The preferred treatment for many patients is desensitization to aspirin, undertaken at a clinic or hospital specializing in such treatment. In the United States, the Scripps Clinic in San Diego, CA, the Massachusetts General Hospital in Boston, MA, the Brigham and Women's Hospital in Boston, MA, National Jewish Hospital in Denver and Stanford University Adult ENT Clinic have allergists who routinely perform aspirin desensitization procedures for patients with aspirin-induced asthma. Patients who are desensitized then take a maintenance dose of aspirin daily and while on daily aspirin they often have reduced need for supporting medications, fewer asthma and sinusitis symptoms than previously, and many have an improved sense of smell. Desensitization to aspirin reduces the chance of nasal polyp recurrence, and can slow the regrowth of nasal polyps. Even patients desensitized to aspirin may continue to need other medications including nasal steroids, inhaled steroids, and leukotriene antagonists.

Leukotriene antagonists and inhibitors (montelukast, zafirlukast, and zileuton) are often helpful in treating the symptoms of aspirin-induced asthma. Some patients require oral steroids to alleviate asthma and congestion, and most patients will have recurring or chronic sinusitis due to the nasal inflammation.

Medications used to treat asthma are divided into two general classes: quick-relief medications used to treat acute symptoms; and long-term control medications used to prevent further exacerbation. Antibiotics are generally not needed for sudden worsening of symptoms.

When asthma is unresponsive to usual medications, other options are available for both emergency management and prevention of flareups. For emergency management other options include:

- Oxygen to alleviate hypoxia if saturations fall below 92%.

- Corticosteroid by mouth are recommended with five days of prednisone being the same 2 days of dexamethasone. One review recommended a seven-day course of steroids.

- Magnesium sulfate intravenous treatment increases bronchodilation when used in addition to other treatment in moderate severe acute asthma attacks. In adults it results in a reduction of hospital admissions.

- Heliox, a mixture of helium and oxygen, may also be considered in severe unresponsive cases.

- Intravenous salbutamol is not supported by available evidence and is thus used only in extreme cases.

- Methylxanthines (such as theophylline) were once widely used, but do not add significantly to the effects of inhaled beta-agonists. Their use in acute exacerbations is controversial.

- The dissociative anesthetic ketamine is theoretically useful if intubation and mechanical ventilation is needed in people who are approaching respiratory arrest; however, there is no evidence from clinical trials to support this.

- For those with severe persistent asthma not controlled by inhaled corticosteroids and LABAs, bronchial thermoplasty may be an option. It involves the delivery of controlled thermal energy to the airway wall during a series of bronchoscopies. While it may increase exacerbation frequency in the first few months it appears to decrease the subsequent rate. Effects beyond one year are unknown.

- Evidence suggests that sublingual immunotherapy in those with both allergic rhinitis and asthma improve outcomes.

- Omalizumab may also be useful in those with poorly controlled allergic asthma.

- It is unclear if non-invasive positive pressure ventilation in children is of use as it has not been sufficiently studied.

Often surgery is required to remove nasal polyps, although they typically recur, particularly if aspirin desensitization is not undertaken. 90% of patients have been shown to have recurrence of nasal polyps within 5 years after surgery, with 47% requiring revision surgery in the same time period.

Allergen immunotherapy is useful for environmental allergies, allergies to insect bites, and asthma. Its benefit for food allergies is unclear and thus not recommended. Immunotherapy involves exposing people to larger and larger amounts of allergen in an effort to change the immune system's response.

Meta-analyses have found that injections of allergens under the skin is effective in the treatment in allergic rhinitis in children and in asthma. The benefits may last for years after treatment is stopped. It is generally safe and effective for allergic rhinitis and conjunctivitis, allergic forms of asthma, and stinging insects.

The evidence also supports the use of sublingual immunotherapy for rhinitis and asthma but it is less strong. For seasonal allergies the benefit is small. In this form the allergen is given under the tongue and people often prefer it to injections. Immunotherapy is not recommended as a stand-alone treatment for asthma.

Several medications may be used to block the action of allergic mediators, or to prevent activation of cells and degranulation processes. These include antihistamines, glucocorticoids, epinephrine (adrenaline), mast cell stabilizers, and antileukotriene agents are common treatments of allergic diseases. Anti-cholinergics, decongestants, and other compounds thought to impair eosinophil chemotaxis, are also commonly used. Though rare, the severity of anaphylaxis often requires epinephrine injection, and where medical care is unavailable, a device known as an epinephrine autoinjector may be used.

The management of rhinitis depends on the underlying cause.

