And some people develop a tolerance to the substance over time. Allergic contact dermatitis occurs when a substance to which you're sensitive allergen triggers an immune reaction in your skin.
It usually affects only the area that came into contact with the allergen. But it may be triggered by something that enters your body through foods, flavorings, medicine, or medical or dental procedures systemic contact dermatitis. You may become sensitized to a strong allergen such as poison ivy after a single exposure. Weaker allergens may require multiple exposures over several years to trigger an allergy.
Once you develop an allergy to a substance, even a small amount of it can cause a reaction. Children develop the condition from the usual offenders and also from exposure to diapers, baby wipes, sunscreens, clothing with snaps or dyes, and so on.
Contact dermatitis can lead to an infection if you repeatedly scratch the affected area, causing it to become wet and oozing.
This creates a good place for bacteria or fungi to grow and may cause an infection. Hand-washing is essential for preventing the spread of germs. But, sometimes, all this scrubbing can cause a rash. Does this mean you're allergic to the soap? Davis says allergic dermatitis means a substance is causing an allergic reaction on your skin. But irritant contact dermatitis means your skin is inflamed from repeated exposure to something.
Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. This content does not have an English version. This content does not have an Arabic version. Overview Contact dermatitis on the wrist Open pop-up dialog box Close. Contact dermatitis on the wrist Contact dermatitis can appear as an itchy, red rash. Contact dermatitis on the face Open pop-up dialog box Close. Contact dermatitis on the face Contact dermatitis usually affects areas of skin directly exposed to an offending substance.
Allergies often occur along with other diseases, such as asthma , ear infections , sinusitis , and sleep apnea. For more information, see the topic Allergic Rhinitis.
There are many types of allergies. Some of the more common ones include:. Seasonal allergies show up at the same time of the year every year and are caused by exposure to pollens from trees, grasses, or weeds.
Hay fever is the most common seasonal allergy. Allergies that occur for more than 9 months out of the year are called perennial allergies.
Year-round symptoms chronic allergies are most likely to occur from exposure to animal dander , house dust, or mould.
Check your symptoms to decide if and when you should see a doctor. Health Tools help you make wise health decisions or take action to improve your health. Many things can affect how your body responds to a symptom and what kind of care you may need. These include:. You have answered all the questions. Based on your answers, you may be able to take care of this problem at home. Symptoms of infection may include:. Symptoms of a severe allergic reaction can start within minutes of eating or being exposed to an allergen.
While symptoms usually occur within 2 hours, in rare cases the time frame can vary up to several hours after exposure. Symptoms can include any of the following:. A severe reaction can take place without hives, so make sure to look out for all of the signs of an allergic reaction. Symptoms of difficulty breathing can range from mild to severe. For example:. Certain health conditions and medicines weaken the immune system's ability to fight off infection and illness.
Some examples in adults are:. Shock is a life-threatening condition that may quickly occur after a sudden illness or injury. Adults and older children often have several symptoms of shock. Shock is a life-threatening condition that may occur quickly after a sudden illness or injury. Babies and young children often have several symptoms of shock. Based on your answers, the problem may not improve without medical care. Based on your answers, you may need care soon.
The problem probably will not get better without medical care. Based on your answers, you may need care right away. The problem is likely to get worse without medical care. Based on your answers, you need emergency care.
Call or other emergency services now. If you have an epinephrine shot, use it while you wait for help to arrive. Follow the directions on the label about how to give the shot. Sometimes people don't want to call They may think that their symptoms aren't serious or that they can just get someone else to drive them.
But based on your answers, the safest and quickest way for you to get the care you need is to call for medical transport to the hospital. You can use home treatment to relieve symptoms of:. Try a non-prescription medicine for the relief of itching, redness, and swelling. Be sure to follow the non-prescription medicine precautions. For tips on how to treat dry and irritated skin, see the topic Dry Skin and Itching. For information on how to treat an insect bite or sting, see the topic Insect Bites and Stings and Spider Bites.
