Leukotriene modifiers can help control asthma symptoms by reducing inflammation and airway constriction. These medications alter the activity of leukotrienes, which drive inflammation and play a role in asthma pathology.
Leukotriene receptor blockers (or antagonists) and leukotriene synthesis blockers are two classes of modifiers.
They work differently but ultimately aim to reduce the amount of leukotrienes in the body. This is an effect that can help relieve asthma symptoms.
Read on to learn more about using leukotriene modifiers for asthma.
People can use leukotriene modifiers to treat asthma symptoms or even prevent them from occurring. Two classes of leukotriene modifiers are available to help prevent and treat asthma symptoms: Leukotriene receptor blockers and leukotriene synthesis blockers.
Montelukast (Singulair) and zafirlukast (Accolate) are cysteinyl leukotriene receptor blockers. Zileuton (Zyflo) is a leukotriene synthesis blocker. Both drugs work on leukotrienes that the body produces from different inflammatory cells.
Receptor blockers vs. synthesis blockers
Cysteinyl leukotriene receptor blockers
- difficulty breathing
- chest tightness
On the other hand, zileuton
- mucus secretion
- fluid buildup in the lungs
- narrowing of the bronchioles (the small airways in the lungs)
Overall, zileuton helps to reduce asthma exacerbations and improves symptoms.
The table below summarizes the names, age ranges, and dosages (in milligrams) of leukotriene modifiers that doctors use to treat and prevent chronic asthma symptoms.
|Generic name||Brand name||Age||Dosage|
|Accolate||for adults and children aged 5 years or older||• Adults and children aged 12 years and older: 20 mg twice daily|
• Children between 5 and 11 years old: 10 mg twice daily
|montelukast||Singulair||for adults and children aged 12 months or older||• Children 12–23 months old: 4 mg packet of oral granules once daily|
• Children 2–5 years old: 4 mg chewable tablet or 4 mg oral granules once daily
• Children 6–14 years old: 5 mg chewable tablet once daily
• Adults and adolescents aged 15 years and older: 10 mg once daily
|zileuton||Zyflo||for adults and children aged 12 years or older||Two 600 mg extended-release tablets twice daily|
Each type of leukotriene modifier has its own specific side effects. People generally have good toleration of leukotriene receptor blockers — montelukast and zafirlukast — and these have few severe side effects.
Leukotriene receptor blockers
The following table lists the
|Side effects of montelukast in children||Side effects of montelukast in adults||Side effects of zafirlukast in adults and children aged 5 years or older|
|nausea||flu||upper respiratory tract infection|
|infection of the larynx or pharynx||pain in belly||nausea|
|sinus infection||upset stomach||vomiting|
|ear infection||cough||upset stomach|
|viral infection||depression||pain in the belly|
|aggression||suicidal thoughts||general unwellness (malaise)|
Although zileuton works slightly differently in the body compared to montelukast and zafirlukast, it has similar side effects, such as:
- sinus infection
- throat pain
More severe side effects may include liver toxicity and neuropsychiatric effects, such as trouble sleeping and change in behavior.
Doctors prescribe leukotriene modifiers to people with chronic asthma but must respect the age ranges for each drug. For example, zafirlukast is not suitable for children under five years old, while montelukast is generally safe for children from 12 months old.
Treatment for an asthma attack requires a quick-acting drug. Leukotriene modifiers are not quick-acting. Doctors may provide an action plan for people or parents of children with asthma. The action plan describes what to do during an asthma attack. Quick-acting drugs for treating asthma attacks typically come in an inhaler.
People allergic to specific active or inactive ingredients in leukotriene modifier forms should not take these drugs. Doctors will likely
Zafirlukast is also not suitable for people with liver problems due to the possibility of the following:
- risk of liver enzyme levels increasing in the blood
- risk of acute hepatitis
- risk of hyperbilirubinemia, another liver condition
Since zileuton is a different type of leukotriene modifier, it has different
Zafirlukast may also play a role in relieving allergies, but this is an off-label use. Off-label use is when a doctor prescribes a medication for a condition that the Food and Drug Administration (FDA) has not yet approved it for.
Leukotriene modifiers help treat asthma symptoms by altering the action of leukotrienes, molecules that play a role in airway inflammation and constriction.
Leukotriene receptor blockers — including montelukast and zafirlukast — and the leukotriene synthesis blocker zileuton are two types of leukotriene modifier drugs.
A doctor can determine which leukotriene modifier is the best choice for someone with asthma, and they will likely consider the person’s age, co-occurring health conditions, and side effect risks.