Leukotriene modifiers are a group of medications that help breathing, so they are typically
used to manage nasal congestion and inflammation associated with allergic rhinitis, as well
as to manage narrowing and obstruction of the airways in obstructive lung diseases,
such as asthma.
Asthma is characterized by chronic inflammation in the lungs, as well as asthma exacerbations
or attacks, where certain triggers, such as viruses, allergens, stress, aspirin and exercise,
lead to reversible bronchial smooth muscle spasms and mucus production, both of which
make it hard to breathe.
As a result, clients experience symptoms like dyspnea, wheezing, coughing, and chest tightness.
Now, leukotriene modifiers act by decreasing the action of leukotrienes, which are inflammatory
molecules produced and released by certain immune cells, such as mast cells, to trigger
an inflammatory response.
Once released, leukotrienes bind to leukotriene receptors located on the bronchial smooth
muscles, causing them to contract, as well as on the mucous glands to increase mucus
secretion.
In addition, leukotrienes increase blood vessel permeability, which results in fluid leakage
and edema.
Now, leukotriene modifiers can be classified into two groups, based on their mechanism
of action.
On the one hand, leukotriene receptor antagonists, such as montelukast and zafirlukast, bind
to and block leukotriene receptors on the airways, preventing leukotrienes from binding.
On the other hand, leukotriene synthesis inhibitors, such as zileuton, inhibit the enzyme that
produces leukotrienes.
Now, regardless of the exact mechanism, the net effect is decreased leukotriene action,
leading in turn to decreased smooth muscle contraction in the airways, decreased mucus
secretion, and decreased inflammation.
Alright, now unlike other medications that are used for asthma, leukotriene modifiers
are typically administered orally and have slower onset of action, which is why they
are only used as part of maintenance therapy and not during an acute attack.
In addition, they are especially effective in preventing exercise- or aspirin- induced
asthma.
However, leukotriene modifiers can have side effects.
The most common side effects are mild and nonspecific, such as a headache, gastrointestinal
disturbances, fatigue, and a skin rash or urticaria.
However, they can also lead to severe allergic reactions as well as neuropsychiatric effects
like agitation, sleep disturbances, depression, and suicidal ideation.
Montelukast has a boxed warning for these neuropsychiatric events.
Contraindications and cautions In general, leukotriene modifiers should be
used with caution in those with severe asthma, as well as in clients with existing depression
or suicidal ideation.
Zafirlukast and zileuton are also potentially hepatotoxic, and zafirlukast is contraindicated
in clients with active liver disease.
Nursing Considerations & Client Education OK, before administering a leukotriene modifier,
assess your client’s respiratory status, and confirm your client’s liver function
tests are normal.
Also be sure the client does not have a history of depression or suicidal ideation.
Then, teach your client that leukotriene modifiers are maintenance medications that are to be
used along with their other routine respiratory medications.
Remind them that leukotriene modifiers should never be used to treat an acute asthma attack.
Also instruct your client to continue to take the medication regularly even when they are
feeling well, and not to discontinue it abruptly.
Finally, if your client plans to become pregnant or breastfeed while taking a leukotriene modifier,
instruct them to talk to their health care provider.
While your client is taking a leukotriene modifier, periodically monitor their liver
function, especially if they are prescribed zafirlukast or zileuton.
Stress the importance of reporting any symptoms that may indicate liver problems, such as
fatigue, loss of appetite, epigastric pain, or nausea.
Also closely monitor your client for neuropsychiatric problems like changes in mood or behavior
and teach them to report problems such as sleep disturbances, depression, agitation,
or thoughts of suicide right away.
Now, if your client is prescribed montelukast to prevent exercise-induced bronchoconstriction,
teach them to take the medication 2 hours before exercising.
If the medication is in the form of an oral granule packet, instruct them to take it within
fifteen minutes of opening the packet.
Let them know that they can either put the granules directly in their mouth, or they
can mix it with a spoonful of applesauce or ice cream.
If zafirlukast is prescribed, teach your client to take the medication on an empty stomach,
1 hour before or 2 hours after meals.
Lastly, if your client is prescribed zileuton, be sure they know to take their medication
with food.
Alright, as a quick recap...
Leukotriene modifiers help improve breathing by decreasing bronchoconstriction, mucus production
and inflammation.
They are often used to treat obstructive lung diseases, allergic rhinitis, and nasal congestion.
Leukotriene modifiers are maintenance medications and are not effective in treating acute asthma
attacks.
Nursing considerations include client education and monitoring for serious side effects, including
hepatotoxicity and neuropsychiatric problems like depression and suicidal thoughts.