What is the best over the counter medicine for pollen allergies

The symptoms of allergic rhinitis may at first feel love those of a freezing. But unlike a freezing that may incubate before causing discomfort, symptoms of allergies generally appear almost as soon as a person encounters an allergen, such as pollen or mold.

Symptoms include itchy eyes, ears, nose or throat, sneezing, irritability, nasal congestion and hoarseness. People may also experience cough, postnasal drip, sinus pressure or headaches, decreased sense of smell, snoring, sleep apnea, fatigue and asthma, Josephson said. [Oral Allergy Syndrome: 6 Ways to Avoid an Itchy, Tingling Mouth]

Many of these symptoms are the immune system’s overreaction as it attempts to protect the vital and sensitive respiratory system from exterior invaders.

The antibodies produced by the body hold the foreign invaders out, but also cause the symptoms characteristic of allergic responses.

People can develop hay fever at any age, but most people are diagnosed with the disorder in childhood or early adulthood, according to the Mayo Clinic. Symptoms typically become less severe as people age.

Often, children may first experience food allergies and eczema, or itchy skin, before developing hay fever, Josephson said. «This then worsens over the years, and patients then develop allergies to indoor allergens love dust and animals, or seasonal rhinitis, love ragweed, grass pollen, molds and tree pollen.»

Hay fever can also lead to other medical conditions.

People who are allergic to weeds are more likely to get other allergies and develop asthma as they age, Josephson said. But those who get immunotherapy, such as allergy shots that assist people’s bodies get used to allergens, are less likely to develop asthma, he said.


Tests & diagnosis

A physician will consider patient history and act out a thorough physical examination if a person reports having hay-fever-like symptoms. If necessary, the physician will do an allergy test. According to the Mayo Clinic, people can get a skin-prick test, in which doctors prick the skin on a person’s arm or upper back with diverse substances to see if any cause an allergic reaction, such as a raised bump called a hive.

[7 Strange Signs You’re Having an Allergic Reaction]

Blood tests for allergies are also available. This test rates the immune system’s response to a specific allergen by measuring the quantity of allergy-causing antibodies in the bloodstream, according to the Mayo Clinic.


Signs and symptoms

Affected organ Common signs and symptoms
Nose Swelling of the nasal mucosa (allergic rhinitis) runny nose, sneezing
Sinuses Allergic sinusitis
Eyes Redness and itching of the conjunctiva (allergic conjunctivitis, watery)
Airways Sneezing, coughing, bronchoconstriction, wheezing and dyspnea, sometimes outright attacks of asthma, in severe cases the airway constricts due to swelling known as laryngeal edema
Ears Feeling of fullness, possibly pain, and impaired hearing due to the lack of eustachian tube drainage.

Skin Rashes, such as eczema and hives (urticaria)
Gastrointestinal tract Abdominal pain, bloating, vomiting, diarrhea

Many allergens such as dust or pollen are airborne particles. In these cases, symptoms arise in areas in contact with air, such as eyes, nose, and lungs. For instance, allergic rhinitis, also known as hay fever, causes irritation of the nose, sneezing, itching, and redness of the eyes.[21] Inhaled allergens can also lead to increased production of mucus in the lungs, shortness of breath, coughing, and wheezing.[22]

Aside from these ambient allergens, allergic reactions can result from foods, insect stings, and reactions to medications love aspirin and antibiotics such as penicillin.

What is the best over the counter medicine for pollen allergies

Symptoms of food allergy include abdominal pain, bloating, vomiting, diarrhea, itchy skin, and swelling of the skin during hives. Food allergies rarely cause respiratory (asthmatic) reactions, or rhinitis.[23] Insect stings, food, antibiotics, and certain medicines may produce a systemic allergic response that is also called anaphylaxis; multiple organ systems can be affected, including the digestive system, the respiratory system, and the circulatory system.[24][25][26] Depending on the rate of severity, anaphylaxis can include skin reactions, bronchoconstriction, swelling, low blood pressure, coma, and death.

