What are hives?
Also known as urticaria (pronounced as ur-ti-kar-ee-uh), hives are characterised as clusters of swollen, raised welts (often smooth) on the surface of the skin which are pink, red or flesh-coloured and blanched (pale) in the centre.
Often these bumps (cysts, wheals or nettle rash) are itchy, and can be painful, causing a burning or stinging sensation. Physical sensations range from mild to severe. Hives can appear suddenly, sometimes for no distinctive reason, and vary in size (small spots to larger markings or blotches) and shape. A bout of hives can occur in anyone of any age and at any stage.
Hives are mostly classified as an acute condition (i.e. temporary) and are most often triggered by an allergen (foodstuff, medication or environmental irritant). Hives can, however, occur on a frequent basis and become a chronic condition. Chronic hives are generally accompanied by severe allergic reactions which can have serious complications. They are thus not considered a contagious condition.
Hives can occur anywhere on the body and can sometimes join together to form larger inflamed welts, known as a plaque. Hives typically flare-up quickly and can remain for several hours to a day (24 hours) or so at a time before fading. Hives do appear to have a tendency to rapidly change in size once a flare-up occurs, and ‘move around’ (i.e. they can disappear from one location of the body, and flare-up in other portions of the body, sometimes in a matter of hours).
Hives are one of the few skin conditions which occur and then appear to resolve in such a short space of time. This can make for difficult diagnosis if severe enough that medical treatment is sought out. It is advisable to photograph the markings while at their worst for a doctor to analyse, should medical treatment be sought out.
What causes or triggers hives?
Most often, an allergic reaction causes an outbreak of hives. Once an allergen has been encountered (been made contact with) or swallowed (ingested), the body responds by releasing histamines into the bloodstream. Histamine is essentially an organic nitrogenous compound which affects immune responses (i.e. histamines are released as a defence mechanism against infection or what is determined to be an ‘intruder’ in the body) and influence the regulation of physiological function in the gut. Histamine also functions as a neurotransmitter (chemical messenger) for the spinal cord, uterus and brain.
In an allergic reaction, histamines can aggravate the body by leaking out of small blood vessels (capillaries) and into the skin, resulting in inflammation (swelling), itching and stinging sensations due to an accumulation of this fluid.
This reaction may be triggered by elements such as:
- Foodstuffs (or chemicals in certain foods, food colouring and preservatives) – fish, shellfish, eggs, milk, strawberries, wheat, tree nuts and peanuts
- Animal dander – dogs, cats or horses
- Dust mites
- Plants – poison ivy or poison oak, and nettles
- Medications (antibiotics and nonsteroidal anti-inflammatories / NSAIDS)– most common are those containing penicillin, aspirin, naproxen, ibuprofen and some blood pressure drugs (ACE / angiotensin-converting-enzyme inhibitors)
- Insect bites or stings
- Cockroaches and cockroach waste
- Chemicals – fragrances, cleaning detergents, shampoos, hair dyes, cosmetics and bath or shower products
- Sunlight exposure - solar urticaria
- Water (on the skin) - aquagenic urticaria
2. Other common triggers
Non-allergic triggers can include:
- Exercise and excessive sweating (resulting in body heat-inducing hives)
- Excessive exposure to hot or cold temperatures (air exposure) and high body temperature (cholinergic urticaria)
- Rubbing, scratching or friction with the skin (dermagraphism)
• Pressure due to constrictive clothing or in areas of the body under constant pressure (such as the soles of the feet)
- Stress (this is an emotional aggravator that has the potential to elicit a number of physical reactions in the body)
- A viral or bacterial infection – hepatitis, Epstein-Barr virus, HIV/AIDS, flu (influenza), and cytomegalovirus (belonging to the herpes family of viruses), urinary tract infection and strep throat
- Underlying medical conditions – lupus, lymphoma and thyroid disorders, as well as a response to blood transfusions and blood products
- Inflammation of the blood vessels (vasculitis) – these can be painful and itchy, as well as leave a bruise on the skin
- Intestinal parasites
Types of hives
1. Urticaria categories
There are various forms of hives which are closely linked with the inducing triggers, but typically fall into one of two main categories – acute and chronic.
