Bronchodilators And Heart Health
Bronchodilators are great for opening airways and quickly ending asthma attacks. They are also great for keeping airways open long-term and helping to control asthma. However, bronchodilators and inhalers may also cause side effects on your heart too. So, here’s what to know about bronchodilators and heart health.
Let’s take a trip back in time
I think it helps here to get a historical perspective here. Epinephrine was the first bronchodilator. It was discovered in 1901 and was first used to treat asthma around 1910. It was soon learned that it quickly ended asthma attacks.
At first, physicians had no idea how it worked. The effort to learn how it worked led to the discovery that asthma is caused by bronchospasms. This is when muscles wrapped around airways spasm and constrict. These muscles then squeeze airways to cause your asthma symptoms of shortness of breath, chest tightness, and wheezes.
By the 1930s primitive nebulizers were available. They were made of glass and were bulky. This allowed asthmatics to inhale epinephrine. Affordable ones were handheld and operated by a rubber squeeze bulb. More costly ones were run by electricity. It wasn’t until 1956 that an epinephrine inhaler was available. It was called the Medihaler Epi. A second inhaler with a similar medicine called Isopreterenol became available. It was called the Medihaler Iso.
These inhalers were awesome for asthmatics. They gave them access to rescue medicine. They could use it whenever they needed, wherever they were. Sales of these inhalers soon escalated. Within a few years every asthmatic who wanted one owned one. This was nice because they gave asthmatics access to quick relief. No longer did they have to go to their doctors to treat asthma attacks.
Then researchers saw a stunning statistic! Between 1959 and 1966, deaths from asthma attacks nearly doubled. This rise in asthma-related deaths parallelled rescue inhaler sales. Also, 86 percent of those who died owned one of these rescue inhalers. Therefore, it only made sense to blame the inhalers.1
Why do bronchodilators affect the heart?
Bronchodilators are also called beta 2 adrenergic (B2) agonists. This is because, once inhaled, they bind with B2 receptors lining the airways. This causes a series of chemical reactions that make bronchial smooth muscles relax. This opens airways to make breathing easier.
However, they also impact alpha 1 and alpha 2 receptors in the heart. This causes your heart to speed up and beat harder and your blood pressure to spike. Cardiac side effects was suspected of causing asthma inhaler-related deaths.
It was just a theory. This theory said that asthmatics were relying on their inhalers rather than seeking help. In some cases, asthmatics didn’t decide to seek help until it was too late. Some asthmatics died with inhalers clutched in their hands. Now, whether this caused the rise in asthma deaths is not certain. However, it was a viable theory.
People with asthma kept their inhalers
Obviously, rescue inhalers were not taken away from asthmatics. But, a warning was sent out to physicians. They were instructed to educate their patients with asthma. They were told to encourage their patients to use their inhalers exactly as instructed. If they needed their inhalers more than prescribed, they were told to seek help.
Also, a recommendation was made to not treat asthma with drugs alone. Efforts must also be made to learn what's triggering the asthma and to control these triggers.
Asthma-related deaths soon declined.1
How can we avoid side effects of inhalers?
Epinephrine is rarely used to treat asthma today. Epi inhalers are still on the market, but their dose is relatively low. Most doctors and experts like me don't recommend them. Instead, we recommend asthmatics see a doctor.
The rescue medicine most of us use today is albuterol (introduced to the market in 1981). This has a stronger effect on B2 receptors and a much less effect on alpha receptors. Therefore, it has much less of an effect on the heart. Side effects due to inhaler use are generally considered negligible.
However, that’s if the medicine is used as prescribed. Another change today is an emphasis on asthma control. Today, there are also Long-Acting Beta 2 agonists. These are combined with long-acting inhaled corticosteroids in medicines like Advair, Symbicort, Dulera, and Breo. These are meant to keep airways open long term and control asthma. They offer a higher dose of medicine. So, the recommendation is that you should never use these inhalers more than twice per day. This is to prevent cardiac side effects due to inhaler use.
So, there’s a reason we asthma experts say what we say. There's a reason most bronchodilators are only available with a prescription from a doctor. Use your inhalers exactly as prescribed. If you need to use your rescue inhaler more often than prescribed, seek medical attention. Don't use your controller medicines more than twice daily.
The reason for this caveat is noble. It's to make sure you can have access to these great asthma medicines and you stay heart healthy!
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