Sneezing is a common reaction that forces air through the nose and mouth. When the tissues of the nasal cavity are irritated, sneezing is an act that helps clear the cavity. This is a reaction that cannot be controlled and results in an explosive sound too.
Some people sneeze when they are suddenly exposed to a light source.
Reflexive sneezing that is induced by sunlight or other bright lights is called photic sneeze reflex.
Experts say that the photic sneeze reflex causes sneezing when people experience variations in the intensity of light.
Photic sneeze reflex is also called photosneezia or Autosomal Dominant Compelling Helio-Ophthalmic Outburst (ACHOO) syndrome.
About 10-35% of people in the world suffer from photic sneeze reflex.
White women seem to be at more risk for developing photic sneeze reflex. A study amongst 367 patients reported that 94.3% of photic sneezers were Caucasian (white) individuals and 67% of them were women. This study also mentioned that 90.7% of these individuals had three or lesser sneezes on sudden exposure to light. Only 12.3% of people had continuous reactions on exposure to light.
The primary symptom of photic sneeze is sneezing when exposed to light. Most individuals don’t have extended reactions to light. They only react when they suddenly move from a dark space to a lit space. The number of sneezes ranges from 1-10.
The ZEB2 gene helps make a protein that plays a role in forming the nerve cells before birth. This protein is also important in making vital parts of the body like the kidneys and skeletal muscles.
rs10427255
The rs10427255 SNP is located near the ZEB2 gene. The minor C allele is the risk allele of this SNP and is associated with an increased risk for developing photic sneeze reflex.
Deviated nasal septum - The nasal septum is the thin wall that gives structure to your nose. Some people’s nasal wall gets displaced or moves from the original place because of certain injuries. The risk for developing photic sneeze is high in people with a deviated nasal septum.
Use of tobacco - A certain study relates the use of tobacco with light-induced episodes of sneezing.
Optic nerve response - Some scientists believe that when the optic nerve is exposed to sudden light sources, it creates similar reactions in the body, like when the nose is irritated. This can cause episodes of sneezing.
Eye injections - In some cases, people end up having photic sneezing when they are given eye injections. These injections trigger the trigeminal nerve. This is one of the cranial nerves that give sensations to the various parts of the face. Triggering the nerve causes sneezing.
Prominent corneal nerves - According to a small study conducted, 67% of people with some degree of prominent corneal nerves experienced photic sneezing.
Cover your eyes - When you are stepping out in the sun, wear sunglasses to prevent direct exposure to sunlight. This is a very easy trick to prevent the flaring up of sneezes. You can also wear hats and scarves to bring down the intensity of sunlight.
Philtral Pressure Technique (PPT) - When you apply pressure to the sub-philtral region, it is said to help stop sneezing. The philtrum is the region between the nose and the upper lips. When you press this region gently with the index finger, this brings down the urge to sneeze.
When you press the philtrum region, this stimulates the mechanoreceptors. These receptors send signals to the brain when stimulated by an external medium (touch, in this case). These mechanoreceptor signals override the signals caused by trigeminal nerve stimulation and hence prevent sneezing.
Antihistamine sprays and drugs - Even though photic sneeze is not an allergic reaction, it seems to get better with antihistamine sprays and drugs.
https://www.bbc.com/future/article/20150623-why-looking-at-the-light-makes-us-sneeze
https://pubmed.ncbi.nlm.nih.gov/7673597/
https://www.healthline.com/health/photic-sneeze-reflex#risks
https://www.nature.com/articles/s41433-019-0368-4
https://www.nature.com/articles/s41598-019-41551-0
https://www.pbs.org/newshour/science/does-the-sun-make-you-sneeze
https://medlineplus.gov/genetics/gene/zeb2/
https://www.snpedia.com/index.php/Rs10427255
One look at a cockroach walking on your kitchen floor or slab, and you rush to get it right out of your home! Cockroaches are icky pests that are known to spread germs and cause diseases. But, did you know, just like other animals, birds, and pollen, people can be allergic to cockroaches too?
You will be shocked to know that around 78%-98% of homes in urban areas contain cockroaches, and about 60% of the people with asthma who live in cities are allergic to cockroaches. A protein found in cockroaches triggers an allergic reaction in some people.
Like any allergy, cockroach allergy gets triggered by an allergen, often an enzyme (a type of protein) released from the body of roaches. This allergen is found in the cockroach’s saliva, waste, and body parts and spreads everywhere the cockroach goes. Coming in contact with these cockroach proteins can trigger an allergic reaction.