- Acute urticaria: Also referred to as ‘ordinary hives’, this category of urticaria typically resolves spontaneously within 6 to 8 weeks. The most common underlying causes of hives are due to an allergic reaction. Some forms of acute hives can also occur with anaphylaxis (a severe, potentially life-threatening allergic reaction). An underlying internal condition or disease causing hives can also fall into the category of acute hives.
- Chronic urticaria: Chronic hives typically continue longer than 6 to 8 weeks, and occur almost daily, with recurring flare-ups ranging from months to years. It’s fairly unusual to be able to determine an exact cause of chronic hives (therefore the condition is termed idiopathic). Doctors may recommend laboratory or allergy testing when presented with signs of hives, but results do not always help to determine an underlying cause. Precise information relating to medical history, oral intake (foods, medications etc.) and personal habits can be helpful in pinpointing potential causes. If any of these clues create suspicion of potential hive inducing culprits, these triggers may be avoided for a period of time in order to observe a person and see whether there is a determinable cause. In some cases, a doctor may determine an underlying medical condition, such as a thyroid disorder, type of cancer, coeliac disease, rheumatoid arthritis, lupus, type 1 diabetes or infection which could have a role in flare-ups of hives. Chronic hives must be monitored and treated by a medical professional as symptoms can also affect internal organs (such as the gastrointestinal tract lungs and muscles of the body), as well as lead to the development of other problems like shortness of breath, muscle aches, diarrhoea or vomiting. Chronic causes may also be linked to immune system reactions or abnormalities.
Flare-ups can also fall into one of these sub-categories:
- Intermittent urticaria: Flare-ups may occur over a period of a few days or weeks, subside and recur at intervals of days, weeks or even months (i.e. hives flare-up and then resolve intermittently).
- Urticaria of known cause: Forms of hives for which a doctor can determine an exact cause include physical urticaria (triggered by physical stimuli such as pressure, friction, extreme temperatures, water or sunlight exposure), delayed pressure urticaria (chronic hives due to pressure stimuli), cold urticaria (hives as a reaction to cold temperature exposure), and cholinergic urticaria (hives as a reaction to profuse sweating).
2. Forms of urticaria (hives)
Some of the more common forms which can be either acute or chronic hive conditions include:
Sometime referred to as ‘giant hives’, angioedema causes swelling in deeper layers of the skin, mainly affecting the facial area, hands, feet and sometimes the genitals too. Deep swelling around the eyes (eyelids) and lips can be quite dramatic, and if affecting the tongue and throat can also impact breathing by blocking the airways. If this happens, angioedema can be life-threatening.
Angioedema symptoms include:
- Large, firm and thick welts appearing on the surface of the skin (mainly affecting the eyes, mouth, cheeks, throat, hands or feet)
- Redness (inflamed) and swollen affected areas (resembling discoloured patches and rash)
- Warm sensations, itchiness or pain in the affected areas
Swelling, although dramatic, may only occur briefly and can resolve within a 24-hour period. As a condition, angioedema is a related type of swelling to ‘ordinary hives’ and it most often looks a whole lot worse than it actually is. Hive-like markings and swelling typically don’t leave any long-term effects, even if left untreated. Swelling that becomes life-threatening is rare.
When severe, symptoms include:
- Hoarseness (voice)
- Stomach cramps
- Chemosis (severe swelling of the eyelids or lining of the eyes)
- Difficulties with breathing
The reaction is similar to that of acute hives, but merely affects deeper layers of the skin (ordinary hives affect the surface layers or epidermis). Both conditions can occur separately or simultaneously. Triggers and causes may be similar, and typically resolve with or without medical treatment.
There is a genetic link that has been noted whereby the condition can be passed from parent to child (genetic transmission). This is known as ‘hereditary angioedema’.
