It’s spring in the northern hemisphere, and for millions, it’s a miserable time. Sneezing, nasal congestion and itchy eyes – and it’s probably not something infectious, but more likely the symptoms of allergic rhinitis (sometimes called seasonal allergies). Allergic rhinitis can impair quality of life, work productivity, and even sleep. Stemming from a recent request, I wanted to catch up on allergic rhinitis, discuss environmental triggers, and review the range of treatment options, both drug and non-drug.
Prevalence and Mechanism
Allergic rhinitis is triggered when the immune system reacts to otherwise harmless airborne substances, such as pollen, dust mites, mold spores, or pet dander. Allergic rhinitis affects both children and adults, with global prevalence estimates ranging from 25% to 40% depending on the region and age group. The prevalence is increasing, which is attributed in part to climate change causing longer pollen seasons and higher pollen counts.
Beyond discomfort, allergic rhinitis imposes a significant burden through reduced quality of life, increased absenteeism from work or school, and increased healthcare costs. It also frequently coexists with or can can worsen other respiratory conditions, such as asthma.
Allergic rhinitis is a “Type I” hypersensitivity reaction, mediated by immunoglobulin E (IgE). Upon initial exposure to an allergen, the immune system becomes sensitized, producing allergen-specific IgE antibodies that bind to mast cells in the mucus membranes in the nose. Subsequent exposures cause these sensitized mast cells to rupture, releasing histamine, leukotrienes, and other proinflammatory mediators. This causes the classic allergic symptoms—nasal congestion, sneezing, runny nose and itchy skin – often within minutes. A later phase, driven by eosinophils, can cause the inflammation to last for for hours or days.
Causes, Triggers and Risk Factors
Allergic rhinitis is typically triggered by airborne environmental allergens. Seasonal allergens include pollens from grasses, trees, and weeds, while year-round (perennial) triggers tend to be from indoor exposures to substances such as dust mites, mould spores, pet dander, and (shudder) cockroach droppings. Genetics plays a substantial role: Individuals with a family history of atopic disease (such as asthma, eczema, or allergic rhinitis) are significantly more likely to develop allergic rhinitis. Living conditions, tobacco smoke exposure, and early-life microbial exposures (e.g., farm living) may also influence susceptibility.
Diagnosing Allergic Rhinitis
Assessing allergic rhinitis ideally involves a clinician who will perform a physical examination, evaluate symptoms, and document their history. It usually presents with sneezing, runny noses, nasal congestion and nasal itching. Eye itching, tearing and pain may also be present as well, and is called allergic conjunctivitis. Symptom timing, duration, and association with triggers should be identified. Allergic shiners (dark discolouration under the lower eyelids) is a common sign. A physician will typically try to understand symptoms, triggers, seasonal effects, environmental effects, and family history. Allergic rhinitis is usually suggested if triggers are identified. When symptoms are severe, usual treatments fails, or the diagnosis remains unclear, allergy testing (usually skin prick tests) can be helpful.
Non-Drug Strategies
Non-drug strategies are central to allergic rhinitis management, especially in mild cases. Start with following local pollen forecasts, if pollen is a cause. Allergen avoidance is ideal in theory, but not always feasible. You cannot eliminate pollen or even dust mites from your life, but you can reduce exposure with masking, air filters (home and car), and mite-proof bedding covers. Nasal saline irrigation with low volume liquids (e.g., saline nasal sprays) or large volume liquids (e.g., neti pots) have been shown to be effective, reducing symptom severity. They are also safe, as long as distilled/previously boiled or otherwise sterilized water is used. Artificial tears and cooling eye compresses may provide some relief to itchy eyes. Finally, allergen immunotherapy, either subcutaneous (SCIT) or sublingual (SLIT) is the only disease-modifying option, which can reduce the long-term symptom burden and medication use through gradual desensitization.
