Asthma (Pediatric) Xử trí

SEVERITY ASSESSMENT OF ASTHMA EXACERBATION

Asthma exacerbation is an acute or subacute deterioration in symptom control that is sufficient to cause distress or risk to health and would need specialist consult or requires treatment with systemic corticosteroids. Note for episodes of progressive increase in wheeze and shortness of breath, cough, especially when the child is asleep, lethargy or reduced exercise tolerance, impairment of daily activities (including feeding), and poor response to reliever medication.

Severity must be assessed immediately through history, physical examination, and objective measures of lung function while initiating treatment with a short-acting beta₂-agonist, and O₂ - PEF or FEV₁ and arterial O₂ saturation should be measured to determine the degree of hypoxemia. PEF or FEV₁ are more reliable indicators of airflow limitation severity and may also help determine patients who require hospitalization (ie patients with pre-treatment FEV₁ or PEF <25% predicted or personal best or patients with post-treatment FEV₁ or PEF <40% predicted or personal best). In patients <18 years old, consider using a validated clinical assessment tool, such as the Pediatric Respiratory Assessment Measure (PRAM).

Evaluate the patient’s severity for risk of death based on the following: Past history of near-fatal asthma requiring intubation and mechanical intubation; prior (within 1 year) hospitalization or emergency care visit due to asthma exacerbation; currently using or recently stopped oral glucocorticosteroids; currently not on inhaled glucocorticosteroids; overdependent on rapid-acting inhaled beta₂-agonists (ie use of >1 canister per month); history of psychiatric disease or psychosocial problems; history of poor compliance with asthma medication or asthma action plan; asthma patients with food allergy or comorbidities including pneumonia, diabetes and arrhythmia; and difficult to perceive airflow obstruction or severity.

A severe asthma attack requires close supervision, as it may be life-threatening. Treatment should continue until PEF or FEV₁ returns to their previous ideal value or plateau. Asthma phenotyping is recommended for patients diagnosed with severe asthma. Patients with residual type 2 airway inflammation are likely to respond to add-on biologic type 2-targeted therapy (eg Omalizumab, Mepolizumab, Benralizumab, Dupilumab).

Immediate medical attention is needed when there is a presence of acute distress in the child; inhaled bronchodilator did not relieve the child’s symptoms promptly; there is progressively shorter period of relief after doses of rapid acting beta₂-agonist; and there is a need for a child <1 year to have repeated inhaled rapid-acting beta₂-agonist administration over several hours.

Immediate hospital transfer is indicated in children ≤5 years old with any of the following: Inability to speak or drink; cyanosis or subcostal retractions; respiratory rate >40/min; SaO₂ at <92% when without breathing support; silent chest sounds upon auscultation; no improvement seen after initial bronchodilator treatment (unresponsive to ≥4 puffs of inhaled short-acting beta₂-agonist in <4 hours or persistent tachypnea after three doses of inhaled short-acting beta₂-agonist within 12 hours even if with clinical signs of improvement); and availability of acute treatment is affected by patient's environment or caretaker's ability to manage acute asthma at home.

Initial Assessment of Acute Asthma Exacerbation

Mild Exacerbation

• Talks in phrases, can lie down, not agitated
• Normal or mildly increased respiratory rate
• No or mild accessory muscle use and/or expiratory wheeze
• Normal air entry or mild basal decrease
• SaO₂ ≥94% 
• PRAM 1-3

Moderate Exacerbation

• Talks in phrases, prefers sitting to lying, not agitated
• Increased respiratory rate ≤40/min
• Expiratory wheeze with or without inspiratory wheezing
• Decreased air entry basal or widespread
• SaO₂ ≥92% (≥92% for children ≤5 years)
• PRAM 4-7

Severe or Life-threatening Exacerbation

•  Unable to speak, drink or lie-down
• SaO₂ at <92%
• Respiratory rate >40/min
• Silent chest or only inspiratory wheezing
• PRAM 8-12

Acutely Life-threatening Exacerbation 

• Drowsy, confused or cyanosed
• PRAM 11-12
   

Patient, guardian, or caregiver education includes skills training, symptom monitoring, and a written personal asthma action plan. This aims to actively involve the children, their families, and caregivers in managing asthma. Education should be provided over several visits. Studies have shown that asthma control is improved with the use of a written asthma management plan together with careful verbal explanation of the treatment regimen. Develop a patient-doctor partnership. The objective is to give patients the ability to control their asthma with guidance from health care professionals.