Direct physical stimuli which makes contact with the skin and resulting in hives is known as ‘physical urticaria’. Temperatures (cold or heat), pressure and vibration, exercise and excessive sweating, water and sun exposure are some examples of triggers causing physical hive reactions.
Hives typically occur directly on the portions of the body which were exposed to a physical stimulus, and very rarely develop on other areas that were not in direct contact with it. Hives generally develop within an hour following exposure.
Forms of physical stimuli hives include:
- Dermographism (’skin writing’): Skin scratches, pressure or rubbing can lead to this type of hive reaction (leakage of histamine), producing an exaggerated reaction that results in red, raised and itchy welts at the site of contact. Adjacent flare-ups can appear anywhere else too where contact such as with clothing (belts etc) rub against the skin. Although an exaggerated reaction, hives are normally mild and can clear on their own within a short period of time.
- Cholinergic urticaria: Clusters of small, itchy, red bumps (with redness around the markings as well) can occur within minutes (up to 15 minutes) of physical exertion, such as exercise (often accompanied by sweating), and often resolve just as quickly (or within a few hours). Raised body temperature can bring about an eruption of bumps within minutes of exercise and worsen during the course of the next half an hour. Areas of the body most prone to sweating first are normally where hives will occur (i.e. the neck or chest areas) and then spread to other portions. In severe instances, hives may also be accompanied by other symptoms such as nausea, vomiting, abdominal pain, hypersalivation and diarrhoea. Exercise-induced anaphylaxis (a form of exercise-induced allergic reaction) may also occur which will require immediate medical intervention. Symptoms of anaphylaxis include breathing difficulty, wheezing, and headache.
- Solar urticaria: Commonly referred to as a ‘sun allergy’, solar hives are a rare allergic reaction and sensitivity to sunlight exposure (sunlight stimulates histamine in the body). A reaction typically occurs within minutes of exposure and can last for just a few minutes or up to several hours at a time. Solar hives can fall into either the acute or chronic category. The cause of this reaction is largely unknown, but in either category, is treatable. In some cases, it is believed that certain wavelengths of UV light may trigger reactions. Welts may itch, burn or sting and also be accompanied by symptoms of headache, nausea, low blood pressure and breathing difficulties. Sometimes hives can form blisters and become crusty too. Flare-ups can occur not only on bare skin exposure, but also on portions of the body covered with thin fabrics. Hives do tend to clear and don’t typically leave markings or scars.
How to recognise the signs and symptoms
What do hives look and feel like?
Welts or wheals can be small or large, ring-shaped (or roughly oval), and even take on more random blotchy or worm-like shapes. Hives can also resemble insect bites, such as those from a mosquito. Hives may be red and inflamed (or with a red flare / halo), but can also appear as smooth raised, flesh-coloured bumps or markings. If pressed, markings may pale and turn white (become ‘blanched’). Hives may grow larger (or merge together and create larger patches), occur in batches or clusters, spread to other portions of the body or change in shape too.
Flare-ups can itch, burn or sting (ranging from mild to intense), swell, disappear and reappear (forming new markings where previous ones have faded) within a short space of time or as a reaction runs its course. Flare-ups can happen multiple times in a day, or alternatively during the course of weeks or months.
Hives can affect any and every portion of the body, but are more common on the facial area, neck, arms, fingers, hands, legs, toes and feet.
Chronic hives can be a little more troublesome and affect a person’s normal habits, such as daily activities or ability to sleep comfortably. Swelling of the lips, eyelids (which may be swollen shut), tongue and throat (angioedema) can be quite painful often causing a burning sensation (this is not normally itchy), and not always symmetrical.
How to tell the difference between hives and psoriasis
Some characteristics of both hives and psoriasis are similar, but the two conditions are not the same. Psoriasis is classified as an autoimmune skin condition whereby cells rapidly accumulate to form thick skin lesions and plaques (scales). As an immune-related condition, psoriasis is also not a contagious disease, and is mostly triggered by things such as stress, injury to the skin, infections (such as strep throat), foodstuffs (like red meat or dairy products), certain medications (such as those containing lithium or some high blood pressure drugs) or extreme cold weather conditions.