In people who are allergic to cockroaches, common symptoms include:
- Uncontrolled sneezing
- Runny or stuffy nose
- Itchy, red, and watery eyes
- Itchiness in throat, mouth, and nose
- Cough
- Skin itch and skin rash
In asthmatics, symptoms of cockroach allergy include:
- Wheezing
- Chest tightness
- Breathing trouble
- Whistling sound while breathing out
Cockroach allergy has been reported as an important cause of asthma for over 50 years. Many studies that have been conducted so far establish a positive correlation between cockroach allergy and the development of asthma. The main reason for this is environmental exposure and sensitization to the various species of cockroaches that exist in the world today. In fact, this sensitization to cockroach allergens is the biggest risk factor for the development of asthma in low-income populations in urban setups.
There are many genes and polymorphisms that have strong associations with this condition, particularly the genetic variants in TSLP, MBL2, CD14, and IL-12A genes.
One particular gene, the IL-12A or Interleukin 12, and its variants influence cockroach allergy in children with asthma. IL-12A is involved in immune responses, especially the one involving T cells. IL-12A also has a role to play in the pathogenesis of asthma. The gene is located on the p-arm of chromosome 3.
Variations in The IL-12A Gene
Two SNPs, rs2243123 and rs2243151, associated with the IL-12A gene, have shown a risk of increased allergic susceptibility to different species of cockroaches
The presence of the T allele in SNP rs2243123 is associated with an increased risk of cockroach allergy with respect to the two common cockroach species P. Americana and B. germanica.
The presence of the A allele in SNP rs2243151 is associated with an increased risk of cockroach allergy.
From the many studies performed on cockroach allergy and its association with asthma, non-genetic risk factors that increase one’s risk of developing the cockroach allergy include:
Low socio-economic status: People from low socio-economic segments living in urban cities are at an increased risk of developing cockroach allergy as they are exposed to cockroaches more often and get sensitized to them.
Race: African-Americans are at an increased risk of developing the condition.
Pre-existing asthma: People who have atopic or other types of asthma are at an increased risk of developing cockroach allergy. In fact, cockroach allergy is the most common indoor allergy that asthmatics suffer from.
Lifestyle modifications:
Individuals who are allergic to cockroaches need to make a few lifestyle modifications to avoid cockroaches as much as they can. Here’s what you can do:
- Always cover all your trash/garbage bins.
- Keep food, both cooked and uncooked, in airtight containers with proper lids.
- Clean up any food spills, crumbs, oil, etc., from the stovetop, counters, tables, and floor as these can attract cockroaches.
- Cockroaches like damp places. So, look out for any leaking pipes in your home and seal any cracks in the floor or walls from where cockroaches can enter the house.
- Use anti-cockroach sprays, gels, and traps to drive out or kill existing cockroaches from your house.
Cockroaches are common members in most homes, and an allergy to them is a very common occurrence too. If you suspect you have a cockroach allergy, or your symptoms seem to be getting worse, visit your doctor immediately to help bring it under control. A simple blood test or skin test can help diagnose if you or your loved one is allergic to cockroaches.
https://www.aafa.org/cockroach-allergy/https://acaai.org/allergies/types/cockroach-allergy
https://pubmed.ncbi.nlm.nih.gov/8648037/
https://www.jacionline.org/article/S0091-6749(96)70209-9/fulltext
https://www.healthline.com/health/cockroach-allergy#bottom-line
https://www.webmd.com/allergies/nasal-allergy-trigger-cockroaches
https://www.nationaljewish.org/conditions/allergy/overview/allergens/cockroach
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2525650/
House Dust Mites or dust mites belong to the spider family and are small and microscopic beings present everywhere. They are 1/3rd of a millimeter in size and look like a small white bug.
Did you know that dust mites are present all over the world except in Antarctica? If you seem to have allergic reactions all through the year, then it could mean that you are allergic to dust mites.
Dust mites love humid and slightly warm temperatures and have strong survival skills. While there are up to 13 types of dust mites present, the three common types that could be present in your house are:
1. American house dust mites
2. European house dust mites
3. Mayne’s house dust mites
House mites feed on the dead skin flakes of humans and other animals. Since human beings shed 30,000-40,000 dead skin cells every minute, there is always so much food for dust mites to eat, flourish, and reproduce.