For allergic rhinitis, intranasal corticosteroids are recommended. For severe symptoms intranasal antihistamines may be added.

Short-acting beta-agonists like salbutamol or terbutaline or long-acting beta-agonists like salmeterol and formoterol dilate airways which relieve the symptoms thus reducing the severity of the reaction. Some patients also use it just before work to avoid a drop in the FEV.

Anti-inflammatory agents like corticosteroids, LKTRA or mast cell stabilizers can also be used depending on the severity of the case.

Epinephrine (adrenaline) is the primary treatment for anaphylaxis with no absolute contraindication to its use. It is recommended that an epinephrine solution be given intramuscularly into the mid anterolateral thigh as soon as the diagnosis is suspected. The injection may be repeated every 5 to 15 minutes if there is insufficient response. A second dose is needed in 16-35% of episodes with more than two doses rarely required. The intramuscular route is preferred over subcutaneous administration because the latter may have delayed absorption. Minor adverse effects from epinephrine include tremors, anxiety, headaches, and palpitations.

People on β-blockers may be resistant to the effects of epinephrine. In this situation if epinephrine is not effective intravenous glucagon can be administered which has a mechanism of action independent of β-receptors.

If necessary, it can also be given intravenously using a dilute epinephrine solution. Intravenous epinephrine, however, has been associated both with dysrhythmia and myocardial infarction. Epinephrine autoinjectors used for self-administration typically come in two doses, one for adults or children who weigh more than 25 kg and one for children who weigh 10 to 25 kg.

Mast cell stabilizers can help people with allergic conjunctivitis. They tend to have delayed results, but they have fewer side-effects than the other treatments and last much longer than those of antihistamines. Some people are given an antihistamine at the same time so that there is some relief of symptoms before the mast cell stabilizers becomes effective. Doctors commonly prescribe lodoxamide and nedocromil as mast cell stabilizers, which come as eye drops.

A mast cell stabilizer is a class of non-steroid controller medicine that reduces the release of inflammation-causing chemicals from mast cells. They block a calcium channel essential for mast cell degranulation, stabilizing the cell, thus preventing the release of histamine. Decongestants may also be prescribed. Another common mast cell stabilizer that is used for treating allergic conjunctivitis is sodium cromoglicate.

Antihistamines (both H1 and H2), while commonly used and assumed effective based on theoretical reasoning, are poorly supported by evidence. A 2007 Cochrane review did not find any good-quality studies upon which to base recommendations and they are not believed to have an effect on airway edema or spasm. Corticosteroids are unlikely to make a difference in the current episode of anaphylaxis, but may be used in the hope of decreasing the risk of biphasic anaphylaxis. Their prophylactic effectiveness in these situations is uncertain. Nebulized salbutamol may be effective for bronchospasm that does not resolve with epinephrine. Methylene blue has been used in those not responsive to other measures due to its presumed effect of relaxing smooth muscle.

Antihistamines such as diphenhydramine and chlorpheniramine are commonly used as treatment. People treated with H1 antihistamines exhibit reduced production of histamine and leukotrienes as well as downregulation of adhesion molecule expression on the vasculature which in turn attenuates allergic symptoms by 40–50%.

Dual-action medications are also prescribed frequently. Olopatadine (Patanol) and ketotifen fumarate (Alaway or Zaditor) both provide protection by acting as an antihistamine and a mast cell stabilizer together. Patanol is a prescription medication, whereas ketotifen fumarate is not.

A systematic review of 30 trials, with 17 different treatment comparisons found that all topical antihistamines and mast cell stabilizers included for comparison were effective in reducing symptoms of seasonal allergic conjunctivitis. There was not enough evidence to determine differences in long-term efficacy among the treatments.

Many of the eye drops can cause burning and stinging, and have side-effects. Proper eye hygiene can improve symptoms, especially with contact lenses. Avoiding precipitants, such as pollen or mold can be preventative.

Although feline asthma is incurable, ongoing treatments allow many domestic cats to live normal lives. Feline asthma is commonly managed through use of bronchodilators for mild cases, or glucocorticosteroids with bronchodilators for moderate to severe cases.

Previously, standard veterinary practice recommended injected and oral medications for control of the disease. These drugs may have systemic side effects including diabetes and pancreatitis. In 2000, Dr. Philip Padrid pioneered inhaled medications using a pediatric chamber and mask using Flovent(r) (fluticasone) and salbutamol. Inhaled treatments reduce or eliminate systemic effects. In 2003 a chamber called the AeroKat Feline Aerosol Chamber was designed specifically for cats, significantly improving efficiency and reducing cost for the caregiver. Medicine can also be administered using a human baby spacer device. Inhaled steroid usually takes 10-14 days to reach an effective dose.