Mild or severe outbreaks result in inflamed or red scaly lesions, and skin that is dry and or / cracked can sometimes bleed. Skin may also itch, burn or become painful. Nails may also thicken, ridge or become pitted. Affected skin areas may also affect the joints, causing swelling and stiffness.
So, what are the differences?
- Hives: Bumps are raised and smooth, appear suddenly, come and go (disappear and reappear) and seldom rupture and bleed (unless itching is extreme).
- Psoriasis: Bumps are usually scaly and have a silvery coating, appear gradually, linger for weeks or months at a time, and often bleed.
A person may be more prone to hives if they have existing food allergies, are under a fair amount of stress or have sensitive skin. Those who experience flare-ups of psoriasis generally have a family history of the condition, experience chronic levels of intense stress, smoke, are overweight or who generally have a weak or compromised immune system.
What are the risk factors for hives?
Risk of hives, either acute or chronic, increases due to any of the following:
- Allergies (existing or newly developed)
- A personal history of hives
- A family history of hives (especially in the case of hereditary angioedema, although rare)
- A known disorder that is associated with hives (infections such as urinary tract infection, strep throat, hepatitis, rheumatoid arthritis, or type 1 diabetes)
- Frequent viral infections
- Medications (allergic and non-allergic mechanisms, including codeine, aspirin, morphine, and NSAIDs)
- Existing skin sensitivities or dermatitis (inflammation of the skin)
- Existing sensitivities to disinfectants, dyes, chemicals, or perfume fragrances
- Emotional triggers (association with stress and anxiety)
When to worry and consult a doctor
In general, most instances of acute or chronic hives are mild and non-threatening, with flare-ups resolving themselves. When a hive outbreak affects the tongue or throat, breathing difficulties can occur.
Serious allergic reactions such as anaphylaxis can affect the entire body (causing breathing difficulty, difficulty swallowing, severe swelling of the tongue, lips, mouth lining, eyelids, throat, and dizziness) and must be attended to by a medical professional urgently. Swelling can quickly affect the airways, causing a loss of consciousness if not attended to quickly enough. Anaphylaxis is considered a medical emergency and can be life-threatening.
If symptoms of hives are severe or continue for several days, it is best to consult a doctor for a diagnosis and treatment plan.
It is best to seek medical treatment as soon as possible if any other symptoms develop, such as:
- Nausea and vomiting
- Abdominal pain
- Respiratory stridor (noisy or strained breathing) and wheezing
- Rapid or irregular heartbeat
- Body weakness
- Light-headedness or fainting (loss of consciousness)
- Cold and clammy skin
- A sudden feeling of intense anxiety
- Tightness in the chest
- Trouble sleeping
- Low blood pressure and shock
Which medial practitioner is the best to see?
- Family physicians / general practitioners (GP)
- Paediatricians (if a child develops hives)
How are hives diagnosed?
In general, there are no specific tests available for the diagnosis of hives. This is due to the nature of triggers, which in many instances is non-specific or idiopathic. In some cases, a trigger can be identified – for instance a type of medication. Discontinuation of the medication can determine whether it is a trigger if an outbreak of hives clears once being discontinued. If it does not, the medication is not likely the cause.
In order to try and determine an underlying cause of hives, such as an allergic reaction, a doctor will wish to obtain a detailed medical history and conduct a symptom discussion during the consultation, followed by a thorough physical examination.
Questions a doctor may ask during the consultation include:
- How long ago did symptoms first begin?
- How did the markings on the skin look when they first appeared?
- Have the markings changed in way (such as size or shape) since?
- Has anything appeared to make symptoms better or worse before this consultation?
- Are the skin markings itchy, burning or stinging at all?
- Have any markings disappeared without leaving another marking such as a bruise before this consultation?
- Have any allergies been diagnosed? If so, what?
