Cat allergies refer to an overreaction of the immune system to proteins found in cat dander, saliva or urine. Asthma is a chronic lung disease characterized by inflammation and narrowing of the airways, leading to wheezing, coughing, chest tightness and shortness of breath.
Cat allergies are very common, affecting 10-20% of the general population worldwide (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8721548/). Asthma is also a prevalent condition, with estimates that it affects around 8% of the US population.
There is considerable overlap between cat allergies and asthma – over 60% of people with asthma also have allergies. Exposure to cat allergens can trigger asthma symptoms or exacerbations in those with allergic asthma. Managing both conditions requires avoiding asthma triggers like cat dander while controlling underlying inflammation.
Relationship Between Cat Allergies and Asthma
Numerous studies have found evidence linking cat allergies to an increased risk of developing asthma symptoms and attacks. According to a 2012 review in PMC, exposure to cat allergens, especially in early childhood, can predispose people to sensitization and allergic reactions later in life. The review cited research showing children with cat allergies were 3-4 times more likely to develop asthma compared to those without cat allergies.
The mechanism behind this relationship may involve an overactive immune response. Cats produce allergenic proteins in their saliva, skin cells, and urine. When inhaled by someone with cat allergies, these proteins can trigger an IgE-mediated reaction, causing immune cells to release inflammatory chemicals like histamine. This inflammation in the airways is thought to make asthmatic patients more prone to bronchoconstriction and asthma exacerbations when exposed to cat allergens.
Symptoms
Exposure to cats can trigger symptoms of both allergies and asthma. Common allergy symptoms include sneezing, runny nose, watery eyes, and itchy skin, eyes, nose or roof of mouth, as noted by Healthline (https://www.healthline.com/health/asthma/cats-and-asthma). Allergy symptoms often begin shortly after exposure to cats and may continue for hours or days afterward. Asthma symptoms can also be triggered by cat allergens and tend to affect the respiratory system. These include coughing, wheezing, shortness of breath, and chest tightness, according to Medical News Today (https://www.medicalnewstoday.com/articles/cats-and-asthma). Asthma flare-ups from cat allergens can range from mild to severe. In some cases, a cat-induced asthma attack requires immediate medical treatment.
Diagnosis
To diagnose cat allergy-induced asthma, doctors will typically use a combination of allergy testing and lung function tests.1
Common allergy tests include:
- Skin prick test – Drops containing cat allergens are placed on the skin, which is then pricked with a needle. If a red, itchy bump forms, it indicates an allergy.
- Blood test – A blood sample is analyzed for antibodies to cat dander and saliva.
- Patch test – Patches containing cat allergens are placed on the skin for 48 hours. If a reaction occurs, it confirms an allergy.
To evaluate lung function, doctors may use tests like:
- Spirometry – Measures how much air can be inhaled and exhaled, and how fast.
- Peak flow meter – Measures maximum speed of expiration.
- Methacholine challenge – Increasing amounts of methacholine are inhaled to see if it narrows airways.
These lung function tests help diagnose asthma and assess its severity in those with suspected cat allergy-triggered asthma.
Treatment
There are several treatment options for managing cat allergy-induced asthma symptoms. The main treatments include allergy medications like antihistamines and steroids as well as asthma inhalers and medications.
Antihistamines such as cetirizine (Zyrtec) or loratadine (Claritin) can help relieve allergy symptoms like sneezing, itchy eyes, and runny nose. These medications block the effects of histamine, which the body releases in response to an allergen. Antihistamines are available over-the-counter or by prescription. While antihistamines treat allergy symptoms, they do not treat the underlying inflammation associated with asthma.
Nasal steroid sprays such as fluticasone (Flonase) are more effective at reducing inflammation caused by a cat allergy. Steroids work by reducing swelling and mucus production. Often a combination of an antihistamine and nasal steroid spray is recommended. Oral steroids may also be prescribed for short periods to treat severe allergy symptoms.
For asthma symptoms like coughing, wheezing, and shortness of breath, asthma inhalers and medications are used to open airways and reduce inflammation. Inhaled corticosteroids are commonly prescribed to prevent asthma attacks. Bronchodilators like albuterol provide quick relief by relaxing airway muscles. Long-term medications may be needed to control allergy-induced asthma.
