Principles of Drug Therapy

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The aims of drug treatment are to control symptoms, achieve best lung function and maintain best lung function with the lowest effective doses of medication and the fewest possible adverse effects.

In adults and children, the pattern, severity and level of asthma control will determine which regimen is most appropriate to achieve these aims.

Good asthma control is defined as all of the following:

  • Minimal symptoms during day and night
  • Minimal need for reliever medication
  • No exacerbations
  • No limitation of physical activity
  • Normal lung function (FEV1 and/or PEFR >80% predicted or best).

For those with severe asthma, patients and health professionals may need to consider carefully the trade-off between symptom control, safety (especially the prevention of life-threatening asthma episodes) and the adverse effects and risks of medication.

For more information on interaction between asthma severity and asthma control, see Ongoing Care.

Note on ICS-equivalents

Consistent with international guideline publications, stated inhaled corticosteroid doses are expressed in beclomethasone dipropionate (BDP-HFA)-equivalents for simplicity and editorial economy, and do not indicate a recommendation of any particular agent within this drug class. To calculate equivalent doses of other formulations, see Table 1. ICS dose equivalents.

Summary of practice points

Level of evidence
Principles of drug treatment in adults
Prescribe reliever therapy for all patients with symptomatic asthma:
  • An inhaled short-acting beta2 agonist (SABA) is standard reliever therapy and should be carried by all patients [√] (except those using the budesonide-eformoterol combination (Symbicort) according to the maintenance and reliever regimen)
  • Eformoterol is an effective reliever in patients using the Symbicort maintenance and reliever regimen. (I) These patients ought not require a separate SABA. [√]

[√]

I
Treatment with a preventer medication is recommended for patients who have asthma symptoms more than three times per week or use SABA more than three times per week. I
In adults in whom preventer medication is indicated, start with a low dose of inhaled corticosteroids (ICS). Once control is achieved, titrate the dose of ICS to the lowest dose at which effective control of asthma is maintained. Those with moderate persistent asthma will need the addition of a long-acting beta2 agonist (LABA). I

 
On average, little additional improvement in symptoms or lung function is gained by increasing doses above 800 mcg/day budesonide, 320 mcg/day ciclesonide* or 500 mcg/day fluticasone propionate/beclomethasone dipropionate-HFA. I
Early treatment with ICS in people with persistent symptoms and impaired lung function leads to better lung function in the medium term, and may help prevent the development of irreversible airflow limitation, compared with delayed treatment. [√]
In adults, initial therapy with ICS is superior to treatment with a leukotriene receptor antagonist (LTRA), cromone or theophylline for improving lung function and reducing symptoms. I
In adults with moderate-to-severe persistent asthma who experience asthma symptoms despite ICS treatment, the addition of a LABA improves symptom control (I), and reduces ICS requirements (II), compared with ICS alone. I

II
The two LABAs differ in onset of therapeutic action: eformoterol has a rapid onset (1-3 minutes) while salmeterol has a slower onset (15-20 minutes).
  • The combination of budesonide plus eformoterol (Symbicort) can be used either as maintenance therapy, or maintenance and reliever therapy. [√]
  • The combination of fluticasone plus salmeterol (Seretide) is used only as maintenance therapy. [√]
 [√]
As with ICS alone, combination ICS-LABA therapy should be stepped down to the lowest dose that maintains asthma control. [√]
When stepping down combination ICS-LABA therapy, consider ceasing LABA treatment when symptoms are controlled by a daily ICS dose of 100 mcg BDP-HFA or equivalent. IV
Regular treatment with SABA has no benefit over as-needed use. I
Principles of drug treatment in children and adolescents
Prescribe a SABA as reliever therapy for all children with symptomatic asthma. [√]
In children, start preventer medication with low-dose ICS, montelukast or inhaled cromone. (II)
Most young children have infrequent asthma episodes, which can be managed with bronchodilators as needed and do not require any long-term preventive medications. [√]
In children, ICS doses greater than 250 mcg BDP-HFA or equivalent should be prescribed only on specialist advice. [√]
Once control is achieved, step down the dose of ICS to the lowest dose at which effective control of asthma is maintained. [√]
There is limited evidence for the efficacy of LABAs in children I 

*Nominal maximal dose pending further investigation to establish ciclesonide dose-response curve for efficacy