Call your doctor if any of the following occur during home treatment:. To prevent problems with severe allergic reactions:. To prevent seasonal or year-round allergy reactions:.
You can help your doctor diagnose and treat your condition by being prepared to answer the following questions:. This information does not replace the advice of a doctor.
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British Columbia Specific Information Symptoms of a severe allergic reaction Anaphylaxis can start within minutes of eating or exposure to an allergen a substance capable of causing an allergic reaction.
Topic Overview Allergies are an overreaction of the body's natural defence system that helps fight infections immune system. Types of allergies There are many types of allergies. Some of the more common ones include: Food allergies, which are more common in children than adults.
Food allergies are most common in people who have an inherited tendency to develop allergic conditions. These people are more likely to have asthma and other allergies.
For more information, see the topic Food Allergies. Medicine allergies. Many prescription and non-prescription medicines can cause an allergic reaction. Allergic reactions are common and unpredictable.
The seriousness of the allergic reaction caused by a certain medicine will vary. Allergies to insect venom. When you are stung by an insect, poisons and other toxins in the insect's venom enter your skin. It is normal to have some swelling, redness, pain, and itching at the site of a sting. An allergic reaction to the sting occurs when your body's immune system overreacts to the venom of stinging insects. For more information, see the topic Allergies to Insect Stings. Allergies to animals , which are more likely to cause breathing problems than skin problems.
You may be allergic to your pet's dead skin dander , urine, dried saliva, or hair. Allergies to natural rubber latex. Some people develop allergic reactions after repeated contact with latex, especially latex gloves. Allergies that develop from exposure to a particular inhaled substance in the workplace.
These are called occupational asthma. Allergies to cosmetics, such as artificial nails, hair extensions, and henna tattoos. Health Tools Health Tools help you make wise health decisions or take action to improve your health. Decision Points focus on key medical care decisions that are important to many health problems. Actionsets are designed to help people take an active role in managing a health condition.
Check Your Symptoms Are you concerned about an allergic reaction? How old are you? Less than 12 years. Are you male or female? Why do we ask this question? The medical assessment of symptoms is based on the body parts you have. If you are transgender or non-binary, choose the sex that matches the body parts such as ovaries, testes, prostate, breasts, penis, or vagina you now have in the area where you are having symptoms. If you have some organs of both sexes, you may need to go through this triage tool twice once as "male" and once as "female".
This will make sure that the tool asks the right questions for you. Could you be having a severe allergic reaction? This is more likely if you have had a bad reaction to something in the past. Do you have symptoms of shock? The symptoms in an adult or older child are different than the symptoms in a young child.
Have you ever had a severe allergic reaction? Having an allergy can be a nuisance and affect your everyday activities, but most allergic reactions are mild and can be largely kept under control. Most of these allergens are generally harmless to people who are not allergic to them. Allergic reactions usually happen quickly within a few minutes of exposure to an allergen. Most allergic reactions are mild, but occasionally a severe reaction called anaphylaxis or anaphylactic shock can occur.
See a GP if you think you or your child might have had an allergic reaction to something. The symptoms of an allergic reaction can also be caused by other conditions. If they think you might have a mild allergy, they can offer advice and treatment to help manage the condition. If your allergy is particularly severe or it's not clear what you're allergic to, they may refer you to an allergy specialist for testing and advice about treatment.
Find out more about allergy testing. In many cases, the most effective way of managing an allergy is to avoid the allergen that causes the reaction whenever possible. For example, if you have a food allergy, you should check a food's ingredients list for allergens before eating it.
There are also several medicines available to help control symptoms of allergic reactions, including:. For some people with very severe allergies, a treatment called immunotherapy may be recommended.
This involves being exposed to the allergen in a controlled way over a number of years so your body gets used to it and does not react to it so severely. Allergies occur when the body's immune system reacts to a particular substance as though it's harmful.
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