- Has a similar skin problem ever developed or occurred in the past?
- Have any new foods been eaten for the first time?
- Have any new products, such as cleaning detergents been introduced for the first time?
- Have any insect bites or stings occurred recently?
- Are any new medications (prescription or over-the-counter) currently being taken (including herbal supplements)?
- Has a new pet been introduced into the home?
- Has a family member ever had a similar type of skin problem?
- Do any family members have any known allergies?
- Have there been any other noted health changes recently? (i.e. a fever or a little unintended weight loss)
- Have any a-home treatments been applied at all? Have they improved or worsened symptoms?
A doctor will then conduct a physical exam and evaluate the skin markings (those that are present). If allergies are suspected, a skin prick test may be performed to determine the substance causing the reaction. It may be that a trigger is fairly obvious to pinpoint, such as a reaction occurring in a short space of time following the ingestion of shellfish or peanuts, or exposure to sunlight or water, after a scratch has occurred to the skin or following strenuous exercise.
Once a trigger allergen is determined, a doctor will advise against contact with or ingesting a particular foodstuff, or other products made from or containing the substance. If deemed safe enough to do, an oral food test may be requested where a suspected allergen will be given to the affected individual to eat (in a measured amount) to induce a hive reaction. The same type of oral test can be done with medications as well (a cautious drug challenge). If the risk of severe reactions, such as anaphylaxis is too high, these tests may not be performed, but any that are will be carefully monitored for their duration, often with emergency equipment or medication on hand.
Blood tests may also be recommended to assess for particular illnesses known to be associated with hive outbreaks, as well as to check blood proteins if there is a potential hereditary pattern (as in the case of hereditary angioedema). A urine sample can also sometimes be recommended.
Extensive testing is not normally favoured by medical professionals in the case of mild hive outbreaks or a single occurrence having taken place. Chronic hives are not commonly linked with an allergic reaction (due to the frequency of recurrences – often for more than 6 weeks). It is more likely that a cause is not external in nature. Relevant tests will be done to determine an underlying cause which can be an autoimmune disease or other medical disorder.
Tests which may be recommended (where relevant) in the case of chronic hives may include:
- Blood tests (to check for signs of anaemia)
- Thyroid function test (to assess any signs of an overactive or underactive thyroid – hyperthyroidism or hypothyroidism)
- Liver function tests
- ESR (erythrocyte sedimentation rate) test (to assess any immune system abnormalities)
- Stool (faeces) sample (to assess for or identify any parasites causing an infection)
Tests for angioedema may include:
- Blood tests: C1 esterase inhibitor test (this test checks complement protein levels and helps to determine any underlying reasons for swelling) and complement components (C2 and C4) to assess for any deficiencies. Low levels of these components can show signs associated with swelling and inflammation in the body.
In the case of solar hives (urticaria), tests may be recommended in order to make a diagnosis. These can include:
- Photo-testing: A doctor or allergist may assess skin reactions when exposed to UV light from a sun lamp, using a variety of different wavelengths. The wavelength that the skin reacts to will be used to determine the nature of the sun allergy.
- Patch testing: Certain substances (a suspected sensitizer agent which may trigger a reaction) is applied to the skin and covered with a patch or dressing for a period of time (about 24 to 48 hours). The area will then be evaluated to assess a potential reaction. Skin may then be exposed to UV light (radiation) from a sun lamp. If skin reacts, a diagnosis for solar hives can be made.
- Blood tests: Autoimmune or metabolic clues in symptoms may be tested for with blood samples (and sometimes skin biopsies) to try and determine an underlying cause.
Tests for cholinergic hives may include:
- An exercise challenge test: A doctor will request the patient to perform an exercise routine in order to attempt to stimulate a similar reaction. Medical instruments may also be used to take various measurements during the challenge.
- A passive warming test: A doctor will use warm water or increased room temperature to raise the patient’s internal body heat temperature and observe a possible reaction during the exposure test.
