What is the cause of hives allergy
Hives are frequently associated with allergic and autoimmune reactions. The rash forms when blood plasma leaks out of little blood vessels in response to histamine. Common triggers for histamine release, and subsequently the hives, include: some foods, medications, insect stings or bites, physical stimuli love pressure, freezing or heat, latex, bacterial and viral infections, pet dander and pollen. Acute hives come on suddenly and typically final between 24 to 48 hours
Main allergy symptoms
Common symptoms of an allergic reaction include:
- tummy pain, feeling ill, vomiting or diarrhoea
- a raised, itchy, red rash (hives)
- itchy, red, watering eyes (conjunctivitis)
- wheezing, chest tightness, shortness of breath and a cough
- sneezing and an itchy, runny or blocked nose (allergic rhinitis)
- swollen lips, tongue, eyes or face
- dry, red and cracked skin
The symptoms vary depending on what you’re allergic to and how you come into contact with it.
For example, you may have a runny nose if exposed to pollen, develop a rash if you own a skin allergy, or feel sick if you eat something you’re allergic to.
See your GP if you or your kid might own had an allergic reaction to something. They can assist determine whether the symptoms are caused by an allergy or another condition.
Read more about diagnosing allergies.
How endless will an outbreak last?
There are two forms of hives, acute and chronic, or short term or endless term. Symptoms can final anywhere from a few minutes to weeks or months. Hives can appear anywhere on the body, they can come and go over a period of time.
Hives are not generally dangerous, however, any swelling of the throat or restricted breathing does require immediate attention and emergency care.
Symptoms of an allergic reaction usually develop within a few minutes of being exposed to something you’re allergic to, although occasionally they can develop gradually over a few hours.
Although allergic reactions can be a nuisance and hamper your normal activities, most are mild.
Very occasionally, a severe reaction called anaphylaxis can occur.
Severe allergic reaction (anaphylaxis)
In rare cases, an allergy can lead to a severe allergic reaction, called anaphylaxis or anaphylactic shock, which can be life threatening.
This affects the whole body and usually develops within minutes of exposure to something you’re allergic to.
Signs of anaphylaxis include any of the symptoms above, as well as:
Anaphylaxis is a medical emergency that requires immediate treatment.
Read more about anaphylaxis for information about what to do if it occurs.
Sheet final reviewed: 22 November
Next review due: 22 November
Senokot S Side Effects
Generic Name:docusate / senna
Note: This document contains side effect information about docusate / senna. Some of the dosage forms listed on this sheet may not apply to the brand name Senokot S.
What treatment is available?
Mild outbreaks can be relieved with a variety of at home treatments including:
- Calamine lotion
- Cold compresses or baths
- Antihistamines in pill or ointment form
More severe outbreaks may require medical attention from the doctor.
The doctor may prescribe one of the following:
- A short course of steroids
- Antileukotriene medicines
If a patient experiences restricted breathing due to swelling in the tongue, throat or lips, a doctor may prescribe an epinephrine pen in case of an emergency, as they symptoms are early indicators of anaphylaxis. As with most allergic reactions the best course of management is avoidance. The doctor will order additional testing if necessary and may develop a endless term treatment plan.
What are hives?
Hives, which can also be called by its Latin name Urticaria, is a condition where itchy, raised red bumps which can appear anywhere on the skin. The bumps resemble blisters and are called wheals. The wheals are accompanied by redness in the skin and an itching or burning sensation. They vary in size, but are typically little, about the size and shape of a pencil eraser.
So, Youve Been Diagnosed with Hives!
by Richard S.
So, if acute hives don’t seem to own an allergic cause what else could be going on? One of the more common presumed causes, especially in children is post-infectious hives. During or within a week of viral, strep or other infections hives may happen through poorly understood mechanisms. This often leads to confusion when antibiotics own been given for the infection. Were the hives from the antibiotic or from the underlying illness? Post-infectious hives can recur for up to 6 weeks. At times, even without infection or any obvious trigger a few hours to a few days of hives happen. These are called acute idiopathic hives.
We assume that the immune system is inappropriately activating the skin mast cells but we don’t know why. We don’t ponder that stress is a common cause.
So, your hives own gone on for more than 6 weeks, so they drop into the chronic urticaria category. Now what? Once again you’re not alone. Approximately 3 million Americans of every ages own the same problem. There are some significant things that you should know. The first is that, unlike acute urticaria, less than 5% of the cases are due to some external cause.
Also, unlike acute urticaria, the hives and /or swelling are rarely dangerous. In this form of hive problem various quirks and idiosyncrasies of the immune system, as they relate to mast cells, are the primary cause.
Our understanding of the problem is improving but there are numerous unanswered questions. The best understood of these idiosyncrasies is called chronic autoimmune urticaria. Approximately 45% of every chronic hives are of this type. In this condition the immune system makes a detectable antibody (for which we own a test) that mistakenly thinks that parts of the mast cell surface are the enemy. This antibody attacks the skin mast cells which leads to the release of histamine, etc.
It’s been known for a endless time that if our body makes one autoantibody type of error it’s easier for it to make other autoantibody mistakes. Therefore, it’s not terribly surprising that in chronic autoimmune urticaria approximately 20% of patients, especially women, will also own autoantibodies that target the thyroid gland. This may lead to Hashimoto’s thyroiditis and periodically blood tests for thyroid function should be checked. Unfortunately, treating this thyroid condition probably does not benefit the hives.
The next most common type of chronic urticaria is chronic idiopathic urticaria. This condition is almost certainly due to the immune system’s interaction with mast cells but the details are unknown.