About 100,000 dust mites live in each square yard of your home carpet. The mattresses you sleep in have hundreds of thousands of dust mites happily living and reproducing.
If your pillow is 2+ years old, up to 10% of the weight of your pillow could be from dust mites and their droppings!
People are usually not allergic to live dust mites. However, they react negatively to the droppings of these mites and the dead bodies of these mites. Every dust mite leaves behind at least 20 droppings a day. Imagine your mattress having 500,000 dust mites. That means every day, your mattress is filled with 10,000,000 new mite droppings!
Each dust mite can live for about 2-3 months. Female dust mites lay 60-100 eggs during their lifespan. As a result, the number of dust mites in your house multiplies every day.
This is the reason people’s allergic reactions to dust mites increase with time.
If you are allergic to the dead mites and droppings of dust mites, then you can have the below allergic reactions.
- Sneezing
- Watery eyes
- Red and itchy eyes and nose
- Postnasal drip (dripping flow of mucus from the nose to your throat)
- Itchy and red skin
- Coughing and wheezing
- Shortness of breath
The IL10 gene produces the interleukin 10 protein. This protein plays a role in bringing down inflammation in the body. This is considered a good gene and brings down the unwanted effects of immune responses.
[The GG genotype of the rs3024496 SNP of this gene brings down the activity of the interleukin 10 protein and hence increases the risk of asthma when exposed to dust mites] (https://www.jacionline.org/article/S0091-6749(08)00599-X/fulltext).
rs117902240
The AC genotype of the rs117902240 SNP decreases FEV1 capacity and increases the risk of asthma attacks when exposed to excessive dust mites. FEV1 is a measure of a person’s vital capacity.
rs115997623
The minor T allele of the rs115997623 SNP is considered risky and is associated with reduced FEV1 function and an increased risk for asthma attacks with exposure to dust mites.
Industrial settings: People who live in highly industrialized areas are exposed to more dust pollution and dust mites. These individuals have a higher chance of developing dust mite allergy.
Heredity: Though rare, dust mite allergy can run in the family. If your grandparents or parents have had dust mite allergies, the chances are that you develop it too.
Age: Infants and children are at higher risk for developing dust mite allergies than adults.
Exposure to excessive dust mites early in life: If a person has been exposed to excessive dust mites very early in life, he/she is at more risk for developing a dust mite allergy.
Smoking: Cigarette smoking can damage the airway epithelial cells. The airway epithelium is a column-like structure in the respiratory tract that prevents allergens and external elements from entering the tract. Tobacco smoke kills these cells and makes you vulnerable to dust mites. [Smoking also worsens symptoms of dust mite allergies] (https://pubmed.ncbi.nlm.nih.gov/10340943/).
Asthma and other allergies: 75% of children and 50% of adults with asthma are also diagnosed with other forms of allergies. Up to 85% of people with asthma and other allergies end up being allergic to house mites. This relationship between these different kinds of allergies makes it difficult to treat the underlying condition.
Confirm dust mite allergy
There are so many substances that can cause allergies and it is important to understand if you are allergic to dust mites. Here are some tests/diagnostic methods that help with the confirmation:
- IgE blood test - This blood test looks for IgE antibodies in the blood to identify if the person is having an adverse reaction to dust mites.
- Skin prick test - Exposes the skin to a small amount of dust mite allergen and checks the reactions.
- Atopic patch tests - Atopic patch tests make use of delayed reactions and the presence of T cells in the body to diagnose dust mite allergies.
- Basophil activation tests - Basophils are types of White Blood Cells that fight against external allergens. These tests look for basophil activation markers to know if a person is having an allergic reaction to dust mites.
Cover mattresses and pillows with thicker fabrics and plastic sheets
By covering mattresses with plastic sheets in the morning, you can prevent the penetration of dust mites into the mattress surface. Thicker and finely woven fabric covers in the night prevent dust mites from penetrating from the mattress to your body.
Don’t use carpets unless necessary
If not needed, carpets can be removed from floors, as this helps bring down dust mite growth at home.
Wash bedding in hot water
Make sure you wash your bedding at least once a week in hot water to kill dust mites. Drying the bedding in bright sunlight also helps kill existing mites.
Use air filters
Air filters or air purifiers come with HEPA (high-efficiency particulate air) filtration system and can eliminate microscopic dust mites and their particles from the room.
