The Allergic Response
Allergic responses have two phases: the acute and the chronic, observed as Wheal and Flare. This generally occurs rapidly after allergen exposure (<1hour). It is caused by the degranulation of mast cells and the release of histamine and other mediators.... continue reading ›
The wheal is the raised area of skin. The flare is the red area of skin surrounding the wheal.... read more ›
There can be many causes, including exposure to an allergen, a physical trigger, such as pressure from tight clothing, or an underlying health condition. The medical name for hives is “urticaria.” People also call it welts, wheals, or nettle rash. Hives affects around 20% of people at some time in their lives.... continue reading ›
wheal-and-er·y·the·ma re·ac·tion. the characteristic immediate reaction observed in an allergy skin test; within 10-15 minutes after injection of antigen (allergen), an irregular, blanched, elevated wheal appears, surrounded by an area of erythema (flare).... continue reading ›
Swelling of the surface of the skin into red- or skin-colored welts (called wheals) with clearly defined edges. Wheals may get bigger, spread, and join together to form larger areas of flat, raised skin. Wheals often change shape, disappear, and reappear within minutes or hours.... see details ›
Levocetirizine administered as monotherapy or in combination with montelukast in arm A and monotherapy with desloratadine, as well as concomitant treatment with desloratadine and montelukast in arm B were the most effective treatment options of inhibiting the size of wheal and flare in SPT.... continue reading ›
Description. Venous flare reaction, a localized allergic response associated with the administration of an irritant, is one of the most common chemotherapy infusion–related reactions.... view details ›
Medical Definition of wheal
: a suddenly formed elevation of the skin surface: as. a : welt especially : a flat burning or itching eminence on the skin.... see details ›
The extent of the reaction on the patient's skin is assessed to give a positive or negative skin prick test result. If the diameter of the wheal is ≥ 3 mm more than the negative control, this is considered a positive result.... view details ›
a small, burning or itching swelling on the skin, as from a mosquito bite or from hives. a wale or welt.... read more ›
What are hives? Hives are an outbreak of swollen, pale red bumps that appear suddenly on the skin. These bumps are sometimes called wheals or welts, and they may be circular or irregular in shape and range in size from pin-size dots to large map-like patches.... see more ›
Histamine is released by the body during allergic reactions, such as those to pollen, food, latex and medications. Pruriceptive itch is due to an allergic reaction, inflammation, dryness or other skin damage. It is seen in atopic dermatitis (eczema), urticaria (hives), psoriasis, drug reactions, mites and dry skin.... see details ›
Allergy skin tests results are typically reported as positive or negative. If there is an immune reaction to a potential allergen, that is considered a positive result. If not, then the test result is negative, which may indicate the patient does not have an allergy to that substance.... see more ›
A skin reaction from allergic contact dermatitis will go away, but usually takes from 14 to 28 days.... view details ›
The rash can develop within minutes to hours of exposure, and it can last 2 to 4 weeks. Signs and symptoms of contact dermatitis vary widely and may include: An itchy rash. Leathery patches that are darker than usual (hyperpigmented), typically on brown or Black skin.... see details ›
There are many potential causes for sudden skin sensitivity, like exposure to allergens or contact dermatitis, chronic conditions like eczema, psoriasis, and rosacea, or acute trauma from excess sun exposure.... see more ›
Stress hives often look oval, round, or ring-like but also can take on irregular shapes. A classic symptom of hives is itchiness. You may feel a tingling or burning sensation as if you've been bitten by mosquitos. In addition, some welts may disappear only to be replaced by new ones within a few hours.... read more ›
Symptoms of a flare reaction include: Tenderness. Warmth. Redness along the vein or at the site of the injection.... read more ›
Symptoms of this reaction are redness and itching at the injection site. Irritant chemotherapy agents include: bleomycin, carboplatin, carmustine, cisplatin, dacarbazine, denileukin difitox, doxorubicin, doxorubicin liposome, etoposide, ifosfamide, streptozocin, teniposide, thiotepa, vinorelbine.... see details ›
It is usually noted by 48 hours and peaks at 7 to 10 days. Far from being a theoretical risk in the patient with widespread metastatic disease, tumor flare frequently results in exacerbation of cancer-related bone pain and can cause paraplegia resulting from spinal cord compression.... see details ›
(wheals or hives) is characterized by elevated lesions caused by localized edema. Wheals are pruritic and red. Wheals are a common manifestation of hypersensitivity to drugs, stings or bites, autoimmunity, and, less commonly, physical stimuli including temperature, pressure, and sunlight.... read more ›
When hives are due to an allergic reaction, it's often an allergy to:
- A food.
- Bug bite or sting.
- Pet dander.
A positive result means you reacted to a substance. Your provider will see a red, raised area called a wheal. Often, a positive result means the symptoms you're having are due to exposure to that substance. A stronger response means you are likely more sensitive to the substance.... view details ›
The author group is comprised of otolaryngologists and allergists. This group defined a positive prick test as “A wheal 3mm or larger than the negative control is considered positive.... read more ›
The risk with allergy blood tests is pain or bleeding where the needle enters the skin. Also, some people may feel dizzy or faint during blood testing.... view details ›
A wheal is a skin lesion caused by an allergic reaction. Hives are an example of wheals.... read more ›
Allergic reactions to food, insect bites, pollen, and medicines. Skin conditions such as eczema, psoriasis, and dry skin. Irritating chemicals, cosmetics, and other substances. Parasites such as pinworms, scabies, head and body lice.... view details ›
Hives can be extremely itchy, and the natural instinct would be to scratch the area that is bothering you. But scratching hives can make them more inflamed and cause them to spread.... read more ›
Sweat, fabrics (wool, polyester), pet dander, hot or cold weather, and harsh soaps are common triggers. Others include: Dry skin. It could get scaly, tight, and easy to crack, which can lead to a flare-up.... view details ›
- Celiac disease.
- Rheumatoid arthritis.
- Thyroid disease.
Dermatographia, also called skin writing, is a condition that causes an allergic reaction when skin is scratched. This reaction looks like hives or welts. It may even happen when the skin is rubbed when pressure is applied. Experts estimate that 2% to 5% of people have dermatographism.... see more ›