Both chronic autoimmune and chronic idiopathic urticaria may worsen during febrile illnesses, with the use of aspirin family medicines, prior to the monthly menstrual period or with sustained pressure to or rubbing of the skin. Individual hives that sting more than itch, leave bruises and final 3 or more days may indicate hives due to vasculitis (inflammation of the blood vessels).
Other forms of chronic hives own to do with the immune system’s reaction to physical triggers.
Hives produced by stroking of the skin is called dermographism. Some people’s hives are triggered just by freezing, heat, skin pressure, vibration, exercise, sun or even water. These conditions are fairly rare. Some exercise induced patients can either react just to exercise while others react only if their exercise follows the consumption of a food to which they are mildly allergic, most commonly wheat, celery and shellfish.
These exercise reactions can produce anaphylaxis and may be dangerous. Another dangerous condition, this one involving angioedema and never hives, is called hereditary angioedema. In these patients swelling of the upper airway can be fatal. Such patients also generally own pronounced abdominal pain from swelling of their intestines. Treatment is available.
So, now that you’ve put your hives into a category how are they treated? For acute hives and rare cases of chronic hives avoidance of triggers is the key.
If the acute hives are already present antihistamines and if severe, a short course of oral steroid is used. For chronic hives daily preventative antihistamines are essential. Doses higher than those used for nasal allergy treatment are often needed. If maximum antihistamine dosing has been reached without control, addition of an H2 blocker (e.g. Tagamet) and/or a leukotriene blocker (e.g. Singulair) may be tried. Maximizing the above therapy should minimize the need for oral steroid. Relying on recurrent courses of oral steroids (prednisone) especially without full antihistamine, H2 blocker and anti-leukotriene support is to be discouraged.
In rare cases cyclosporin or other immunomodulatory medicines may be added. Once control has been achieved medicines should be continued for several weeks or longer past the final symptoms. Slow tapering can then be attempted.
So, why are my mast cells releasing histamine and other things when they shouldn’t? The first question that needs to be asked is for how endless own you had hives? Hives that own been present intermittently or daily for less than 6 weeks are called acute hives, and if longer, chronic hives. Amongst the numerous possible causes of acute hives those due to allergic reactions get the most attention.
In allergic patients the mast cells are coated with an allergy antibody, called IgE, that recognizes a extremely specific target (peanut, penicillin, yellow jacket, etc.). When that substance, such as peanut, becomes attached to that allergy antibody a chain reaction occurs that activates the mast cell which results in the release of histamine and other inflammatory substances. A hive is born! For food allergy reactions, there are 3 useful rules to consider:
- Second, it goes away within a few hours or at the most within a day or two. Therefore, you never get hives for a week from one serving of peanut butter.
- First, the reaction begins quickly, within minutes of eating the food; on rare occasions up to an hour but almost never longer.
- Third, the reaction is reproducible, meaning that if hives were caused by eating 4 peanuts on a Monday, eating 4 peanuts the following week will almost always cause the same problem.
Despite favorite belief, artificial food colorings and food additives almost NEVER cause hives.
Hives from antibiotics is a diverse situation.
The hive reaction can start anywhere from a few minutes after the first dose to 10 days after finishing the course. Antibiotic related hives can persist for up to approximately 2 weeks.
Allergic hives from stinging insects are generally obvious but occasionally they can be sneaky by occurring while you’re asleep or distracted. They start quickly after the sting and resolve in a few hours to a few days. In the U.S. spiders, flies and mosquitoes almost never cause hives although rare cases own been reported.
Almost any medicine or herbal product can potentially cause hives but one of the most common medicines implicated is the aspirin family (aspirin, ibuprofen, naproxen, etc.).
Isolated swelling without hives is a unique side effect of the ACE inhibitor blood pressure medicines. Soaps, detergents, fabric softeners almost never cause hives but if they do, the hives happen only where the skin is touched. Airborne allergy to pollen, dust, etc. almost never causes hives unless the person is in the midst of a massive hay fever attack. In an allergic person, direct skin contact with a potent allergic substance love animal saliva or latex can cause hives at the site.
Every categories of allergic hives are potentially dangerous while chronic hives are generally not.
Do you really own the Hives?
Don’t despair. You’re not alone. Approximately 20% of the population will own hives (urticaria) at one time or another during their lifetime. First off, are you certain that they’re really hives? True hives are red, itchy, generally raised lesions that look very much love mosquito bites.
They are often circular or oval but can be irregularly shaped. Their size may vary from ¼ inch to several inches in diameter. They may blend together. Each spot lasts anywhere from hours and is surrounded by normal looking skin. As they resolve the skin looks normal, not flaky or rough. While the hives are present one spot will be resolving while another nearby is developing. In about 40% of cases localized swelling (angioedema) of the lips, eyelids, hands, feet or tongue also occurs.
So, if these are really hives they must be from an allergy, right? Well, unfortunately it’s not that simple and modern science doesn’t own every of the answers.
The history of how they first appeared and what’s happened to them since can provide significant clues as to what category of hives you own. But first, what actually is a hive? Everyone’s skin is made up of numerous types of cells. One of these cells is called a mast cell. Everyone’s mast cells make and store histamine. They also routinely make leukotrienes and other substances that can cause localized inflammation. Mast cells don’t generally release much of these substances into the surrounding skin but if they do, these substances, especially histamine produce localized redness, itch and swelling we recognize as a hive or if it’s slightly deeper, angioedema.
So, what’s my prognosis Doc?
As noted above:
- Less than 30% of idiopathic acute hives will go on to be chronic.
- Acute hives resolve spontaneously.
- If you own chronic hives that aren’t of the “physical” type at least 50% will resolve in less than a year and another 20% will resolve over the next several years.
The “physical” hives tend to be more endless lasting.
Research is ongoing in every of these areas. So hold your chin up, take your antihistamine, and get the necessary attention to the type of hives that you have.