The patient, parents, and caregivers should be able to apply the following objectives: Avoid triggers and aggravating factors; take medications accurately and appropriately; understand the difference between “controller” and “reliever” medications; train about correct inhalation technique; and monitor asthma control status; recognize signs of worsening asthma and take appropriate action; and seek medical help when necessary.

Written Asthma Action Plan

A written asthma action plan may help patients and parents, guardians, or caregivers recognize and respond appropriately to an asthma attack. This should include specific, individualized instructions about medications and medical care access. Instructions on the administration of inhaled short-acting beta₂-agonists should be provided.

Changes to medications may include the following: Increasing as-needed inhaled low-dose corticosteroid-Formoterol doses; the use of an inhaler containing rapid-onset long-acting beta₂-agonist with low-dose corticosteroid; other inhaled corticosteroids and inhaled corticosteroid-long-acting beta₂-agonist maintenance-controlled regimens; and a short-course oral corticosteroids for patients unresponsive to increased doses of reliever and controller medications, rapid deterioration, PEF or FEV₁ <60% of personal best, or a history of sudden severe exacerbations.

Controller Medications

Preferred Therapy

Corticosteroids (Inhaled)

Inhaled corticosteroids are the most effective anti-inflammatory medications used for asthma and are the preferred controller medications for patients with persistent asthma of all levels of severity. Discontinuation is followed by deterioration of control within a week to month in some patients. To minimize side effects, upon achievement of control, corticosteroids should be titrated carefully to the lowest effective dose to maintain control. Ciclesonide, a prodrug that is activated only in the lungs, may be an alternative with decreased oropharyngeal side effects. Combination with Formoterol as initial treatment is preferred over daily inhaled corticosteroid monotherapy due to issues with treatment adherence. Addition of long-acting inhaled beta₂-agonist is preferred when daily low-dose inhaled corticosteroid fails. This improves lung function and symptoms, reduces exacerbations, decreases the need for short-acting beta₂-agonists, achieves faster clinical control of asthma and may also be used to prevent exercise-induced asthma.

Alternative or Add-on Therapy

Anticholinergic (Inhaled)

Example drugs: Ipratropium bromide, Tiotropium bromide

Inhaled anticholinergics are considered an alternative to short-acting inhaled beta₂-agonists because they may have a slower onset of action and/or a higher risk for side effects. These have an additive effect when nebulized together with a short-acting beta₂-agonist for exacerbations of asthma. Inhaled anticholinergics are considered in patients who experience adverse effects (eg tachycardia, arrhythmia, tremor) from short-acting beta₂-agonists. These may help improve lung function and decrease the interval to the next asthma exacerbation. Ipratropium bromide should only be considered for exacerbations and not for long-term therapy.

Beta₂-agonists (Inhaled, long-acting)

Inhaled long-acting beta₂-agonists have no effect on airway inflammation and hence are not used as monotherapy. This is most efficacious when given together with inhaled corticosteroids. Rapid clinical control of asthma is achieved more than when inhaled glucocorticosteroids are given alone. Studies have shown increased mortality risk when given alone; it should not be used as a substitute for corticosteroids. Beta₂-agonists cause improved symptom scores, decreased nocturnal asthma symptoms, improved lung function, decreased use of short-acting beta₂-agonists, and a reduced number of exacerbations.

Beta₂-agonist (Oral, long-acting)

Oral, long-acting beta₂-agonists may be considered as an alternative add-on therapy and should always be given with inhaled corticosteroids. This is only used on rare occasions when more bronchodilation is needed. This is less effective than inhaled beta₂-agonists and poses an increased risk of side effects.

Corticosteroids (Oral)

Long-term use (>2 weeks) of oral corticosteroids may be required for severely uncontrolled asthma. Long-term use should be used at the lowest possible dose.

Leukotriene Modifiers (Oral)

When used as add-on therapy, it may reduce the required dose of inhaled corticosteroid for patients with moderate to severe symptoms. When used as monotherapy for control of asthma, leukotriene modifiers are less effective than low-dose inhaled corticosteroids. When using a leukotriene receptor antagonist (ie Montelukast), patients, parents, or caregivers should be advised on the potential risk of neuropsychiatric adverse events.