This type of reaction can be triggered suddenly, or the onset can be delayed. The nature of anaphylaxis is such that the reaction can seem to be subsiding, but may recur throughout a period of time.[26]

Skin

Substances that come into contact with the skin, such as latex, are also common causes of allergic reactions, known as contact dermatitis or eczema.[27] Skin allergies frequently cause rashes, or swelling and inflammation within the skin, in what is known as a «weal and flare» reaction characteristic of hives and angioedema.[28]

With insect stings a large local reaction may happen (an area of skin redness greater than 10 cm in size).[29] It can final one to two days.[29] This reaction may also happen after immunotherapy.[30]


Hay fever treatments

Dr.

Sarita Patil, an allergist with Massachusetts General Hospital’s Allergy Associates in Boston, talked to Live Science about strategies for outdoor lovers with seasonal allergies.

Patil suggested figuring out exactly what type of pollen you’re allergic to, and then avoiding planning outdoor activities during peak pollinating times in the months when those plants are in bloom. Numerous grasses, for example, typically pollinate in tardy spring and early summer and release most of their spores in the afternoon and early evening.

Her other strategies: Be capable to identify the pollen perpetrator by sight; monitor pollen counts before scheduling outdoor time; go exterior at a time of day when the plants that make you go achoo are not pollinating; and wear protective gear love sunglasses, among other tips.

[7 Strategies for Outdoor Lovers with Seasonal Allergies]

Allergy sufferers may also select to combat symptoms with medication designed to shut below or trick the immune sensitivity in the body. Whether over-the-counter or prescription, most allergy pills work by releasing chemicals into the body that bind naturally to histamine — the protein that reacts to the allergen and causes an immune response — negating the protein’s effect.

Other allergy remedies attack the symptoms at the source. Nasal sprays contain athletic ingredients that decongest by soothing irritated blood vessels in the nose, while eye drops both moisturize and reduce inflammation. Doctors may also prescribe allergy shots, Josephson said.

For kids, allergy medications are tricky.

A 2017 nationally representative poll of parents with kids between ages 6 and 12 found that 21% of parents said they had trouble figuring out the correct dose of allergy meds for their child; 15% of parents gave a kid an adult form of the allergy medicine, and 33% of these parents also gave their kid the adult dose of that medicine.

Doctors may also recommend allergy shots, a neti pot that can rinse the sinuses, or a Grossan Hydropulse — an irrigating system that cleans the nose of pollens, infection and environmental irritants, Josephson said.

Alternative and holistic options, along with acupuncture, may also assist people with hay fever, Josephson said.

People can also avoid pollen by keeping their windows closed in the spring, and by using air purifiers and air conditioners at home.

Probiotics may also be helpful in stopping those itchy eyes and runny noses. A 2015 review published in the journal International Forum of Allergy and Rhinology found that people who suffer from hay fever may benefit from using probiotics, or «good bacteria,» thought to promote a healthy gut. Although the jury is still out on whether probiotics are an effective treatment for seasonal allergies, the researchers noted that these gut bacteria could hold the body’s immune system from flaring up in response to allergens — something that could reduce allergy symptoms.

[5 Myths About Probiotics]

Additional resources:

This article was updated on April 30, 2019, by Live Science Contributor Rachel Ross.

Hay fever treatments

Dr. Sarita Patil, an allergist with Massachusetts General Hospital’s Allergy Associates in Boston, talked to Live Science about strategies for outdoor lovers with seasonal allergies.

Patil suggested figuring out exactly what type of pollen you’re allergic to, and then avoiding planning outdoor activities during peak pollinating times in the months when those plants are in bloom.

Numerous grasses, for example, typically pollinate in tardy spring and early summer and release most of their spores in the afternoon and early evening.

Her other strategies: Be capable to identify the pollen perpetrator by sight; monitor pollen counts before scheduling outdoor time; go exterior at a time of day when the plants that make you go achoo are not pollinating; and wear protective gear love sunglasses, among other tips. [7 Strategies for Outdoor Lovers with Seasonal Allergies]

Allergy sufferers may also select to combat symptoms with medication designed to shut below or trick the immune sensitivity in the body.

Whether over-the-counter or prescription, most allergy pills work by releasing chemicals into the body that bind naturally to histamine — the protein that reacts to the allergen and causes an immune response — negating the protein’s effect.

Other allergy remedies attack the symptoms at the source.

