Unlike autumn or spring allergies, which are often responses to outdoor allergens like pollen, most winter allergies are triggered by substances inside the home.

Winter carries several risk factors for an exacerbation in respiratory allergies.

Winter allergies result in the same symptoms patients experience throughout the rest of the year. According to Charleston Allergy and Asthma Consultants, patients often experience nasal congestion or stuffy nose, runny nose, itchy nose, sinus pressure, sneezing, postnasal drainage down the back of their throats, and itchy or watery eyes.  

COMMON CAUSES 

  • Dust mites: Found in bedding, furniture, and carpets, rhinitis is not caused by the dust mites themselves, but by a chemical found in their excrement. Although they are present all year round, dust mites’ numbers tend to peak during winter. 
  • Mould: We all breathe in mould spores, but for those with an allergy, exposure can trigger sneezing, congestion, and itchiness. Found in dark moist areas like bathrooms, basements, and under sinks, airborne moulds are well-known causes of allergic rhinitis and asthma.  
  • Pet dander: Dogs and cats are the most common animals to cause allergies. Found on almost any indoor surface (beds, carpets, furniture, etc.), the allergic reaction is not caused by animal fur, but flakes of dead animal skin, urine, and saliva.  
  • Cockroach droppings: Found in moist areas, especially kitchen cupboards, under sinks, or behind appliances, these pests can live anywhere. Inhalation of cockroach droppings can worsen allergic rhinitis and asthma. 

While these indoor allergens are present year-round, allergies can flare up in the winter because patients are cooped up in the house with the windows closed.  

WORSENING OF WINTER ALLERGIES 

  • WINTER VIRUSES: Cold and flu viruses, which are prolific during winter, can mimic allergic symptoms and simultaneously exacerbate rhinitis and chest symptoms, explained Prof Claudia Gray (allergologist and paediatrician) on behalf of the Allergy Foundation SA. “Pre-existing allergies can, in turn, also lead to prolongation of cold and flu symptoms. Frequent use of nasal saline rinses and diligent use of allergic rhinitis and asthma control treatment such as intranasal/inhaled corticosteroids can lessen the impact of viral illnesses.” 
  • COLD AIR: “Cold-induced airway irritation or damage can cause rhinorrhoea or bronchospasm,” said Prof Gray. “This is worsened by rapid decreases in temperature and is particularly manifest during exercise in cold weather when the normal compensatory nasal humidification is bypassed during exercise-induced hyperventilation.” 
  • OTHER FACTORS: Further factors such as an increase in the use of indoor fires, higher pollution production, increased use of air-drying indoor heaters can all worsen respiratory allergies. 

TREATMENT 

There are fortunately many options for the treatment of allergic rhinitis. Dermatologist Dr Karen Koch advised to always check which treatments your patient has previously used or is currently using before recommending an additional measure.  

NASAL IRRIGATION AND SALINE SPRAYS  

Nasal irrigation or nasal lavage with a salt-water (saline) solution can be very effectiveSaline is also available in a standard nasal spray, although this is not as effective as using larger amounts of water in an irrigation,” said Dr Koch. “Nasal irrigation is particularly useful for treating drainage down the back of the throat, sneezing, nasal dryness, and congestion. The treatment helps by rinsing out allergens and irritants from the nose. Saline rinses also clean the nasal lining and can be used before applying sprays containing medications, to get a better effect from the medication.  

“You can recommend your patient tries nasal irrigation once or twice per day using sterilised water and salt. Saline nasal sprays and irrigation kits can be purchased over the counter (OTC) and include a variety of devices, such as bulb syringes and bottle sprayers. At least 200ml of fluid (salt solution made with distilled or boiled water or sterile saline, not tap water) is recommended for each nostril.”  

NASAL GLUCOCORTICOIDS  

Nasal glucocorticoids are the first-line treatment for symptoms of allergic rhinitis. “These drugs have few side effects and dramatically relieve symptoms in most people.” According to Dr Koch, studies have shown that nasal glucocorticoids are more effective than oral antihistamines for symptom relief. “While certain nasal glucocorticoids require a prescription, others are OTC medications you can recommend. Make sure you advise your patient that relief from symptoms may take up to two weeks. For this reason, it’s important that they use their spray daily or twice daily as prescribed.”  

ANTIHISTAMINES  

Antihistamines relieve itching eyes and itching, sneezing, and runny nose caused by winter allergies, but they do not relieve nasal congestion. Combined treatment with nasal steroids or decongestants may provide greater symptom relief than the use of either alone,” advised Dr KochWhen recommending an antihistamine that causes drowsiness, encourage your patient to use them in the evening. Alternately suggest an antihistamine that does not cause drowsiness.  

EYE DROPS 

Allergy eye drops can help with dry, red, or itchy eyes. Because all eye drops are not the same, it’s important to find out what is bothering your patient most and select a product that is best for their symptoms.  

DECONGESTANTS  

Designed for controlling symptoms of colds or flu, decongestants should not be used on an ongoing basis to control allergy symptomsYou can recommend them for a few days while a patient starts nasal glucocorticoids or antihistamines. Used for more than one or two weeks at a time, they can cause rebound sinusitis,” cautioned Dr Koch.  

ALLERGY SHOTS  

For patients who have positive allergy testing and do not achieve enough relief with OTC or prescription nasal sprays, oral antihistamines, and eye drops, allergy immunotherapy is often recommended. A course of histaglobin injections can help to significantly reduce allergies in adults, However, injections are expensive and reserved only for those not controlled on standard treatment.”  

LEUKOTRIENE MODIFIERS  

The prescription medication montelukast is used to treat asthma but also helps with symptoms of allergic rhinitis. If your patient doesn’t have asthma these drugs are usually only used where nasal glucocorticoids are not effective.  

If a patient’s allergy symptoms don’t get better with treatment, last for a few weeks or more, or interrupt their daily lifestyle, encourage them to see an allergologist.  

“Winter carries several risk factors for an exacerbation in respiratory allergies. Patients and healthcare providers should ensure that allergic rhinitis and asthma medication plans are up to date and being adhered to, and that indoor allergen exposure is reduced as much as possible during wintertime,” concluded Prof Gray.