Use dehumidifiers
Dehumidifiers are appliances that help bring down the humidity levels in a room. If you live in a humid area, using these can help bring down the growth of dust mites.
Acaricide cleaners
Acaricides are kinds of pesticides used in killing dust mites and ticks. These are toxic in nature and need to be used with caution. Most people take the help of professional cleaners who use acaricide based products to get rid of mites.
Antihistamine sprays and drugs
Since dust mites cause general allergic reactions in the body, treating the reactions with antihistamine sprays and over the counter drugs help.
House dust mites allergen immunotherapy
This immunotherapy practice is also called desensitization. This involves injecting minute doses of the allergen (dust mites in this case) to the individual over a period of time to decrease sensitivity.
The injections are offered in regular periods for around 24 weeks, and this will be followed by 3-5 years of monthly maintenance schedules. This process gives permanent relief and reduces the flaring up of dust mite allergic symptoms.
https://www.ncbi.nlm.nih.gov/books/NBK447098/
https://www.mayoclinic.org/diseases-conditions/dust-mites/symptoms-causes/syc-20352173
https://www.healthline.com/health/allergies/dust-mites#treatment
https://www.aafa.org/dust-mite-allergy/
https://acaai.org/allergies/types/dust-allergy
Misophonia means “hatred of sound” in Greek. Also called selective sound sensitivity syndrome, misophonia is the dislike or hatred of certain sounds to an extent where it interferes with daily lifestyle. It is a neurological condition that has both psychological and physiological symptoms.
Everyone gets occasionally irritated by certain sounds like chewing or clicking a pen. For people with misophonia, these sounds cause a severe reaction in them. They have very strong emotional reactions and physiological distress. The sensitivity to sound can cause a fight-or-flight response in people and interfere with their everyday lives. Emotional reactions like anxiety, rage, panic, anger, and hatred are triggered by this condition. This can also turn into verbal and physical aggression, avoidance, isolation, and depression.
The reaction is an involuntary physical and emotional reflex triggered by the sound. It activates the autonomic nervous system located in the brain and the limbic system associated with emotion. This results in emotional distress and the fight or flight response, which involves sweating, rapid heartbeat, and hormonal changes, among other symptoms. This reaction usually happens immediately within seconds of hearing the sound. The symptoms are instant and huge and take over cognitive functioning.
People with misophonia are often misdiagnosed as having anxiety or other disorders. This is because misophonia related research is fairly new. A lot of studies are being done to understand the condition better and establish more facts about it. It is not included in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), which is the main resource for diagnosing mental disorders in the United States. There is an International Misophonia Network that lists doctors with knowledge of misophonia to help with the condition.
The triggering sounds may vary over time and among different people. Almost any sound can be a potential trigger. The common triggers that cause misophonia are:
- Sounds related to the mouth like smacking lips, slurping, throat clearing, chomping, and swallowing
- Loud breathing sounds
- Clicking pens
- Papers rustling
- Clocks ticking
- Sounds of some animals
- Slamming car doors
- Certain visual triggers include wagging feet, twirling hair
Since misophonia-related research is fairly new, many health professionals cannot easily differentiate between it and other related conditions. A few characteristics of misophonia include:
1. More women have misophonia than men.
2. The symptoms are first seen between the ages of 9 to 12 in most people. The onset of this condition is generally before puberty.
3. The first reaction is usually triggered by a specific sound from a parent or other family members, and this intensifies over time, and new triggers arise.
4. People with this condition tend to have a higher IQ.
Misophonia is more common in women than in men. About 15-20% of adults with European ancestry were found to suffer from this condition. This indicates that there’s a genetic link to misophonia.
A genetic marker located near the TENM2 gene involved in brain development is associated with the feeling of rage at trigger sounds.
The TENM2 gene encodes a protein called Teneurin-2. This protein is involved in neural development and neuronal connectivity.
rs1837253
rs1837253 is an SNP found in the TENM2 gene. The G allele of this SNP is the risk allele and is associated with an increased risk of the condition.
This is a lifelong disorder with no specific cure. However, the symptoms can be managed by following several measures.
- Try to actively avoid triggers as repeated exposure to the trigger can make the response worse.
- Maintaining good health, both emotional and physical, and help lessen the severity of the response for a trigger.
- Counseling: This can definitely help people manage their symptoms better and lead a normal lifestyle. Misophonia can have a negative impact on the people around you, too, as you display severe emotional and physical distress. Support is needed for both the person with the condition and their family. Misophonia Interantional, an advocacy and networking organization, provides a lot of useful information regarding this condition, including managing this condition and connecting with several researchers and trained professionals.