Intranasal corticosteroids are used to control symptoms associated with sneezing, rhinorrhea, itching, and nasal congestion. Steroid nasal sprays are effective and safe, and may be effective without oral antihistamines. They take several days to act and so must be taken continually for several weeks, as their therapeutic effect builds up with time.

In 2013, a study compared the efficacy of mometasone furoate nasal spray to betamethasone oral tablets for the treatment of people with seasonal allergic rhinitis and found that the two have virtually equivalent effects on nasal symptoms in people.

Systemic steroids such as prednisone tablets and intramuscular triamcinolone acetonide or glucocorticoid (such as betamethasone) injection are effective at reducing nasal inflammation, but their use is limited by their short duration of effect and the side-effects of prolonged steroid therapy.

Allergen immunotherapy (AIT, also termed desensitization) treatment involves administering doses of allergens to accustom the body to substances that are generally harmless (pollen, house dust mites), thereby inducing specific long-term tolerance. Allergy immunotherapy can be administered orally (as sublingual tablets or sublingual drops), or by injections under the skin (subcutaneous).

Interventions include intravenous (IV) medications (e.g. magnesium sulfate), aerosolized medications to dilate the airways (bronchodilation) (e.g., albuterol or ipratropium bromide/salbutamol), and positive-pressure therapy, including mechanical ventilation. Multiple therapies may be used simultaneously to rapidly reverse the effects of status asthmaticus and reduce permanent damage of the airways. Intravenous corticosteroids and methylxanthines are often given. If the person with a severe asthma exacerbation is on a mechanical ventilator, certain sedating medications such as ketamine or propofol, have bronchodilating properties. According to a new randomized control trial ketamine and aminophylline are also effective in children with acute asthma who responds poorly to standard therapy.

Underlying disease must be controlled to prevent exacerbation and worsening of ABPA, and in most patients this consists of managing their asthma or CF. Any other co-morbidities, such as sinusitis or rhinitis, should also be addressed.

Hypersensitivity mechanisms, as described above, contribute to progression of the disease over time and, when left untreated, result in extensive fibrosis of lung tissue. In order to reduce this, corticosteroid therapy is the mainstay of treatment (for example with prednisone); however, studies involving corticosteroids in ABPA are limited by small cohorts and are often not double-blinded. Despite this, there is evidence that acute-onset ABPA is improved by corticosteroid treatment as it reduces episodes of consolidation. There are challenges involved in long-term therapy with corticosteroids—which can induce severe immune dysfunction when used chronically, as well as metabolic disorders—and approaches have been developed to manage ABPA alongside potential adverse effects from corticosteroids.

The most commonly described technique, known as sparing, involves using an antifungal agent to clear spores from airways adjacent to corticosteroid therapy. The antifungal aspect aims to reduce fungal causes of bronchial inflammation, whilst also minimising the dose of corticosteroid required to reduce the immune system’s input to disease progression. The strongest evidence (double-blinded, randomized, placebo-controlled trials) is for itraconazole twice daily for four months, which resulted in significant clinical improvement compared to placebo, and was mirrored in CF patients. Using itraconazole appears to outweigh the risk from long-term and high-dose prednisone. Newer triazole drugs—such as posaconazole or voriconazole—have not yet been studied in-depth through clinical trials in this context.

Whilst the benefits of using corticosteroids in the short term are notable, and improve quality of life scores, there are cases of ABPA converting to invasive aspergillosis whilst undergoing corticosteroid treatment. Furthermore, in concurrent use with itraconazole, there is potential for drug interaction and the induction of Cushing syndrome in rare instances. Metabolic disorders, such as diabetes mellitus and osteoporosis, can also be induced.

In order to mitigate these risks, corticosteroid doses are decreased biweekly assuming no further progression of disease after each reduction. When no exacerbations from the disease are seen within three months after discontinuing corticosteroids, the patient is considered to be in complete remission. The exception to this rule is patients who are diagnosed with advanced ABPA; in this case removing corticosteroids almost always results in exacerbation and these patients are continued on low-dose corticosteroids (preferably on an alternate-day schedule).

Serum IgE can be used to guide treatment, and levels are checked every 6–8 week after steroid treatment commences, followed by every 8 weeks for one year. This allows for determination of baseline IgE levels, though it’s important to note that most patients do not entirely reduce IgE levels to baseline. Chest X-ray or CT scans are performed after 1–2 months of treatment to ensure infiltrates are resolving.