- A methacholine skin challenge test: A non-selective muscarinic receptor, methacholine will be injected in order to stimulate the parasympathetic nervous system and observe a potential reaction.
What is the treatment for hives?
A mild case of hives may not necessarily require prescription treatment, unless related to an allergy or other underlying medical condition. For the most part, treatment can help to alleviate symptoms (itching and burning or stinging sensations) causing discomfort, and reduce the likelihood of flare-ups.
Treatment is essentially aimed at alleviating the discomfort of symptoms while the welts and markings heal.
For mild outbreaks of hives, a doctor may recommend the following:
- Taking antihistamines / H-2 blockers (to block leakage of histamine and alleviate symptoms of itching and swelling, as well as prevent the formation of new outbreaks or flare-ups)
- Prescription anti-inflammatory medications (oral corticosteroids can help to reduce itching, redness and swelling by suppressing an allergic reaction, or for severe cases of hives or angioedema offer short-term treatment)
- Prescribed immune system suppressant medications (for the relief of an overactive immune system or where antihistamines and anti-inflammatory medications are proving ineffective)
- Avoiding hot water on the skin and direct sunlight (this can sometimes aggravate an outbreak of hives)
- Bathing in cool or lukewarm water with added colloidal oatmeal (finely ground oatmeal)
- Avoiding any irritants to the affected skin areas (such as clothing)
- Avoiding scratching the affected skin areas
- Avoiding exercise, caffeine, alcoholic beverages and emotional stress which can worsen symptoms
For chronic hives, a doctor may:
- Recommend antihistamines
- Prescribe corticosteroid medications (oral) or non-steroidal anti-inflammatories
- Prescribe antibiotics to treat swelling and inflammation
- Prescribe an EpiPen (epinephrine autoinjector) to self-inject epinephrine during severe or chronic flare-ups (this must be kept on hand at all times to alleviate early signs of anaphylaxis quickly)
- If a cause of chronic hives is determined as idiopathic, a doctor may request that an affected person keep a journal for a period of time to track activities, foods and drinks ingested, medication or supplement use (if applicable), and general habits. These can be compared with any hive flare-ups, the nature of which can also be noted in the journal (when hives appeared, how long they lingered for, and the nature of other symptoms, such as sensation severity etc.). Sometimes a trigger may not be an underlying cause of hives, but can be determined as an aggravator. A diary / journal can help a doctor to determine the differences.
For severe hives and angioedema, a doctor may:
- Administer an injection of adrenaline (epinephrine) – often used in an emergency situation
- Prescribe cortisone medication
- Prescribe blood protein controller medications to help with regulation and alleviate symptoms
- Prescribe an EpiPen should an emergency situation or severe flare-up occur
- Give the patient intravenous (IV) fluids to increase blood pressure (this is normally a saline solution)
- In an emergency situation where breathing is difficult, oxygen may be given via a face mask or through a breathing tube (inserted through the nose)
Any severe case which has resulted in a hospitalisation will require the patient to be monitored for some time, as recurrence risk is fairly high.
Solar hives (urticaria) often resolves on its own, but can be treated with:
- Medications such as corticosteroids and some used to treat asthma or hydroxychloroquine (an antimalarial drug)
- Phototherapy (this helps to ‘prepare the skin’ for sunlight exposure by administering low doses of sunlamp ultraviolet radiation to desensitise the body to its effects – results may not be long-term, however)
- Immunosuppressants, plasma exchange (separation and removal of plasma – white and red blood cells and platelets - in the blood, which are then returned to the system), photopheresis (a form of photodynamic therapy and apheresis which treats blood with a photosensitising agent, and this is then irradiated with light wavelengths) and intravenous immunoglobulin (can help with raising low red blood cell counts)
Cholinergic hives can be treated:
- With lifestyle modifications (especially relating to physical and strenuous exercise activity which may need to be modified so as not to elevate body temperature too much – e.g. limited outdoor exercise activities during warmer months of the year)
- By managing anxiety and stress-related triggers (if applicable)
- Through the administration of medications that may be recommended or prescribed to alleviate symptoms (such as antihistamines / H1 antagonists) or manage the amount of perspiration produced by the body (methantheline bromide), beta blockers, immunosuppressants or those used to treat UV light exposure.