- Cognitive behavioral therapy: This may help change the negative associations linked to triggering noises. Audio of rain, nature, or other sounds are streamed using ear-level devices, and this helps most people experience a relief in symptoms.
- Treating tinnitus can help people tolerate triggering noises better.
https://www.healthline.com/health/misophonia
https://www.webmd.com/mental-health/what-is-misophonia#1
https://www.medicalnewstoday.com/articles/320682
https://misophoniainstitute.org/what-is-misophonia/
https://www.misophoniainternational.com/
https://www.snpedia.com/index.php/Rs2937573
https://www.23andme.com/topics/traits/misophonia/
https://rarediseases.info.nih.gov/diseases/12058/misophonia
[In the United States, about 62% of households have pets] (https://www.aaaai.org/conditions-and-treatments/allergies/pet-allergy). At the same time, millions of Americans are allergic to pets.
The most common pet allergen is dander, the dead skin shed by pets. Other allergens include proteins found in the pet’s urine and saliva. The overreaction of the immune system results in an allergic reaction. The immune system recognizes the protein in the animal’s skin, saliva, or urine as foreign and produces histamine and other chemicals that lead to the symptoms of an allergy.
The pet allergens can even be found in homes that don’t have pets, as you can carry them on your clothing. The allergens can be found on furniture and walls. They spread through the air whenever the animal is petted or groomed, and can stay airborne for a long time.
Signs and symptoms are usually very mild and can be easily managed. The allergy can be life-threatening in rare cases where there is a severe allergic reaction like anaphylaxis. This impairs breathing and can send the body into shock if immediate action is not taken. Anaphylaxis can also lead to cardiac arrest.
Cats and dogs are the leading cause of pet allergies. Other animals like rodents and rabbits can also cause allergies. Animals without fur, rarely cause allergies.
The symptoms vary from person to person and can usually occur immediately after consumption or after a few hours. The symptoms are common to those seen in other allergic reactions.
- Runny or stuffy nose
- Nasal congestion causing pain
- Coughing
- Wheezing
- Hives
- Watery, red, or itchy eyes
- Anaphylaxis in severe cases
- Difficulty breathing
- Eczema
- Itchy skin
Variations in certain genes have been observed in people with pet allergies. Studying these variations can help predict if a person has a higher risk of getting the allergy compared to other people.
The HLA-DQB1 gene is part of the family of genes that form the human leukocyte antigen (HLA) complex. The proteins produced by these genes play an important role in the immune system of the body. They help in distinguishing between self and foreign proteins and trigger the necessary immune response.
Variations in this gene are found to be associated with asthma and allergic rhinitis.
rs7775228
rs7775228 is an SNP found in the HLA-DBQ1 gene. People with the minor allele, the C allele, are found to have an increased risk of asthma, and [allergic rhinitis] (https://pubmed.ncbi.nlm.nih.gov/22036096/).
The C allele has also been associated with increased sensitivity to dog allergens.
The LRRC32 gene encodes for a membrane protein that contains 20 leucine-rich repeats. It regulates a key regulator of a growth factor called TGF-B, which is involved in several functions of the immune system.
rs2155219
rs2155219 is an SNP found in the LRRC32 gene. People with the minor allele, G allele are found to have a 1.18X increased risk of allergic sensitization. The TT genotype is found to be associated with allergic rhinitis.
If one or both the parents have any allergies or asthma, the child is more likely to develop a pet allergy.
Skin-prick test: A small amount of purified allergen extract is pricked into the skin on the forearm or back. After 15-20 minutes, if signs of allergy like redness or itching are observed, you’re found to be allergic to that specific allergen.
Blood test: Blood samples are tested for the presence of allergic antibodies against proteins found in pet dander, urine, or saliva. This can indicate how sensitive you are to an allergen.
The best way to manage any allergy is to avoid the allergen causing it. This can prevent severe allergic reactions.
Lifestyle:
If you decide to give away your pet, you still need to thoroughly clean your house to get rid of all the allergens. Replace carpets, bedding, upholstered furniture, and vacuum your entire house with HEPA filters.
If you still want to keep your pet, there are certain measures you can take to avoid an allergic reaction.