Monoclonal Antibodies

Example drugs: Benralizumab, Depemokimab, Dupilumab, Mepolizumab, Omalizumab, Tezepelumab

Monoclonal antibodies reduce asthma symptoms and exacerbations and the need for rescue medications. Omalizumab is indicated for patients ≥6 years old with moderate to severe asthma with an allergic component not controlled by inhaled corticosteroids. For patients with severe eosinophilic asthma not controlled by inhaled corticosteroids, Mepolizumab may be considered in patients ≥6 years of age and Benralizumab or Depemokimab in patients ≥12 years of age. Add-on Dupilumab may be considered in patients ≥6 years old with severe eosinophilic/type 2 asthma or in patients aged ≥12 years old in need of oral corticosteroid maintenance therapy. Add-on Tezepelumab may be considered as a maintenance treatment of severe asthma for patients ≥12 years of age. Use of Reslizumab in patients <18 years of age with asthma has not been established.

Theophylline (Oral, extended-release)

Oral theophylline is a treatment option for patients >12 years of age. This is a bronchodilator, which at low doses has anti-inflammatory effects.

Reliever Medications

Preferred Therapy

Beta₂-agonists (Inhaled, short-acting)

Inhaled short-acting beta₂-agonists are the preferred reliever for patients <12 years of age and an alternative reliever to inhaled corticosteroid-Formoterol combination in patients ≥12 years of age. This is the most effective bronchodilator. Inhaled, short-acting beta₂-agonists are the agents of choice for relief of bronchoconstriction during acute episodes of asthma and are useful for pre-treatment prior to exercise, with effects lasting for 0.5 to 2 hours. This is used only when necessary; increased use indicates that management should be reassessed. Concomitant use with corticosteroids is recommended with every intake of a short-acting inhaled beta₂-agonist to prevent side effects of short-acting inhaled beta₂-agonist monotherapy.

Corticosteroids (Inhaled) with Formoterol

Inhaled corticosteroids with Formoterol are the preferred reliever for patients ≥12 years of age. A combination of steroids with Formoterol is preferred for patients previously given Budesonide-Formoterol or Beclometasone-Formoterol maintenance and reliever therapy. This is a reliever-only initial treatment (ie as-needed short-acting inhaled beta2-agonist is no longer recommended due to accumulated reports of increased risk of exacerbations and lower lung function with short-acting inhaled beta₂-agonist monotherapy).

Allergen-Specific Immunotherapy

Allergen-specific immunotherapy is the therapeutic option after strict avoidance of triggers and medical intervention have failed. This may be given as subcutaneous immunotherapy (SCIT) or sublingual immunotherapy (SLIT). Life-threatening anaphylactic reactions have been reported with SCIT use. SLIT has been associated with mild oral and gastrointestinal (GI) symptoms. This may be considered in patients with severe asthma as an add-on therapy only when asthma symptoms and exacerbations are controlled. SLIT may be considered for children with asthma sensitized to ragweed before and during ragweed season if FEV₁ ≥80% predicted. Addition of house dust mite SLIT may be considered in adolescents with asthma with EV₁ of >70% predicted who are sensitized to house dust mite with persisting asthma symptoms unresponsive to low- to medium-dose inhaled corticosteroid therapy. This may reduce symptoms, and medication use, improve allergen-specific and non-specific airway hyperresponsiveness, and possibly prevent asthma development in children with allergic rhinoconjunctivitis. Benefits must be weighed against adverse effects, cost, and inconvenience of length of therapy. Efficacy of extracts or regimens based on clinical trials should be put into consideration before initiating therapy.

Preferred Inhalation Devices

PREFERRED INHALATION DEVICES
Age	Device
0-3 years	Preferred: Pressurized metered-dose inhaler plus dedicated spacer with face mask Alternate: Nebulizer with face mask
4-5 years	Preferred: Pressurized metered-dose inhaler plus dedicated spacer with mouthpiece Alternate: Pressurized metered-dose inhaler plus dedicated spacer with face mask or nebulizer with mouthpiece or face mask
Reference: Global Initiative for Asthma (GINA). Global strategy for asthma management and prevention: Updated 2026.