What is the best over the counter medicine for pollen allergies

Nasal sprays contain athletic ingredients that decongest by soothing irritated blood vessels in the nose, while eye drops both moisturize and reduce inflammation. Doctors may also prescribe allergy shots, Josephson said.

For kids, allergy medications are tricky. A 2017 nationally representative poll of parents with kids between ages 6 and 12 found that 21% of parents said they had trouble figuring out the correct dose of allergy meds for their child; 15% of parents gave a kid an adult form of the allergy medicine, and 33% of these parents also gave their kid the adult dose of that medicine.

Doctors may also recommend allergy shots, a neti pot that can rinse the sinuses, or a Grossan Hydropulse — an irrigating system that cleans the nose of pollens, infection and environmental irritants, Josephson said.

Alternative and holistic options, along with acupuncture, may also assist people with hay fever, Josephson said.

People can also avoid pollen by keeping their windows closed in the spring, and by using air purifiers and air conditioners at home.

Probiotics may also be helpful in stopping those itchy eyes and runny noses. A 2015 review published in the journal International Forum of Allergy and Rhinology found that people who suffer from hay fever may benefit from using probiotics, or «good bacteria,» thought to promote a healthy gut. Although the jury is still out on whether probiotics are an effective treatment for seasonal allergies, the researchers noted that these gut bacteria could hold the body’s immune system from flaring up in response to allergens — something that could reduce allergy symptoms.

[5 Myths About Probiotics]

Additional resources:

This article was updated on April 30, 2019, by Live Science Contributor Rachel Ross.

Introduction

According to Australian Institute of Health and Welfare (AIHW) [1], in 2014−15 almost 1 in 5 Australian suffered from Pollen allergy, which amounts to 4.5 mln of citizens, predominantly working-aged adults. What is more, the expenditure on Allergic rhinitis medications doubled between 2001 and 2010, going from $107.8 mln to $226.8 mln per year, as reported by Australian pharmacies [1].

Overall allergies are increasing, but the reasons for an observed growth are not entirely clear [2, 3].

The potential of social media for public health mining has already been demonstrated in previous studies on Adverse Drug Reactions (ADRs) [4–8], antibiotics misuse [9], influenza detection [10–12], allergy surveillance [13–17], and so on. Still, the automatic approaches frequently under-perform when exposed to novel/creative phrases, sarcasm, ambiguity and misspellings [6, 18, 19].

Consequently, the conventional machine learning classifiers struggle with correct identification of non-medical expressions such as ’hay fever sob’ or ’dribbling nose’, typical of social media discourse. On the other hand, the large proportion of user-generated content is of either commercial or informative nature — irrelevant for surveillance and knowledge discovery purposes. The news, warnings, products and services ads related to the condition can be published by both public as well as private accounts, limiting usability of the associated metadata.

A critical challenge lies in abstracting essential information, in the context of Hay fever surveillance, from highly unstructured user-generated content to support public health monitoring from social media.

Deep learning emerged as a sub-field of machine learning and already benefited numerous Natural Language Processing (NLP) tasks [20]. The ability to study the most salient aspects from text automatically eliminated the need for conventional classifiers dependent on manual feature-engineering. Further application of expression embeddings allowed to account for syntactic and semantic regularities between the words, leading to classification performance improvement.

As state-of-the-art approach, deep learning in public health mining domain is still in its infancy. Previous studies on allergies surveillance from social media conducted in the UK and US utilised either traditional machine learning classifiers such as Multinomial Naive Bayes [13, 17], or lexicon-based approaches [14–16]. The application of deep learning for Hay fever-related user-generated content identification and knowledge discovery about the condition in Australia is yet to be explored in the literature.

Deep learning in text classification

Gao et al.

[30] demonstrated how deep learning approach can improve model performance for multiple information extraction tasks from unstructured cancer pathology reports compared to conventional methods. The corpus of 2505 reports was manually annotated for (1) primary site (9 labels), and (2) histological grade (4 labels) identification. The models tested were RNN, CNN, LSTM and GRU, and expression embeddings were implemented for word-to-vector representation.

