Respiratory Pharm: Beta2-Agonist Bronchodilators?

Red inhaler

In this lecture, we will quickly break down the different types of respiratory drugs and how they are somehow connected with anaphylactic medications, which are both necessary to increase oxygenation inside the body, specifically, the lungs.


If there’s the presence of lung inflammation, there are a couple of ways to decrease the condition – BAM and SLM.

BAM stands for:

  • Beta2-agonist
  • Anticholinergic
  • Methylxanthines

These are categorized as bronchodilators.

On the other hand, SLM stands for:

  • Steroids
  • Leukotrienes
  • Mast cells stabilizers

These are categorized as anti-inflammatory medications.

Increasing Oxygen

In order to increase oxygen supply, bronchodilators are administered to enlarge the big branch or big stump inside the lungs that lead to the bronchioles, similar to vasodilation. Once the “highways” are dilated, the amount of oxygen that is going down the lungs also increases.

Bronchodilator: Beta2-Agonists

One of the drug types under the bronchodilator team is the beta2-agonists. Beta2-agonists usually end in “-terol” like Albuterol. But what exactly are beta2-agonists and how do they differ from other bronchodilators?

What you have to remember is that inside the body, there are response systems known as beta receptors. Beta receptors are also known as sympathomimetic receptors that activate the fight and flight response. Which is why, if a person is experiencing a stressful situation, like being chased by a bear, what your body will do is to react by activating the fight and flight response. During the fight and flight response, the lungs will breath faster and better, and the heart will pump harder.

To easily identify beta receptors between the heart and lungs, remind yourself this:

Beta receptors inside the heart are called beta-1. A person has one heart; hence, beta-1. On the other hand, a person has two lungs which is why the beta receptors inside the lungs are known as beta-2.

Agonizing the Receptors

Beta2-agonists tend to “agonize” the receptors in a way that it’s like instigating a fight for the receptors at the bronchial site to react and expand. Somehow, beta2-agonists stimulate the cells responsible for the sympathomimetic response to dilate and allow more oxygen to flow inside.

Beta Blockers

Beta-1 blockers or what is commonly known as beta-blockers are medications that decrease the heart rate. Beta-blockers usually end in “-olol” like metoprolol or atenolol. These drugs are non-specific which means that it aside from blocking beta-1 receptors of the heart, they would also affect the beta-2 receptors of the lungs. Therefore, it is important to watch out for the client’s decreased breathing.

The Fast-Acting Beta2-Agonist

Albuterol is the only rapid-acting respiratory medication. Albuterol is the type of medication that can help a client during crisis or rescue situation, much like fast-acting insulins.


After beta2-agonists, the next medication from the BAM category is anticholinergic. Anticholinergics are medications that have a “drying” effect on the client due to the deactivation of the parasympathetic response and the activation of the sympathomimetic response.

This will be further discussed in the following lecture, as well as looking further into methylxanthines. For other nursing topics, visit us at

See you in our next article!