Understanding LAMA Inhalers for Severe Asthma

Are you wondering what a long-acting muscarinic antagonist (LAMA) is and how it works? If so, I thought the same thing the first time I heard the term. Turns out it's simply a type of asthma medication that is recommended for certain people. But let's give it some context first.

Revisions to our national asthma guidelines

In December 2020, the national panel of experts that guides health care professionals on how best to treat asthma revised its official guidelines. This is important because it's the first time the asthma treatment guidelines have been revised since 2007. Since then, researchers have learned much more about the origins of asthma and how the disease changes over time. New medications have also been approved during the last decade or so. So, updating the guidelines was in order.¹

One focus of the new guidelines is a class of drugs that, to date, has not been used extensively in asthma treatment. This type of medication is called a long-acting muscarinic antagonist. The revised guidelines cover how and when to incorporate LAMAs into asthma treatment plans for certain groups, including as part of an approach known as triple therapy.¹

What is a long-acting muscarinic antagonist?

LAMAs are a class of inhaled bronchodilators that affect the airways for at least 12 hours (as opposed to giving rapid relief). "Muscarinic" refers to a type of receptor in smooth muscle cells, such as those that line your airways. A muscarinic antagonist interferes with a neurotransmitter called acetylcholine, which causes smooth muscle cells to contract. In other words, this type of medicine prevents airways from tightening and helps them to relax.^2,3

There are a variety of LAMAs currently available, but most are used only for people with COPD, not asthma. Currently, only 1 LAMA medication is approved for use in treating asthma. It is tiotropium bromide, brand name Respimat.⁴

What is the difference between a LABA and a LAMA?

Another class of medications, long-acting beta-agonists (LABAs), is more commonly used to treat severe asthma. LABAs are also long-acting bronchodilators. Frequently, they are combined with an inhaled steroid when the steroid alone does not sufficiently provide asthma control.⁴ Examples include formoterol and salmeterol. When a LABA and a LAMA are both added to an inhaled steroid, the combination is known as triple therapy.

Who needs a long-acting muscarinic antagonist or triple therapy?

In general, people who need more than an inhaled steroid to treat their asthma are those classified as having persistent, poorly controlled asthma. These are people who have ongoing symptoms, even after consistently taking their inhaled steroids. Inhaled steroids stop and control airway inflammation caused by asthma. But sometimes that is not enough to control asthma adequately.¹

The next step is to combine the inhaled steroid with a LABA, such as those listed Yet, some people with severe asthma are still unable to achieve satisfactory control even with these combinations.¹

So the next step may be to add a LAMA to the mix, creating triple therapy. In fact, a growing body of research evidence suggests that LAMAs can be useful in treating severe, uncontrolled asthma, even when added to a combination of both inhaled steroids and a LABA.⁵

How are LAMAs used in people with asthma?

The new asthma treatment guidelines offer specific instructions as to the use of a long-acting muscarinic antagonist:⁴

• In children under age 12, and in most people age 12 or older with asthma not controlled by an inhaled corticosteroid alone, adding a LABA rather than a LAMA to an inhaled corticosteroid is preferred.
• For people age 12 and older who are not well-controlled with an inhaled steroid, either a LABA or a LAMA may be added.
• When a combination of an inhaled steroid and a LABA does not produce asthma control in those age 12 and older, a LAMA may also be added.

Please note that the guidelines do not address the use of LAMAs at all in those under the age of 12.

Who should not use a LAMA or triple therapy for asthma?

For people who have severe uncontrolled asthma, it's always wise to be under the care of an asthma expert who is familiar with all the available options. Always thoroughly discuss and understand the risks vs. the benefits of any new treatment.

But here are a few cases where a LAMA is not recommended:⁴

• Children under the age of 12
• Anyone with glaucoma
• People with urinary retention

Do you use a LAMA or triple therapy for your own or your child's asthma treatment? Share your thoughts and experiences in the comments below.