Another study explored the effectiveness of domain-specific expression embeddings on classification performance in Adverse Drug Reactions (ADRs) extraction from social media [5]. The data was collected from and DailyStrength (the online support community dedicated to health issues), followed by annotation of entire of 7663 posts for presence of (1) adverse reactions, (2) beneficial effects, (3) condition suffered, and (4) other symptoms. The use of expression embeddings enabled even the non-medical expressions correct identification in highly informal social media streams.

The improved performance following the domain-specific embeddings development was also demonstrated in the classification of ADRs-related [12] (medical embeddings), and crisis-related tweets [31] (crisis embeddings). The previous employed the bi-directional LSTM model for detection of ADRs, Drug Entities and others. The latter used CNN model for binary identification of useful versus non-useful posts during a crisis event. Similarly, CNN was successfully applied in personality identification [32], sarcasm detection [33], aspect extraction [34] or emotion recognition [35].

CNNs capture the most salient n-gram information by means of its convolution and max-pooling operations.

In terms of NLP tasks, RNNs are found particularly suitable due to the ability to process variable length inputs as well as long-distance expression relationships [36]. In text classification, the dependencies between the middle and far-away words can be meaningful and contribute towards performance improvement [37]. The LSTMs (Long Short-Term Memory), as variants of RNNs — can leverage both short and long-distance expression relationships [37]. Unlike LSTMs, GRUs (Gated Recurrent Unit) fully expose their memory content each timestep, and whenever a previously detected feature, or the memory content is considered to be significant for later use, the update gate will be closed to carry the current memory content across multiple timesteps [38].

Based on empirical results, GRUs outperformed LSTMs in terms of convergence in CPU time and in terms of parameter updates and generalisation by using fixed number of parameters for every models on selected datasets [39].

Allergies surveillance from social media

Given the limitations of traditional approaches for allergies surveillance, the alternative sources of data increase in importance to closer reflect the state of the condition within the population. One domain that has grown by massive proportions in recent years, as well as continues to grow, is social media [6, 26].

Online platforms attract and urge users to discuss their health issues, use of drugs, side effects and alternative treatments [6]. The updates range from generic signs of dissatisfaction (e.g. ’hay fever sucks’) to specific symptoms description (e.g. ’my head is killing me’). Also, it has been observed that individuals often prefer to share their health-related experiences with peers, rather than during clinical studies, or even physicians [27]. As a result, social media has become a source of valuable data, increasingly used for real-time detection and knowledge discovery [28].

Previous studies conducted in UK and US own already investigated the potential of for allergies surveillance.

De Quincey et al. [15] observed that users are self-reporting the symptoms as well as medications, and the volume of Hay fever-related tweets strongly correlates (r=0.97, p<0.01) with incidents of Hay fever reported by Royal College of General Practitioners (RCGP) within the same year in the UK. Another correlation has been found in the work published by Cowie et al. [17], where the volume of Pollen allergy-related tweets collected in the UK over the period of 1 year resembled the pattern of pollen counts — grass pollen in specific.

What is the best over the counter medicine for pollen allergies

The study performed in the US has reported similar findings — strong correlations between (1) pollen rates and tweets reporting Hay fever symptoms (r=0.95), and (2) pollen rates and tweets reporting the use of antihistamines (r=0.93) [16]. Lee et al. [13] further observed the relationship between the weather conditions (daily maximum temperature), and number of conversations about allergies on . Additionally, the classification of actual allergy incidents and general awareness promotion was employed, along with the specific allergy types extraction.

The correlations between the environmental factors and Hay fever-related tweets were also performed in the small-scale Australian study [29], where moderately strong dependencies were found for Temperature, Evaporation and Wind — every crucial factors in allergies development.

Prevalence and severity of Hay fever

Pollen allergy, commonly known as Hay Fever, significantly reduces the quality of life and affects physical, psychological and social functioning.

The symptoms experienced are caused by body’s immune response to the inhaled pollen, resulting in chronic inflammation of eyes and nasal passages. Nasal congestion is often associated with sleep disturbance, resulting in daytime fatigue and somnolence. An increased irritability and self-consciousness along with a decreased level of energy and alertness are frequently observed during pollen season [21]. Moderate and severe symptoms of Hay fever considerably impair learning ability in children, while adults suffer from work absences and reduced productivity [21, 22].

According to World Allergy Organisation (WAO) [22], Hay fever is increasing in prevalence and severity, and will continue to be a concern.