Initial Treatment of Asthma

Recommended Options for Initial Treatment
Presenting Symptoms	Children 6-11 years	Children ≥12 years
Infrequent asthma symptoms (eg 1-2 days/week or less)	As-needed corticosteroid (inhaled, low-dose) plus Formoterol1 or Corticosteroid (inhaled, low-dose) whenever beta2-agonist (inhaled, short-acting)1 is taken separately or in combination	Preferred As-needed corticosteroid (inhaled, low-dose) plus Formoterol1 Alternative Corticosteroid (inhaled, low-dose) whenever beta2-agonist (inhaled, short-acting)1 is taken separately or in combination
Symptoms occur 3-4 days/week with normal or mildly reduced lung function	Daily corticosteroid (inhaled, low-dose) whenever beta2-agonist (inhaled, short-acting) is taken separately or in combination
Symptoms occur on most days (eg 4-5 days/week) or waking due to symptoms ≥1x/week) Presence of low lung function	Corticosteroid (inhaled, low-dose) with as-needed beta2-agonist (inhaled, short-acting) or Corticosteroid (inhaled, medium-dose) with as-needed beta2-agonist (inhaled, short-acting) or Corticosteroid (inhaled, very low-dose) with Formoterol2	Preferred As-needed corticosteroid (inhaled, low-dose) plus Formoterol2 Alternative Corticosteroid (inhaled, low-dose) plus beta2-agonist (inhaled, long-acting) plus  As-needed corticosteroid (inhaled, low-dose) whenever beta2-agonist (inhaled, short-acting)1 is taken separately or in combination
Daily asthma symptoms, waking due to symptoms ≥1x/week, with low lung function	Corticosteroid (inhaled, medium-dose) with beta2-agonist (inhaled, long-acting) plus Corticosteroid (inhaled, low-dose) whenever beta2-agonist (inhaled, short-acting)1 is taken separately or in combination or Corticosteroid (inhaled, very low-dose) plus Formoterol2	Preferred Corticosteroid (inhaled, medium-dose) plus Formoterol2 Alternative Corticosteroid (inhaled, medium-dose) plus  As-needed corticosteroid (inhaled, low-dose) whenever beta2-agonist (inhaled, short-acting)1 is taken separately or in combination
Reference: Global Initiative for Asthma (GINA). Global strategy for asthma management and prevention: Updated 2026. 1As anti-inflammatory reliever (AIR). 2As maintenance and reliever therapy (MART).