Drug-based Strategies
There are dozens, probably hundreds of products to treat allergies on pharmacy shelves, and some treatment options require a prescription. The choice of product is usually guided by severity of symptoms, their frequency, and patient preferences. What follows is a high level summary of the major treatment options for adults – this is not individual advice. For brevity, it doesn’t address factors like other medications, medical conditions, or circumstances like pediatric uses, pregnancy or lactation. A qualified health professional should be consulted who can provide recommendations that consider patient factors and preferences. Just because many medications to treat allergies do not require a prescription does not mean that these products are free of side effects, or can be combined with other medications safely.
Intranasal steroids – The “second generation” drugs like ciclesonide, fluticasone, or mometasone are preferred treatments and are very effective for moderate to severe allergies. These steroids may offer an advantage over “first generation” products (e.g., beclomethasone, budesonide, flunisolide and triamcinolone) in that very little of the drug is ultimately absorbed into the bloodstream and available to the rest of the body (where steroids can have negative, unwanted effects). Steroid nasal spray typically require a prescription, but that will vary by products and country. To prevent allergies, they need to be started 1-2 days before anticipated exposure. Effectiveness may take days to weeks to evaluate. Technique for administration matters, and it can vary by product – ask your pharmacist. For persistent allergies, intranasal steroids may need to be used regularly. Often when symptoms are controlled, doses can be reduced – sometimes to every-other-day or just when needed. Intranasal steroids are felt to be superior to antihistamines, particularly for treating nasal congestion.
Antihistamine nasal sprays – These products contain ingredients like azelastine or olopatadine. They are effective for those that do not want steroid sprays, and have the advantage of being effective if used immediately before allergen exposure, taking effect in about 15 minutes.
Antihistamines are also found in combination steroid-antihistamine sprays which have the benefit of acting rapidly and in a complementary way to provide additional benefit when single products are not effective.
Oral antihistamines – “Second generation” antihistamines such as cetirizine, fexofenadine or loratidine are popular owing to their non-prescription status and long history of use. Oral antihistamines effectively reduce itching, sneezing, and runny nose, as well as eye itchiness, but are less effective for nasal congestion compared with steroid sprays. They are less sedating and just as effective as the older “first-generation” antihistamines. These older antihistamines, such as chlorpheniramine or diphenhydramine have been used for decades and continue to be used despite the availability of much safer and tolerable “second generation” products. Contrary to marketing, no antihistamine has been shown to be demonstrably better for a specific allergen than another. If one antihistamine does not work however, another may be effective and switching may be necessary to find a product that work.
Decongestants – In the USA you can’t easily access pseudoephedrine (the OG and most effective oral decongestant) but topical sprays that contain ingredients like oxymetazoline are effective and can provide quick relief. However, a problem with decongestant sprays is that they can cause rebound congestion if used regularly for more than a few days. Phenylephrine is marketed as a decongestant and may still be found in products – its efficacy is indistinguishable from placebo. Depending on where you live, decongestants may be combined with antihistamines, but are not preferred products unless it’s been shown that combined use provides relief over antihistamines or decongestants alone.
Alternatives to Conventional Medicines
There are highly effective non-drug and drug-based therapies for allergic rhinitis. Evidence for other alternatives (“natural” or otherwise) is limited. Local/raw raw honey has been promoted as “natural immunotherapy” yet the evidence is not consistent or impressive. Acupuncture has been promoted, yet there is adequate evidence presented and discussed at this blog to show that acupuncture’s effects seem to placebo effects. There are interest in herbal remedies and some have been studied in clinical trials, but there are concerns about the quality of evidence, and overarching concerns about the standardization and manufacturing consistency of these products. Overall, given the effectiveness of non-drug therapies like saline sprays and rinses, it’s possible to address some cases of allergic rhinitis without medication (or alternative medicines) at all.
Practical, Individual Approaches
Allergic rhinitis may be considered a “minor” ailment but it can have extensive and prolonged negative effects on ones quality of life. A combination of avoidance, exposure minimization, and an evidence-based use of drug and non-drug measures can bring symptoms under control for many. While self-treatment may be effective, the assessment and advice of health professionals can be valuable in identifying causes and finding the right treatments. Ultimately, the most successful approach will always be a personalized one—tailored to individual triggers, preferences, and lifestyle, and utilizing evidence and available approaches to find what works.