Around the world, in both developed and developing countries, environments are undergoing profound changes [3]. An increased air pollution and global warming own a substantial impact on respiratory health of the population. Ziska et al. [23] has already reported that the duration of ragweed pollen season has been increasing in recent decades in North America.

Any potential pattern changes, including prolonged pollen season, increased intensity of allergens or un-expected pollens detection directly affect the physical, psychological and social functioning of allergy sufferers [22]. The response to the external factors further differs among the individuals, which is particularly exacerbated in countries with high migration rates [3]. As for 2015, approx. 30% of the Australia’s Estimated Resident Population (ERP) was born overseas [24].

The ever-changing and unpredictable nature of Pollen allergies evolution necessitates the precise and timely statistics about the state of the condition.

The conventional, survey-based approaches involve a part of the population, and incur significant reporting delays (approx. 1 year in the case of official government reports [1]). Alternative approaches involve the number of hospital admissions and General Practitioners (GPs) reports of Hay fever instances. According to the study conducted in New South Wales — Australia [25], ’patients believe that Allergic rhinitis is the condition that should be self-managed’. Bypassing the Health Care Professionals (HCPs) and reliance on over-the-counter drugs can lead to statistics derived from services under-estimation. Also, the pharmacies supply data of oral antihistamines — the common Hay fever medicine — is used to indicate annually start and peak of the season [1, 2].

Despite insightful, such analyses are not conducted systematically as the collection of data from drug manufacturers/pharmacy outlets across the country is required. Finally, the pollen rates help in estimations of starting and peaking points of allergy seasons. Still, the actual condition prevalence may vary due to diverse responses to specific allergens among individuals.

Contributions

The main contributions of the study can be stated as follows:

  1. We introduce Deep Learning application in the context of Pollen Allergy surveillance from Social Media in put of currently dominant conventional Machine Learning classifiers;

  2. We propose the fine-grained classification into 4 classes in put of the most common binary classifiers, i.e.

    Hay Fever-related/Hay Fever-non-related;

  3. We focus on challenging informal vocabulary, which leads to condition under/over-estimation if unaddressed in put of the traditional limited keyword/lexicon-based approaches;

  4. We enrich the data with an extensive list of weather variables for potential patterns identification, where previous studies focus mainly on Temperature, and Pollen Rate.

Airborne pollen measurements are among the longest term datasets of biological origin, therefore representing a valuable proxy of ongoing climate change.

Extensive research over the final decade has shown that airborne pollen has increased in abundance but pollen seasons own also shifted to an earlier timeframe and may final longer (Ziello et al. 2012). It is still not clear, though, if this is the result of increased pollen production per floral unit or per individual plant, or the consequence of land use changes, ongoing climate change, eutrophication, global warming or a combination of these and numerous other factors. To date, some of the main causative factors for these changes own been considered air pollutants and higher air temperatures associated with global warming, or urbanisation rates and land use changes (e.g.

Voltolini et al. 2000; Sofiev et al. 2009).

In parallel with this, allergic reactions to pollen in sensitised individuals own increased in both frequency and severity over the final decades, which is in accordance with the above-mentioned increase in airborne pollen concentrations (Linneberg et al. 1999). Although the reason for this synchronicity is not thoroughly understood and the cause-effect relationship not completely sure, a correlation between pollen abundance and pollen sensitisation has been considered to be genuine (e.g. Troise et al. 1992; Ault 2004).

Overall, a extremely large number of factors are expected (but not limited) to be influenced by climate change (anthropogenic or not) and together to contribute to the exacerbated provocation of allergic symptoms in sensitised individuals.

There was an extensive review by Sofiev et al. in 2009 where the authors discuss plant-induced human allergy, from plant pollination and pollen dispersion to modelling and forecasting of airborne pollen concentrations. The following are some of the factors thought to be most significant, although the list cannot be exhaustive:

  1. Plant growth, as influenced by the combination of air pollutants (i.e. carbon dioxide) and elevated air temperature, because of increased plant biomass.

  2. Weather events, including drought or extreme rainfall, wind gusts, thunderstorms and any helpful of extreme micro- and macro-meteorological effects.

