their onset being 15 to 30 minutes and their safety for use in patients 6 months and older, these medications are often used in those patients with mild symptoms as an “as needed” or add-on medication.
When comparing intranasal versus oral antihistamines, the intranasal antihistamines provide a higher concentration of medication to the nasal region, therefore, having less adverse effects. Current intranasal antihistamines FDA approved are azelastine and olopatadine.
The onset with these medications is around 15 minutes and lasts up to four hours.
Adverse effects include
- Nasal irritation
- Bitter aftertaste
- Nose bleeds.
Intranasal antihistamines are considered a second-line for those patients whose symptoms do not improve with first-line therapy. This is due mainly to the side effects, as well as the decreased effectiveness in comparison to intranasal corticosteroids.
Oral and topical decongestants aim to help improve nasal congestion symptoms associated with allergic rhinitis. These work by acting on the adrenergic receptors, which lead to vasoconstriction at the site of the nasal mucosa. Common decongestants include oxymetazoline, phenylephrine, and pseudoephedrine.
Common side effects with these medications include sneezing and nasal dryness with intranasal versions. Use of these medications is typically not recommended for longer than three to five days due to causing rhinitis medicamentosa (having rebound or recurring nasal congestions).
Oral decongestants can cause elevated blood pressure, headaches, urinary retention, tremor, dizziness, tachycardia, and insomnia. Close monitoring should take place with patients using these medications.
This medication is available over the counter and is believed to work by inhibiting degranulation of mast cells. This medication is not recommended as a first-line treatment due to its decreased effectiveness in comparison to antihistamines and intranasal steroids. Additionally, its dosing schedule is unfavorable, needing to be used three to four times daily.
Ipratropium (Atrovent) provides benefit to only excessive rhinorrhea. This medication does not cross the blood-brain barrier and is not absorbed into the systemic circulation.
Adverse effects include nose bleeds, dryness of the nasal mucosa, and headache. Compliance can be difficult with this medication as well because it needs to be administered two or three times daily.
Leukotriene Receptor Antagonist
The leukotriene receptor antagonist (LTRA) montelukast (Singulair) has been approved in the treatment of allergic rhinitis; however, data has only shown minimal improvement in symptoms of nasal congestion. Another study found that there was no difference in the symptoms between those patients treated with montelukast and those treated with pseudoephedrine. Although research has shown that LTRA are more effective than placebo, they are not as effective as antihistamines or intranasal steroids, and therefore, should be used as second or third-line treatment options.
Patients who have moderate to severe allergic rhinitis symptoms that are persistent with conventional therapies should be considered for immunotherapy.
This is the only treatment that changes the natural course of the disease and prevents exacerbations of symptoms. Treatment includes a small amount of the patient’s allergens extract given subcutaneously over a span of a few years, with a maintenance timeframe over three to five years.
The greatest risk of immunotherapy is anaphylaxis. The use of sublingual immunotherapy in adults with AR has been supported in studies; however, studies in children have mixed results. The FDA has not approved sublingual use of immunotherapy at this time.
Recombinant DNA technology has played a role in immunotherapy as well. The advancement aims to provide allergen-specific vaccinations. In trials, patients have noted significant improvement in symptoms, skin sensitivity, and the need for medications when compared to placebo.
Lastly, omalizumab (Xolair) is an anti-immunoglobin E antibody that has been seen to be effective in the reduction of nasal symptoms with improvement in the quality of life scores. However, this medication is very expensive, and there is no FDA approval for at home use of the medication.
Acupuncture is believed to play a potential role in the treatment of allergic rhinitis by releasing neurochemicals that reduce inflammatory pathways. Probiotics and herbal preparations have been studied, but have failed to show improvement in allergic rhinitis symptoms.
Patients with allergic rhinitis should avoid exposure to pet dander, smoke, and allergens that they are known to have a sensitivity to. Nasal irrigation should be recommended with a Neti pot or low-pressure squeeze bottles.
- Am Fam Physician. Treatment of Allergic Rhinitis. 2010;81(12):1440-1446. Copyright © 2010 American Academy of Family Physicians.
- UpToDate. Pharmacotherapy of Allergic Rhinitis. Accessed: April 8, 2019.
- UpToDate. Pathogenesis of Allergic Rhinitis. Accessed: April 8, 2019.