Recovery is directly dependent on the duration and level of exposure to the causative agent. Depending on the severity of the case, the condition of the patient can improve dramatically during the first year after removal from exposure.

Three basic types of procedures are used for treating the affected workers: reducing a worker's exposure, removing a worker from the environment with the asthma-causing agent, and treatment with asthma medications. Completely stopping exposure is more effective treatment than reducing exposure. By reducing exposure, the probability of suffering another reaction is lowered. Methods of reducing exposure include transferring an affected worker to a position without the relevant asthmagen, use of respiratory protection, and engineering controls. In 1984 innovator David Cornell discovered and invented effective control equipment in the UK for the removal of many harmful workplace fumes. 'BOFA' extraction products are now found in over 100 countries worldwide.

People affected by occupational asthma that occurred after a latency period, whether a few months or years, should be immediately removed from exposure to the causative agent. However, this can entail severe socio-economic consequences for the worker as well as the employer due to loss of job, unemployment, compensation issues, quasi-permanent medical expenditures, and hiring and re-training of new personnel. This can be mitigated by transferring the worker within a company.

The best treatment is to avoid the provoking allergen, as chronic exposure can cause permanent damage. Corticosteroids such as prednisolone may help to control symptoms but may produce side-effects.

Antihistamines can alleviate some of the milder symptoms of an allergic reaction, but do not treat all symptoms of anaphylaxis. Antihistamines block the action of histamine, which causes blood vessels to dilate and become leaky to plasma proteins. Histamine also causes itchiness by acting on sensory nerve terminals. The most common antihistamine given for food allergies is diphenhydramine.

Epinephrine is another name for the hormone adrenaline, which is produced naturally in the body. An epinephrine injection is the first-line treatment for severe allergic reactions (anaphylaxis). If administered in a timely manner, epinephrine can reverse its effects.

Epinephrine relieves airway swelling and obstruction, and improves blood circulation; blood vessels are tightened and heart rate is increased, improving circulation to body organs. Epinephrine is available by prescription in an autoinjector.

Avoiding allergens will help prevent symptoms. Allergies that a child has to the family pet can be controlled by removing the animal and finding it a new home. Exterminating cockroaches, mice and rats and a thorough cleaning can reduce symptoms of an allergy in children. Dust mites are attracted to moisture. They consume human skin that has come off and lodged in, furniture, rugs, mattresses, box springs, and pillows. The child's bedding can be covered with allergen-proof covers. Laundering of the child's clothing, bed linens and blankets will also reduce exposure.

Exposure to allergens outside the home can be controlled with the use of air conditioners. Washing the hair, taking a bath or shower before bedtime can be done to remove allergens that have been picked up from outside the home. If grass or grass pollen is an allergen it is sometimes beneficial to remain indoors while grass is being cut or mowed. Children with allergies to grass can avoid playing in the grass to prevent allergic symptoms. Staying out of piled leaves in the fall can help. Pets returning into the home after being outdoors may track in allergens.

Corticosteroids: For years, there was no treatment for atopic eczema. Atopy was believed to be allergic in origin due to the patients’ extremely high serum IgE levels, but standard therapies at the time did not help. Oral prednisone was sometimes prescribed for severe cases. Wet wraps (covering the patients with gauze) were sometimes used in hospitals to control itching. However, the discovery of corticosteroids in the 1950s, and their subsequent incorporation in topical creams and ointments, provided a significant advancement in the treatment of atopic eczema and other conditions. Thus, the use of topical steroids avoided many of the undesirable side-effects of systemic administration of corticosteroids. Topical steroids control the itching and the rash that accompany atopic eczema. Side-effects of topical steroid use are plentiful, and the patient is advised to use topical steroids in moderation and only as needed.

Immune modulators: Pimecrolimus and tacrolimus creams and ointments became available in the 1980s and are sometimes prescribed for atopic eczema. They act by interfering with T cells but have been linked to the development of cancer.

Avoiding dry skin: Dry skin is a common feature of patients with atopic eczema (see also eczema for information) and can exacerbate atopic eczema.

Avoiding allergens and irritants: See eczema for information.

Cat allergies can often be controlled with over the counter or prescription medications. Antihistamines and decongestants may provide allergy relief.

Currently there is no cure for allergic reactions to peanuts other than strict avoidance of peanuts and peanut-containing foods. Extra care needed for food consumed at or purchased from restaurants. The principal treatment for anaphylaxis is epinephrine as an injection.