  3. Plant microbiome (plant, leaf, inflorescence and pollen microbiome), as sure by a wide variety of environmental factors, including biodiversity per se and its temporal variability.

  4. Pollen production, as expressed by increased pollen or flower production per inflorescence, or by a higher number of inflorescences per plant.

  5. Onset and duration of the pollen season, as influenced by meteorological and climatic factors, per site, among sites and among years and for each pollen type.

  6. Pollen allergenicity, as influenced by air pollutants (e.g.

    ozone and nitrogen dioxide) and air temperature, but, notably, in inverse correlation to pollen production per plant, after taking into account available resources as a limiting factor.

  7. Pollution, including air, water, soil and other forms of pollution, on various spatial and temporal scales.

  8. Land use changes, land management, habitat fracturing and moving to the north because of global warming.

Plant phenological traits (like flowering, leaf and bud formation, fruit and pollen production) are well known to be extremely sensitive to environmental stress and especially to temperature variability.

This is particularly true for flowering and pollen production (e.g.

What is the best over the counter medicine for pollen allergies

Damialis et al. 2011; Menzel et al. 2006; Parmesan and Yohe 2003).

What is the best over the counter medicine for pollen allergies

There own been strong indications that plants produce more pollen, and earlier, when temperatures are higher, that is, at urban locations, lower elevations or southern exposure slopes, or during warmer years (e.g. Damialis et al. 2011; Fotiou et al. 2011). Higher rainfall prior to the inflorescence production and pollen formation and liberation also favour increased pollen and flower production (Damialis et al. 2011).

What is the best over the counter medicine for pollen allergies

However, the implicated processes are excessively complicated and influence of numerous other factors is involved, for example microclimatic conditions in the examined site. Likewise, temperature seems to own a direct effect on allergen release, as revealed by the inter-annual variability in a study on birch pollen in Germany (Buters et al. 2008).

Air pollutants are also responsible for higher biomass production (including flower and pollen production). Wan et al. (2002) and Wayne et al. (2002) experimentally found that, especially in combination with elevated air temperature, increased carbon dioxide (CO2) did not alter pollen production per se, but increased plant biomass in Ambrosia artemisiifolia and, consequently, individual plants produced more pollen.

Ziska et al. (2003) studied the same species but in real-life conditions in a gradient simulating diverse climatic scenarios and, likewise, found that plants exhibited higher biomass, pollen production and earlier flowering dates. Ziska et al. (2003) additionally concluded that plant expansion rates and regional abundance may also increase with increasing CO2, thus increasing allergenic pollen exposure rates on a wider spatial scale.

Air pollution and climate change do not only affect plant growth, pollen and flower production, and duration of the whole pollen season, but can also display more direct health effects by increasing the quantity of allergenic proteins of the pollen (Zhao et al.

2016, 2017). According to Zhao et al. (2016), elevated levels of certain pollutants, love nitrogen dioxide (NO2), which is traffic-related and hence more prevalent in urban locations, increase overall pollen allergenicity, thus also increasing the relevant allergy risk for sensitised individuals. El Kelish et al. (2014), as well as Zhao et al. (2017), showed that elevated pollutants change the transcriptome of ragweed pollen; therefore, under global change scenarios, the allergenic potential of pollen is also expected to change. Vehicular-exhaust pollution has been reported to influence the allergenicity of ragweed pollen: pollen along high-traffic roads showed an overall higher allergenicity than pollen from low-traffic roads and vegetated areas (Ghiani et al.

2012). Beck et al. (2013) documented a positive relationship between atmospheric ozone (O3) levels and the quantity of Bet v 1 in pollen samples collected from birch trees in outdoor stands in Bavaria, Germany. However, further clarification is needed regarding what the combined effect of ozone, nitrogen dioxide, carbon dioxide and air temperature on pollen allergenicity is on a plant population or ecosystem level. Epidemiological studies own demonstrated that urbanisation, high levels of vehicle emissions and a Westernised lifestyle are correlated with an increase in the frequency of pollen-induced respiratory allergy, which is more prominent in people who live in urban areas compared to those who live in rural areas (Haftenberger et al.

2013).

Immune system response to a substance that most people tolerate well

For the medical journal of this title, see Allergy (journal).