By treating both the allergy and asthma components, medications can help reduce asthma flare-ups caused by exposure to cats. However, avoiding or limiting contact with cats remains an important part of managing this type of asthma.
Allergy Shots
Allergy shots, also known as allergen immunotherapy, are a form of treatment that involves being injected with small amounts of the allergen over time. The goal is to reduce the immune system’s reaction to the allergen. Allergy shots work by helping the body build immunity or tolerance to the allergen.
Research shows allergy shots can be an effective treatment for cat allergies and asthma. According to the National Institutes of Health, allergy shots for cat allergens provided longer-lasting relief of symptoms compared to placebo injections in a clinical trial of people with cat allergies [1]. Another NIH study found that adding a monoclonal antibody to cat allergen immunotherapy significantly improved outcomes [2]. And a recent study in Healio showed a single dose of immunotherapy for cat allergies prevented reductions in lung function in people with mild asthma [3].
Avoidance
One of the most effective ways to manage cat allergies and asthma is to avoid exposure to cat allergens as much as possible. For some, this may mean removing cats from the home. While difficult, this step can significantly reduce allergy and asthma symptoms. Consider rehoming the cat with a trusted friend or family member or contacting a no-kill shelter. Thoroughly clean the home with HEPA vacuuming and deep cleaning of carpets, furniture, and other surfaces the cat touched. This will help remove dander and minimize leftover allergens. Medical News Today
If removing the cat is not an option, take steps to reduce allergens at home. Keep cats out of bedrooms and limit them to one area of the home. Use HEPA air purifiers and vacuum frequently with a HEPA filter. Wash bedding on hot water weekly. Consider replacing carpets with hard flooring, and use upholstery that doesn’t accumulate allergens easily. Wipe down surfaces regularly. Bathing cats weekly may help, but is often not enough for those with severe allergies. Work closely with an allergist to find optimal ways to reduce allergens at home. With diligence, those with cat allergies can find relief through avoidance and allergen reduction techniques.
Other Allergy Control Measures
In addition to allergy medication and avoidance, there are other ways to help control allergies to cats:
Air filters can be effective at removing allergens from the air. High efficiency particulate air (HEPA) filters are recommended for allergy sufferers. Portable room air cleaners with HEPA filters can filter out dander and other allergens. Filters should be changed regularly according to manufacturer recommendations.
Frequent cleaning is also important. Cat allergens can stick to surfaces like furniture and carpets. Vacuuming with a HEPA filter vacuum weekly can help remove allergens. Washing bedding and soft furnishings regularly in hot water is also recommended. Hard surfaces like floors and countertops should be wiped down frequently.
Managing Asthma
If you have asthma triggered by cat allergies, it’s important to follow an asthma action plan and avoid asthma triggers to help control your symptoms. An asthma action plan outlines the medications you should take on a daily basis as well as rescue medications for when symptoms flare up. The plan is created with your doctor and tailored to your specific triggers and symptom history. Following the action plan closely and taking medications as prescribed can help prevent asthma attacks.
You should also try to avoid asthma triggers as much as possible. For cat allergies, this may mean keeping cats out of your bedroom at all times, using air purifiers and vacuums with HEPA filters, washing hands after touching cats, and taking medication before interactions with cats. Other common asthma triggers to avoid include tobacco smoke, pollen, mold, cold air, respiratory infections, exercise, and stress. Keeping an asthma diary can help you identify your personal asthma triggers.
While cat allergies can be difficult to manage with asthma, following an asthma action plan, avoiding triggers, and working closely with your doctor can help control symptoms and allow you to breathe easier.
Outlook
Although cat allergies can worsen asthma symptoms, long term control is possible through proper treatment and management[1]. Consulting an allergist is crucial, as they can help patients understand their sensitivities and prescribe allergy shots tailored to their specific allergens[2]. With allergy shots and avoidance of triggers, people with cat allergies can successfully control their asthma. An allergist may also recommend additional allergy medications like antihistamines and nasal sprays for controlling allergy symptoms day-to-day.
While complete allergy relief may not be realistic, significant improvements are possible. With proactive treatment from an allergist, testing, environmental controls, and lifestyle adjustments, those with asthma aggravated by cat allergies can achieve an improved quality of life.
[1] https://www.nature.com/articles/d41586-020-02775-7
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3707607/