Management Plans for Long-Term Asthma Control

Recommended Medications Based on Level of Control
Treatment Steps	Daily Controller Medications
	Children ≤5 years	Children 6-11 years	Children ≥12 years
Step 1	Consider this step for children with infrequent viral wheezing and no or few interval symptoms No daily medication required Other controller options: Intermittent, short-course corticosteroid at onset of viral illness Reliever: As needed beta2-agonist (inhaled, short-acting)	Preferred controller: As-needed corticosteroid (inhaled, low-dose) plus Formoterol1 or  Corticosteroid (inhaled, low-dose) if taking beta2-agonist (inhaled, short-acting)2	Controller: As needed corticosteroid (inhaled, low-dose) plus Formoterol1 Alternative controller: Corticosteroid (inhaled, low-dose) if taking beta2-agonist (inhaled, short-acting)1,2   Other controller options (any of the following): Daily leukotriene modifier Add-on house dust mite sublingual immunotherapy (SLIT) Preferred reliever: As needed corticosteroid (inhaled, low-dose) plus Formoterol1 Alternative reliever: As-needed corticosteroid (inhaled, low-dose) plus beta2-agonist (inhaled, short-acting)1,2 or  As-needed beta2-agonist (inhaled, short-acting)
Step 2	Consider this step for children with asthma symptoms not well-controlled or ≥1 severe exacerbations per year  Preferred controller: Daily corticosteroid (inhaled, low-dose) Other controller options: Daily leukotriene modifier Intermittent, short-course corticosteroid (inhaled) at onset of respiratory illness Preferred reliever same as Step 1	Preferred controller: Daily corticosteroid (inhaled, low-dose) Other controller options (any of the following): As-needed corticosteroid (inhaled, low-dose) plus Formoterol1  Corticosteroid (inhaled, low-dose) if taking beta2-agonist (inhaled, short-acting)2  Daily leukotriene modifier Preferred reliever: As-needed corticosteroid (inhaled, low-dose) plus Formoterol1 or  As-needed corticosteroid (inhaled, low-dose) if taking beta2-agonist (inhaled, short-acting)1,2 or  As-needed beta2-agonist (inhaled, short-acting), if AIR is not available	Controller: As needed corticosteroid (inhaled, low-dose) plus Formoterol1 Alternative controller:  Daily corticosteroid (inhaled, low-dose) Preferred and alternative reliever, and other controller options same as Step 1
Step 3	Consider this step for children with asthma not well-controlled on corticosteroid (inhaled, low-dose)  Preferred controller: Corticosteroid (inhaled, double low-dose)2 Specialist referral Preferred reliever same as Step 1	Preferred controller: Corticosteroid (inhaled, medium-dose) or  Corticosteroid (inhaled, low-dose) plus beta2-agonist (inhaled, long-acting) or  Corticosteroid (inhaled, very low-dose) plus Formoterol2,3  Other controller options: Corticosteroid (inhaled, low-dose) plus leukotriene modifier Preferred reliever same as Step 22,5	Controller: Maintenance corticosteroid (inhaled, low-dose plus Formoterol2,3 Alternative controller: Maintenance corticosteroid (inhaled, low-dose) plus beta2-agonist (inhaled, long-acting)   Other controller options (any one of the following): Corticosteroid (inhaled, medium-dose) Add leukotriene modifier Add house dust mite SLIT Preferred and alternative reliever same as Step 15
Step 4	Consider this step for children with asthma not well-controlled on corticosteroid (inhaled, double low-dose) Continue controller treatment Specialist referral Other controller options: Add leukotriene modifier Add-on muscarinic antagonist (long-acting) Preferred reliever same as Step 1	Preferred controller: Corticosteroid (inhaled, medium-dose) plus beta2-agonist (inhaled, long-acting)4  or  Corticosteroid (inhaled, low-dose) plus Formoterol2,3  Other controller options (any of the following): Add-on Tiotropium bromide6 or leukotriene modifier to Step3 preferred controller  Preferred reliever same as Step 22	Controller: Maintenance corticosteroid (inhaled, medium-dose) plus Formoterol2,3 or Alternative controller:  Maintenance corticosteroid (inhaled, medium-dose, or high-dose) plus beta2-agonist (inhaled, long-acting) Other controller options (any of the following): Add-on muscarinic antagonist (long-acting) Add-on leukotriene modifier Add-on house dust mite SLIT Switch to corticosteroid (inhaled, high-dose) Preferred and alternative reliever same as Step 12
Step 5		Preferred controller: Refer for phenotypic assessment with or without higher dose corticosteroid (inhaled) plus beta2-agonist (inhaled, long-acting) or add-on therapy: Anti-IgE (SC Omalizumab8) Anti-IL4α receptor (SC Dupilumab8)  Anti-IL5/5Rα receptor (SC Mepolizumab8)  Muscarinic antagonist (long-acting)8   Other controller options: Add-on corticosteroid (oral, low-dose) as last resort but side effects should be considered Preferred reliever same as Step 27	Controller: Consider corticosteroid (inhaled, high-dose) plus beta2-agonist (inhaled, long-acting)  Consider add-on muscarinic antagonist (long-acting) Refer for phenotypic assessment with or without any of the following: Anti-IgE (SC Omalizumab8)  Anti-IL5 (SC Mepolizumab8) Anti-IL5 receptor (SC Benralizumab, SC Depemokimab9) Anti-IL4α receptor (SC Dupilumab8) Anti-thymic stromal lymphopoietin (SC Tezepelumab10)  Other controller options: Add-on leukotriene modifier Add-on corticosteroid (oral, low-dose) but side-effects should be considered Preferred and alternative reliever same as Step 17
Reference: Global Initiative for Asthma (GINA). Global strategy for asthma management and prevention: Updated 2026. 1As anti-inflammatory reliever (AIR) 2Low-dose inhaled corticosteroids in combination with short-acting inhaled beta2-agonists in separate or combined inhalers.  3As maintenance and reliever therapy (MART). 4Expert referral is recommended for patients 6-11 years old whose asthma is not well-controlled despite treatment with moderate-dose inhaled corticosteroids. 5For patients previously given Budesonide/Formoterol or Beclomethasone dipropionate/Formoterol combination as MART. 6Tiotropium by mist inhaler is only to be given to patients ≥6 years of age with a history of exacerbations. 7For patients previously given low-dose Budesonide/Formoterol or low-dose Beclomethasone dipropionate/Formoterol combination as MART. 8Contraindicated in patients <6 years of age. 9Contraindicated in patients <12 years of age. 10Approved for patients ≥12 years of age.

