As CBD has attracted attention for treating numerous inflammatory conditions, scientists are investigating whether this versatile phytocannabinoid could benefit people with asthma.

In 2015, an estimated 358 million people worldwide had asthma. Thirty years earlier, only 183 million people were reported to have been diagnosed. These figures show that asthma is becoming increasingly common. Its growing prevalence has naturally prompted medical researchers to seek new, effective treatments.

In this article, we will review existing research on CBD and asthma, examining how CBD might be used effectively and what might maximize its benefits.

What is asthma?

Asthma is a condition in which inflammation and narrowing of the airways leading to the lungs make breathing difficult. Coughing, shortness of breath and chest tightness are its classic, most common symptoms. Severe asthma can even make speaking difficult and prevent an active life.

Symptoms can range from very mild to life-threatening. They may appear following exposure to triggers such as allergens, or as occasional asthma attacks. Allergic asthma is considered an atopic condition, meaning a genetic predisposition to allergic diseases, a category that also includes dermatitis, skin inflammation, and food allergies.

Unfortunately, there is no definitive cure for asthma. Treatment focuses on reducing the intensity and frequency of attacks and identifying and removing triggers.

Asthma attacks are temporary periods when symptoms intensify. In most cases, factors such as dust, cigarette smoke, exercise or food allergies trigger attacks. As the airways become inflamed during an attack, less air can pass through the bronchioles and the body must work harder to obtain the oxygen it needs. Attacks can last from a few seconds to several days.

Asthma symptoms

  • Shortness of breath
  • Wheezing
  • Chest tightness
  • Chronic cough
  • Fatigue
  • Waking up tired

Emergency signs during an asthma attack

  • Inability to speak
  • Labored breathing
  • Extreme shortness of breath
  • No relief even after medication
  • Blue lips

What types of asthma are there?

Allergic asthma

Allergies occur when the immune system is activated by particular compounds. Allergens that cause a runny nose, watery eyes and itchy skin can also cause asthma symptoms.

When we encounter these compounds, the immune system identifies them and raises an alarm. Specialized cells called mast cells release neurotransmitters such as histamine, which cause most of the adverse effects. These immune cells are also found in the airways leading to the lungs, where they prevent infectious organisms from entering and making us ill.

During an allergic asthma attack, immune cells acting to protect us make the situation worse. Histamine released by mast cells causes the airways to fill with fluid and close.

Nonallergic asthma

The central nervous system controls our airways. During exercise, for example, it widens them to allow more air into the lungs. It then narrows them as much as possible to limit heat loss and keep infectious organisms out.

In some cases of nonallergic asthma, symptoms are mediated by central nervous system dysfunction that narrows the airways. Medicines or exercise can cause this type of asthma.

Asthma symptom severity

Doctors generally assess asthma symptom severity using a four-stage scale.

1. Intermittent asthma

Symptoms occur on fewer than two days a week and do not disrupt daily activities. This level generally involves brief attacks and rare nighttime symptoms.

2. Mild persistent asthma

Symptoms occur on more than two days a week but do not prevent normal daily activities. This level may or may not involve occasional nighttime attacks.

3. Moderate persistent asthma

Symptoms occur daily and interfere with normal activities. This level involves daytime and nighttime attacks, and medication is generally needed to prevent symptoms.

4. Severe persistent asthma

Symptoms occur throughout the day and substantially affect normal activities. Patients at this level generally struggle with physical activity and frequently experience nighttime attacks.

What does the research show?

In a 2015 animal study in Brazil, laboratory animals were divided into three groups, with one group receiving 5 mg/kg of CBD for two days. When researchers measured inflammatory activity afterward, they found significant reductions in every inflammatory marker except IL-10. This finding suggests that CBD can reduce inflammatory factors causing asthma symptoms.

* IL-10: A cytokine released by Th2 and mast cells.

Asthma caused by an allergic reaction involves an increase in specific immune-reactive cells. Research indicates that CBD specifically targets many Th2 cytokines, including IL-6, IL-2, TNF-a, IFN-c, IL-6, IL-12 and IL-17.

This also means that CBD's anti-inflammatory effects operate at several different levels. Such multilevel treatment approaches are much more effective than treatments focused on only one aspect of inflammation.

A 2012 study at the University of Florence in Italy investigated the endocannabinoid system's role in asthma.

The study found that activation of cannabinoid receptors at nerve endings in the bronchi acted like a bronchodilator, opening the airways and allowing unrestricted breathing. It also concluded that preventing endocannabinoid breakdown could reduce inflammation-related pain.

* Bronchodilator: A class of asthma medicines that works by widening the bronchi.

According to the research, because CBD helps activate these receptors, it has potential as a bronchodilator and effective analgesic.

Another animal study conducted in Italy in 2008 investigated the role of CB1 and CB2 cannabinoid receptors in preventing asthma symptoms.

It concluded that both receptors are involved in protecting the lungs, and that targeting them could potentially offer preventive treatment for people with asthma.

CBD's potential effects in people with asthma

  • Preventing the development of inflammation associated with allergic and nonallergic asthma
  • Resisting immune cell migration toward inflamed airway tissue
  • Easing symptoms of related conditions such as insomnia, anxiety and mood disorders
  • Relaxing muscles in the airways and chest to reduce asthma symptoms

Other cannabinoids, such as THC, may also offer substantial benefits against asthma

  • Relaxing the airways to allow better oxygen flow
  • Reducing several different inflammatory effects linked to asthma
  • Relaxing chest and airway muscles to reduce symptoms

Important note: Please consult your doctor before using CBD oil.

Finding the right CBD dose for managing asthma symptoms takes some trial and error, because each person may respond differently.

Most people use a moderate or high-strength CBD dose for symptoms or everyday relief. However, the article advises starting with a small amount and increasing gradually over time to ensure there is no allergy to the product. Misuse could ultimately worsen asthma symptoms.

For people prone to allergies in particular, the article describes a small allergy test: placing a little CBD oil on the back of the hand. If there is no allergic reaction after about an hour, it suggests taking a few drops orally. If another hour passes without a reaction, it suggests beginning with a low-strength CBD product.

Click to read our article “How is CBD oil used?”

Click to read our article “What are CBD's side effects?”

Wishing you good health...