Allergy
Hives are a common allergic symptom
Specialty Immunology
Symptoms Red eyes, itchy rash, runny nose, shortness of breath, swelling, sneezing[1]
Types Hay fever, food allergies, atopic dermatitis, allergic asthma, anaphylaxis[2]
Causes Genetic and environmental factors[3]
Diagnostic method Based on symptoms, skin prick test, blood test[4]
Differential diagnosis Food intolerances, food poisoning[5]
Prevention Early exposure to potential allergens[6]
Treatment Avoiding known allergens, medications, allergen immunotherapy[7]
Medication Steroids, antihistamines, epinephrine, mast cell stabilizers, antileukotrienes[7][8][9][10]
Frequency Common[11]

Allergies, also known as allergic diseases, are a number of conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment.[12] These diseases include hay fever, food allergies, atopic dermatitis, allergic asthma, and anaphylaxis.[2] Symptoms may include red eyes, an itchy rash, sneezing, a runny nose, shortness of breath, or swelling.[1]Food intolerances and food poisoning are separate conditions.[4][5]

Common allergens include pollen and certain foods.[12] Metals and other substances may also cause problems.[12] Food, insect stings, and medications are common causes of severe reactions.[3] Their development is due to both genetic and environmental factors.[3] The underlying mechanism involves immunoglobulin E antibodies (IgE), part of the body’s immune system, binding to an allergen and then to a receptor on mast cells or basophils where it triggers the release of inflammatory chemicals such as histamine.[13] Diagnosis is typically based on a person’s medical history.[4] Further testing of the skin or blood may be useful in certain cases.[4] Positive tests, however, may not mean there is a significant allergy to the substance in question.[14]

Early exposure to potential allergens may be protective.[6] Treatments for allergies include avoiding known allergens and the use of medications such as steroids and antihistamines.[7] In severe reactions injectable adrenaline (epinephrine) is recommended.[8]Allergen immunotherapy, which gradually exposes people to larger and larger amounts of allergen, is useful for some types of allergies such as hay fever and reactions to insect bites.[7] Its use in food allergies is unclear.[7]

Allergies are common.[11] In the developed world, about 20% of people are affected by allergic rhinitis,[15] about 6% of people own at least one food allergy,[4][6] and about 20% own atopic dermatitis at some point in time.[16] Depending on the country about 1–18% of people own asthma.[17][18] Anaphylaxis occurs in between 0.05–2% of people.[19] Rates of numerous allergic diseases appear to be increasing.[8][20] The expression «allergy» was first used by Clemens von Pirquet in 1906.[3]


Pollen count

How do scientists know how much pollen is in the air?

They set a trap. The trap — generally a glass plate or rod coated with adhesive — is analyzed every few hours, and the number of particles collected is then averaged to reflect the particles that would pass through the area in any 24-hour period. That measurement is converted to pollen per cubic meter. Mold counts work much the same way.

A pollen count is an imprecise measurement, scientists confess, and an arduous one — at the analysis stage, pollen grains are counted one by one under a microscope. It is also highly time-consuming to discern between types of pollen, so they are generally bundled into one variable.

Given the imprecise nature of the measurement, entire daily pollen counts are often reported simply as low, moderate or high.

The American Academy of Allergy, Asthma & Immunology provides up-to-date pollen counts for U.S. states.


Common allergens

The most common allergen is pollen, a powder released by trees, grasses and weeds that fertilize the seeds of neighboring plants. As plants rely on the wind to do the work for them, the pollination season sees billions of microscopic particles fill the air, and some of them finish up in people’s noses and mouths.

Spring bloomers include ash, birch, cedar, elm and maple trees, plus numerous species of grass.

Weeds pollinate in the tardy summer and drop, with ragweed being the most volatile.

The pollen that sits on brightly colored flowers is rarely responsible for hay fever because it is heavier and falls to the ground rather than becoming airborne. Bees and other insects carry flower pollen from one flower to the next without ever bothering human noses.

Mold allergies are diverse. Mold is a spore that grows on rotting logs, dead leaves and grasses.

While dry-weather mold species exist, numerous types of mold thrive in moist, rainy conditions, and release their spores overnight. During both the spring and drop allergy seasons, pollen is released mainly in the morning hours and travels best on dry, warm and breezy days.


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