Stepwise Therapy Based on Control

Step 1 - Use of As-needed Reliever

Low-dose inhaled corticosteroid is preferred for children 6-11 years old and is an alternative controller for children ≥12 years of age if already on a short-acting beta₂-agonist. For children who have infrequent viral wheezing episodes and no or few interval symptoms, use of inhaled short-acting beta₂-agonists is recommended for relief of symptoms. A need for a trial of controller medication is indicated if the child uses a short-acting beta₂-agonist for the relief of symptoms on average of >2x/week for over a month. A combination of low-dose inhaled corticosteroid and Formoterol is preferred for as-needed relief of symptoms in children 6-11 years old and ≥12 years. This is recommended for patients with symptoms <2x/month and with no exacerbation risk factors. This is also recommended as step-down therapy for patients whose asthma is well-controlled on step 2 treatment.

Intermittent inhaled corticosteroids may be an option for children ≤5 years with intermittent viral-induced wheezing and no interval symptoms, especially those with underlying atopy in whom inhaled short-acting beta₂-agonists are insufficient. Patient adherence to medication should be considered when prescribing corticosteroids.

Step 2 - Use of Initial Controller Plus As-needed Reliever

For patients who require controller medications every day in order to maintain control of their asthma. For children whose symptom pattern is consistent with asthma, asthma symptoms that are inadequately controlled, or with ≥1 severe exacerbation/year. This may be used as initial therapy for treatment-naive patients ≤5 years old to control asthma symptoms. A combination of low-dose inhaled corticosteroid and Formoterol is the preferred therapy for step 2, taken as needed for relief of symptoms in children ≥12 years.

Low-dose daily inhaled corticosteroid is preferred for children ≤11 years old. As-needed inhaled corticosteroids may be considered in preschoolers with increased frequency of wheezing secondary to viral infections after initial treatment with daily inhaled corticosteroids. This should be given for at least 2-3 months to achieve good asthma control. Leukotriene modifiers may reduce symptoms and oral corticosteroid use in pediatric patients with persistent asthma. Use of daily low-dose inhaled corticosteroid with long-acting beta₂-agonist as initial maintenance controller treatment is an option for patients ≥12 years given controller medications for the first time.

Step 3 - Use of Additional Controller Plus As-needed Reliever and Expert Referral

Before stepping up, reconfirm the asthma diagnosis, check inhaler technique and compliance with medications, and inquire about exposure to risk factors. For patients whom symptoms were not controlled by low-dose inhaled corticosteroids after 2-3 months of initial therapy or if exacerbations persisted. The use of low-dose inhaled corticosteroid with Formoterol as maintenance therapy and for symptom relief is preferred for children ≥12 years. Medium-dose inhaled corticosteroid is preferred for children ≤5 years (double low-daily dose) and 6-11 years old and may be an alternative for children ≥12 years.

Expert referral is recommended for children ≤5 years if symptom control remains poor and/or flare-ups persist, or if side effects from therapy are observed. Addition of oral leukotriene modifiers to low-dose corticosteroids may be considered in children ≥6 years old. Addition of house dust mite sublingual immunotherapy (SLIT) may also be considered in patients ≥12 years of age sensitized to house dust mite with allergic rhinitis and with suboptimally controlled asthma and FEV₁ >70% predicted. For patients with daily occurrence of symptoms, currently smoking, low lung function, recent severe exacerbation or history of life-threatening exacerbation, impaired perception of bronchoconstriction, severe airway hyperresponsiveness and/or current exposure to a seasonal allergic trigger, starting with maintenance and reliever therapy (MART) may be considered.

Step 4 - Daily Controller and Reliever Therapy Continued and Expert Referral

Reassess inhaler technique, medication adherence, and trigger factors and reinvestigate diagnosis. If symptom control is still not achieved, consider increasing the dose of inhaled corticosteroid until improvement is seen. Consider expert referral if increasing the dose of inhaled corticosteroids fails or if symptom control remains poor and/or flare-ups persist.