1. Ask someone else you live with who does not have allergies to give frequent baths to your pet, at least once a week.
2. Make your bedroom a pet-free zone as you would spend most of your time there. This prevents allergens from settling on things in the room.
3. Use air purifiers with HEPA filters to remove allergens in the air. Vacuum your house frequently with machines containing HEPA filters.
4. Remove any furniture, upholstery, and curtains that can collect dander easily. Try to avoid carpets also.
5. Wear a dust mask if you cannot find anyone to help with cleaning your pet.
6. Clean the pet’s kennel, litter box frequently. It would be better if someone without allergies can help with this.
Studies show that being exposed to pets early in life can help avoid allergies.
Medications:
You may need to take allergy medications in addition to taking measures to avoid the allergen. Your doctor may prescribe any of the following medications based on your case:
- Antihistamines
- Decongestants
- Corticosteroids
- Leukotriene modifiers
Treatments:
1. Immunotherapy: This is done through a series of allergy shots. Small doses of allergen are given as weekly shots, and the dosage is gradually increased to get your immune system used to the allergen.
2. Nasal irrigation: A specially designed squeeze bottle or a neti pot can be used to flush the allergen and thickened mucus out of your sinuses. A prepared saline solution is used.
https://www.niehs.nih.gov/health/topics/agents/allergens/pets/index.cfm
https://www.aafa.org/pet-dog-cat-allergies/
https://acaai.org/allergies/types/pet-allergy
https://www.mayoclinic.org/diseases-conditions/pet-allergy/symptoms-causes/syc-20352192
https://www.ncbi.nlm.nih.gov/pubmed/23817569
https://www.snpedia.com/index.php/Rs7775228
https://www.snpedia.com/index.php/Rs2155219
Contact dermatitis is a reaction that occurs when you touch or come in contact with certain substances (typically an allergen or irritant). When your skin comes into contact with substances that you’re allergic or sensitive to, it can become red, itchy, and irritated. These substances include certain chemicals present in skincare products, detergents, jewelry made of certain metals, and poison ivy. Contact dermatitis usually presents as a rash on your skin in the affected area. The protective layer of your skin gets damaged, dry, cracked, and forms blisters. Most reactions aren’t severe and can be easily managed or treated completely.
The general symptoms include:
- Swelling
- Redness
- Skin irritation
- Bumps, blisters (rarely)
- Itching or burning
- Tender skin
The symptoms can vary based on the type of contact dermatitis. They can be mild or severe and can appear immediately on contact or a few days later. Contact dermatitis is not contagious. The hands are known to be the most common part affected by contact dermatitis.
Variations in certain genes are found to increase a person’s risk of contact dermatitis. The risk for contact dermatitis runs in families. It can be passed down through generations. Research is still being done to establish further relations between genetics and contact dermatitis.
The TNF gene encodes the Tumor Necrosis Factor, which is a proinflammatory cytokine found in immune cells. This is mainly involved in the chronic inflammation process in the body. This gene has been implicated in various conditions like asthma, heart disease, and liver disease.
Repeated exposure to allergens leads to inflammation of the skin. This is called the elicitation phase. TNF plays an important role in this phase of allergic contact dermatitis.
rs1800629
rs1800629 is an SNP found in the TNF gene. The A allele leads to increased production of TNF and a higher risk of developing allergic contact dermatitis compared to the G allele, which is the major allele.
rs361525
This SNP is also found in the TNF gene. Individuals with the A allele are less prone to develop dermatitis of the hands, suggesting a protective effect of the A allele.
If you have sensitive skin, do a patch test or spot test before using any new product. A patch containing the product or the product itself is applied on a spot in the forearm and covered. Avoid using water or soap near the spot for 48 - 96 hours. If there’s any reaction like redness or itching, the product contains a potential allergen or irritant and should be avoided.
https://www.healthline.com/health/contact-dermatitis#symptoms
https://www.webmd.com/skin-problems-and-treatments/contact-dermatitis#2
https://www.ncbi.nlm.nih.gov/pubmed/28300283
https://www.verywellhealth.com/contact-dermatitis-causes-83205
https://www.snpedia.com/index.php/Rs1800629
https://pubmed.ncbi.nlm.nih.gov/18620134/
https://www.ncbi.nlm.nih.gov/gene/2312
https://pubmed.ncbi.nlm.nih.gov/23374260/
https://www.snpedia.com/index.php/Rs61816761
https://onlinelibrary.wiley.com/doi/abs/10.1111/cod.12362