- With an EpiPen, if severe symptoms are a risk for exercise-induced anaphylaxis complications
Before taking any prescription or over-the-counter medications, it is advisable to discuss all known side-effects with a doctor to ensure optimum comfort while taking the drugs. Antihistamines are known to cause a little drowsiness (often a reason why they are taken at night before bed), dry mouth, dizziness, nausea, vomiting, concentration problems and trouble with urination. They are generally long-lasting and provide some of the most effective relief of hive symptoms as welts heal.
Some medications may not be recommended or prescribed for women who are pregnant or breastfeeding. Symptoms will be assessed and alternative home care treatments, or medications deemed safe, may be recommended instead. If a chronic medical health condition is already under treatment or other medications are currently being taken, a doctor will assess benefits over risks, and potential drug interactions before recommending any medicinal treatment, so as to avoid adverse effects.
Side-effects of corticosteroid medications can include swelling, elevated blood pressure, elevated eye pressure, weight gain, cataracts, elevated blood sugar levels and reduced hormone release from the adrenal glands. This is often why long-term use, particularly for severe or chronic hives is not typically recommended (lower doses or supervised transition to creams are sometimes prescribed instead).
Other medications which may be recommended when antihistamines are not effective include:
- Injectable man-made monoclonal antibodies (for difficult-to-treat hives which occur on a chronic basis)
- Some asthma medications (leukotriene modifiers) used along with antihistamines
Topical creams and lotions may be recommended to help numb nerve endings and in this way, alleviate itching or stinging sensations. Many topical ointments, however, are not very effective and especially for those with heightened sensitivity. Camphor, aloe Vera, calamine, pramoxine, diphenhydramine and menthol are some lotion containing substances which can provide some relief.
A skin patch test may be done before any topical creams or lotions (even those containing natural compounds and ingredients) are applied as contact dermatitis can occur. Cortisone-containing lotions (which are normally prescribed) are not terribly effective either, even if quite strong. Sometimes a tricyclic antidepressant (in cream form), which has a strong antihistamine effect, may be prescribed for some topical relief from itching but may cause a little drowsiness or dizziness as side-effects.
If an EpiPen is used, a person must visit the emergency room as soon as possible following use for a thorough check-up by medical professionals.
Home care – Managing an outbreak of hives
The following may help to alleviate mild symptoms:
- Use cool compresses, moist dressings or bandages and damp cloths, applied to affected skin to help soothe and prevent the urge to scratch (scratching the itching markings should be avoided as this can worsen an outbreak)
- Maintain a cool temperature in the home (during the day and at night), or if cold temperatures are a trigger, a mild temperature that does not aggravate symptoms
- Wear lightweight and loose-fitting clothing (i.e. soft cotton fabrics instead of wool which can scratch the skin)
- Avoid allergens and triggers
- Take frequent cool / lukewarm (or tepid) baths (as needed), with a sprinkling of uncooked oatmeal or colloidal oatmeal (this helps to alleviate itching)
- Avoid using harsh soaps while bathing (try gentle soaps made for sensitive skin instead)
- Apply a sunscreen (approved by a treating doctor) when heading outdoors
- Avoid smoking or consuming alcohol, especially while taking medications (this can aggravate and worsen symptoms)
Is a follow-up appointment necessary?
No, not always. Mild to moderate hive outbreaks normally resolve without complications or long-term effects. If any recurring or new symptoms develop, however, a medical professional should be consulted.
Some signs needing medical evaluation include:
- A new or recurring rash (especially if it is worse than before)
- Severe side-effects from medication use
- Swelling or sores on the tongue, in the mouth or throat
- Fever (or chills)
- Difficulties with swallowing and or / breathing
Can hives be prevented?