Add-on therapy with the following until symptom control is achieved: Oral leukotriene modifiers, long-acting inhaled beta₂-agonist in combination with inhaled corticosteroid, Theophylline, or low-dose oral corticosteroid. May add intermittent inhaled corticosteroid to daily corticosteroid dose if the main concern is exacerbation in children ≤5 years. A long-acting muscarinic agent may be considered by a specialist as an add-on treatment in children ≤5 years of age. Tiotropium by mist inhaler is only to be given to patients ≥6 years old with a history of exacerbations. Routine use of Theophylline as a controller is not recommended for children 6-11 years.

Addition of house dust mite SLIT may be considered in sensitized patients ≥12 years of age with allergic rhinitis and FEV₁ >70% predicted. For patients ≥6 years old, being considered for high-dose inhaled corticosteroids, advise should be given about the increased risk for side effects and should be referred for expert assessment.

Step 5 - Add-on Treatment and Expert Referral

For patients ≥6 years old, step 5 is recommended if symptoms are not controlled by step 4 medications. The patient should be referred to a specialist for further diagnostic evaluation, including assessment of phenotype and additional treatment. An addition of Tiotropium or a monoclonal antibody may be considered if symptoms are still not controlled. Tiotropium via mist inhaler may be considered for adolescent patients ≥6 years old with a history of exacerbations despite combination therapy in step 3.  Addition of anti-IgE Omalizumab may be considered in pediatric patients ≥6 years of age diagnosed with moderate-severe asthma when control is not achieved despite combination treatments. Additional anti-IL-5 Mepolizumab may be considered for patients ≥6 years of age, and anti-IL5 receptor Benralizumab or Depemokimab in patients ≥12 years of age with severe uncontrolled eosinophilic asthma despite adherence to step 4 regimen. Add-on anti-IL4α receptor subcutaneous Dupilumab may be considered in patients aged ≥6 years old with severe eosinophilic or type 2 asthma or in patients aged ≥12 years old in need of oral corticosteroid maintenance therapy. Add-on anti-thymic stromal lymphopoietin (anti-TSLP) (Tezepelumab) may be considered for patients aged ≥12 years old with severe asthma.

Maintaining Control of Asthma

A stepwise approach to therapy is the advancement to the next step of therapy if control is not reached or obtained with the current treatment. Treatment should be individualized based on the availability of antiasthmatic medications, resources of the healthcare system, individual patient circumstances, and cost.

Step Down

Once control is achieved and maintained for ≥3 months, gradual stepwise reduction in treatment may be attempted. This is not applicable for patients at risk of exacerbations or persistent and fixed airflow limitation. For patients currently on inhaled corticosteroids, consider reducing the dose by 25-50% at 2-3-month intervals. If given long-acting beta₂-agonists and add-on agents, specialist referral is advised.

Patients adequately controlled by low-dose inhaled corticosteroids or a leukotriene modifier, inhaled low-dose corticosteroids may be reduced to once-daily dosing. May shift to as-needed low-dose inhaled corticosteroid-Formoterol therapy as MART. May switch to inhaled corticosteroid when short-acting inhaled beta₂-agonist is taken. Discontinuation of inhaled corticosteroid therapy in adolescents is not advised. For patients adequately controlled by medium- or high-dose inhaled corticosteroid, 50% dose reduction of inhaled corticosteroid may be done. Addition of leukotriene modifiers may be considered when stepping down inhaled corticosteroid doses.

In patients ≥12 years on inhaled corticosteroid-Formoterol combination therapy as maintenance and reliever, reduce maintenance inhaled corticosteroid-Formoterol therapy from medium-dose to low-dose or low-dose to once-daily dose and continue as-needed low-dose corticosteroid-Formoterol reliever regimen. Replace oral corticosteroids with high-dose inhaled corticosteroids and add biologic therapy if T2 high severe asthma. In patients ≥12 years old on low-dose maintenance inhaled corticosteroid and long-acting beta₂-agonists, the dose may be reduced to once-daily dosing. Identify the patient's inflammatory type based on sputum eosinophil count or Fractional exhaled Nitric Oxide (FeNO) to assess eligibility for various add-on treatments.

Step Up

Consider step-up if control is not maintained (review patient medication techniques, compliance, non-pharmacological control, and comorbidities). A sustained step-up of 2-3 months duration may be considered in patients who are not responding to the initial treatment regimen despite good treatment adherence and removal of modifiable risk factors. A short-term step-up of 1-2 weeks involved increasing the dose of inhaled corticosteroid for 1-2 weeks for special situations such as in the presence of viral infections or seasonal allergens. Daily adjustment is needed for patients prescribed as-needed low-dose inhaled corticosteroid-Formoterol combination for mild asthma, or maintenance/reliever therapy using low-dose inhaled corticosteroid-Formoterol.

Difficult-to-Treat Asthma

Difficult-to-treat asthma is defined as asthma with persistent symptoms and/or exacerbations despite adherence to medium- or high-dose asthma regimens (eg step 4-5 of the management plan for long-term asthma, medium-dose inhaled corticosteroids with a long-acting inhaled beta₂-agonist or leukotriene modifier, continuous/frequent therapy with oral corticosteroids). Risk factors include incorrect inhaler technique, poor adherence, comorbidities, exacerbation triggers, overuse of a long-acting inhaled beta₂-agonist, psychosocial factors, and adverse effects of medications.

The steps to optimize management are as follows: Check, review, correct and demonstrate inhaler technique every visit; confirm if patient/caregiver has a written asthma action plan and if the patient/caregiver understands what is included; treat comorbidities and modifiable risk factors; consider lifestyle modifications, avoidance of triggers and other non-pharmacological treatments; and consider the following if not previously given (non-biologic therapies [eg Tiotropium bromide, Azithromycin, long-acting beta₂-agonist], high-dose inhaled corticosteroids).

Assess the patient's inflammatory phenotype if unresponsive to optimized management strategies, and consider add-on biologic treatments (eg Mepolizumab, Depemokimab, Dupilumab, Benralizumab, etc) once severe asthma phenotype has been identified. Recommended biologic type 2-targeted treatments include: Omalizumab for patients aged ≥6 years old with sensitization to inhaled allergens on skin prick testing or specific IgE, total serum IgE and body weight within specified dosing range, number of exacerbations within the last year considered under severe allergic asthma and/or with childhood-onset asthma; Mepolizumab (for patients aged ≥6 years old) or Benralizumab or Depemokimab (for patients aged ≥12 years old), in patients with blood eosinophils above specified level, with number of exacerbations within the last year considered under severe eosinophilic asthma, with nasal polyposis, who are on oral corticosteroid maintenance therapy at baseline and/or with low lung function (eg FEV₁ <65%); Dupilumab for patients aged ≥6 years old with severe eosinophilic/type 2 inflammation characterized by raised eosinophils and/or raised FeNO, for patients aged ≥12 years old who require maintenance therapy with oral corticosteroids, or for patients with concomitant moderate/severe atopic dermatitis; and Tezepelumab may be considered for patients aged ≥12 years old without elevated type 2 markers characterized by raised eosinophils and/or raised FeNO. Review the patient’s response after 3-4 months.

Advise the patient or caregiver to follow up after 3-6 months to assess the patient's response to treatment changes. Referral to a specialist or to a severe asthma clinic is recommended if asthma is still uncontrolled even with modifications and optimization of treatment. If with uncontrolled symptoms and/or exacerbations after a treatment step-down, return to the previous regimen and refer to a specialist or to a severe asthma clinic. Assess the patient's inflammatory phenotype and consider add-on biologic treatments once identified. Review the patient’s response after 3-4 months.

Treatment of Acute Exacerbations

The inhaler should be shaken before each actuation to prevent inadvertent administration of ultra-high doses. Proper technique should be applied when administering bronchodilators. It is given by spacer 1 puff at a time; may use tidal breathing if too breathless for single breath with breath hold. It may also be given with face-mask attachment for younger children; 1 puff at a time with 5-6 breaths after each puff.

In patients with a poor response or worsening condition after first-line treatment, continue therapy while arranging hospital admission. Oral Prednisone/Prednisolone may be considered with dose of 1-2 mg/kg/day for 1-5 days up to maximum dose of 20 mg/day for 0-2 years old, 30 mg/day for 3-5 years old and 40 mg/day for 6-11 years old or Dexamethasone 0.6 mg/kg/day for 2 days.