Making lifestyle adjustments that limit or avoid hive flare-up triggers are most often the best way to reduce the likelihood of an outbreak or recurrences. It is not always possible to completely prevent a hive outbreak experience.
A diagnosed allergy (or known cause such as medications, environmental factors, foods or exposure to certain pets) is one-way triggers can be easily avoided. Treatment for specific allergies can also help to reduce risk and alleviate outbreaks.
If a cause is not entirely known, and frequent flare-ups occur, keeping a journal or diary which draws parallels between ‘cause and effect’ (e.g. food consumed and a possible reaction) may help to identify and thereby avoid potential triggers.
For solar hives, protective measures can include:
- Careful management of sun exposure (refraining from being out in the sun when at its strongest – often between 10 am and 4 pm, and gradually increasing time outdoors during the in-between months – spring and autumn or fall – to try and better adapt to stronger sunlight exposure).
- Wearing lightweight or closely woven clothing which provides maximum coverage (long pants or skirts and sleeved garments).
- Wearing clothing which has a UPF (ultraviolet) protection factor of at least 40, as well as a sunscreen (broad-spectrum) approved by a treating medical professional (and applied regularly).
- Making use of anti-sun aids such as sunglasses, hats with a broad brim and umbrellas.
Outlook for hives
More often than not, an outbreak of hives is not a serious condition, although an occurrence is understandably uncomfortable. Generally, an outbreak is harmless, resolving itself and very rarely becomes a life-threatening reaction. Severe reactions can quickly become dangerous and if not effectively treated can be life-threatening for the person concerned.
Hives can be both predictable (triggered by a known cause) and not, often disappearing and then popping up again. Most cases of hives can be effectively controlled and do not typically leave any long-term damage or adverse effects following an outbreak.
What other conditions may mimic hives?
There are known skin problems that can be mistaken for hives. Some of these can include:
- Heat rash: When skin is exposed to very hot and often, humid weather conditions, sweat ducts can become blocked, forming fluid-filled blisters and bumps (accumulation of sweat, particularly in the folds of skin – in the groin, beneath the breasts, in the armpits or the inner thighs). These can be very sensitive to the touch and itchy. Friction caused by certain types of clothing can also aggravate these bumps, which range from mild to severe. Severe heat rash may result in bumps which affect the deeper layers of skin and fill with pus instead of a clear fluid. Heat rash can, however, also clear on its own once the trigger has been removed or if treated by cooling the skin down, reducing sweating, and restoring a normal internal body temperature.
- Contact dermatitis: A red rash develops following aggravating contact with the skin, such as an allergen substance. This could be an ingredient in a cream or make-up product, or metal found in jewellery, or detergent or soap. The sensation which occurs with contact dermatitis is usually more stinging or burning than an itch. A rash typically only occurs where contact with a trigger was made.
- Eczema: Red, inflamed, scaly, dry and itching skin are typical of an eczema breakout. Eczema can easily be confused with the physical characteristics of hives, as well as occur anywhere on the body. Exact causes of eczema are sometimes difficult to pinpoint, as is often the case with chronic hives. This skin condition, however, is often linked with an overactive immune system. Making an appointment with a dermatologist is best to diagnose eczema and treat it accordingly. Many treatments for hives will not be effective for an eczema breakout.
- Rosacea: This condition normally occurs on the facial area more than anywhere else on the body. A typical characteristic of rosacea is reddening of the cheeks, forehead, nose and chin. The condition also produces small pimple-like bumps and blood vessels, as well as watery eyes. Medications are the best course of treatment for this type of skin condition.
- Pityriasis rosea: A splotchy red rash can sometimes last for between 6 and 8 weeks (like a case of chronic hives) but can resolve on its own without any treatment at all.
A clue that a rash or marking may not be a case of mild or acute hives could be that it does not resolve within a 24-hour period. Another is if welts are filled with clear fluid, they are more likely hives.
Markings or bumps that are hard or filled with other materials, such as pus or are brownish in colour are often indicative of a more serious skin condition which will require medical diagnosis.