Marijuana and Asthma

Medical Marijuana for Asthma

You might instinctively assume marijuana causes asthma, but there are actually many documented cases of smoked cannabis being able to halt ongoing asthma attacks. There is also evidence suggesting that the endocannabinoid system plays an important role in the activity of the respiratory system, and can even modulate that activity in a number of ways. 

In addition, both preclinical and clinical research shows that cannabis has the potential to aid with asthma treatment as a bronchodilator. However, the studies that have been done on the full effects of cannabis and asthma were either limited in scope or conducted on animals. More research is needed to confirm whether cannabis can be helpful for asthmatics. If you are considering trying cannabis to help your asthma, you should first consult a doctor who specializes in cannabinoids.

In terms of the best strains of marijuana to treat asthma, you can narrow down the possibilities by looking at strains that are high in the terpenes pinene, limonene or eucaliptul, according to the research. 

Medical Studies on Marijuana and Asthma

Given that marijuana can interact with the endocannabinoid receptors in our lungs, can it treat asthma? Many researchers have wondered the same thing, and set out to study how cannabis impacts this condition. There was some concern that cannabis smoke would act like tobacco smoke, and add to the risk factors for asthma. As it turns out, the research suggests that cannabis is a fairly reliable bronchodilator. In other words, it is able to open up the airways that are constricted during an asthma attack. This is in stark contrast to the smoke from tobacco, which is a noted bronchoconstrictor. Tobacco smoke can close airways up, actually triggering asthma attacks.

Studies on smoked marijuana that includes low levels of THC (1-2.6%) have found that cannabis can act as a bronchodilator. One study found that it was able to halt bronchospasm and associated hyperinflation of the lungs almost immediately. Another study also found cannabis smoke caused bronchodilation — with more pronounced effects when using more THC — and noted that it did not come along with any central respiratory depression. While this research is promising, both of these studies were limited by a relatively small sample size. They also both utilized cannabis with much lower levels of THC than are found in most available strains of marijuana. Future research might investigate more common chemotypes of cannabis, or THC alone, to find out how these influence lung function.

Overall, the research does support the idea that cannabis can help treat asthma as a bronchodilator, and potentially even help in other ways. Still, more research is needed to confirm and better understand these findings. If you are considering using cannabis for your own asthma, make sure to consult a physician who specializes in cannabinoid treatments to find out if it could be right for you.

CBD and Asthma

Some studies have also focused on CBD’s effects on asthma. These studies have also been promising — if limited — since they relied on animal models of asthma. For example, in rodent models of asthma, CBD was able to reduce airway inflammation and the damage and scarring to lung tissue associated with asthma. Similarly, guinea pig models of asthma showed that CBD was able to help reduce airway constriction. Researchers on both studies believe that CBD could be beneficial for treating this condition, but human studies are needed to confirm these findings.

Terpenes and Asthma

In addition to these two cannabinoids, which show potential for aiding asthma, one of the cannabis terpenes (the chemicals in cannabis which gives it flavor, aroma, and a wide range of pharmacological effects) may also be able to help. Eucalyptol is a terpene present in many strains of marijuana (although not all), and it is also present in some other plants like the Eucalyptus tree. Studies on eucalyptol show that it can also be helpful for treating airway inflammation. In one study asthma sufferers taking eucalyptol supplements saw a significant decrease in asthma related symptoms. In another study, those taking eucalyptol were able to reduce the other asthma medications they were taking as a result of their eucalyptol treatment. 

Limonene, one of the major terpenes in marijuana, has also shown potential benefits for asthma. One 2010 study found that limonene may have potential anti inflammatory efficacy for the treatment of bronchial asthma…”

Pinene, another very prevalent terpene in marijuana, and very common to conifers, has also shown bronchodilator effects.

How Does Marijuana Affect Asthma

When it comes to understanding how marijuana works to treat asthma, we first need to understand how cannabis works in general. Cannabis interacts with our bodies primarily through the endocannabinoid system — which maintains homeostasis or balance for many key functions such as sleep, hunger, mood, immune response, and memory. This important system in the human body is made up of three parts, endocannabinoids, receptors and enzymes. 

Endocannabinoids are natural chemicals produced by the body. These activate or modulate the endocannabinoid receptors (such as CB1 and CB2 receptors) to trigger the system’s balancing effects. Enzymes then metabolize the endocannabinoids and clear them from the body. 

While endocannabinoids usually activate this system, it can also be triggered by the cannabinoids found in the cannabis plant. These chemicals are also able to interact with the endocannabinoid system, and thus impact many of it’s important functions. This is how cannabis is able to impact the human body in so many noticeable ways. 

These endocannabinoid receptors are located in many parts of the human body, and as it turns out, this includes the lungs. In fact, almost every cell type present in the human lungs expresses an endocannabinoid receptor. Both CB1 and CB2 receptors can be found in the lungs and in the bronchial tissue — with CB1 levels being significantly higher than CB2. This suggests that the lungs are susceptible to the effects of the endocannabinoid system, and thus can be affected by cannabis. 

In studies looking at the effects of cannabinoids and endocannabinoids on these receptors, it has been shown that they can be potent anti-inflammatory agents. This could help to explain why we see many studies and accounts of cannabis (or its most common ingredients THC and CBD) acting as a bronchodilator, opening up airways and reducing mucus production.

Best Marijuana Strains for Asthma

There are thousands of marijuana strains out there, and choosing the best one for you can be a complicated endeavor. Looking at the body of evidence we can see that THC and CBD could be effective for asthma, even in very low concentrations (1-3% THC). The terpenes eucaliptul, limonene and pinene could also alleviate some of the symptoms of asthma, and the entourage effect theory that suggests a potential synergy between cannabinoids and terpenes even suggest some of these terpenes could potentiate the effects of THC and CBD. If your physician and you decided to try marijana treatment for your asthma, you should look for chemovars (AKA strains) high in these cannabinoids and terpenes. In case you live in a state where there’s an active marijuana program, you could ask for the Certificate of Analysis (CoA) of the product you’re considering in order to examine the main cannabinoids and terpenes in it.

If you prefer avoiding the high associated with THC, you can look for chemovars like Ringo’s Gift, that are high in CBD and have both pinene and limonene. If you have any concerns about smoking marijuana, you can try other delivery methods, such as vaporizers, inhalers, tinctures or edibles. Some of the knowledge about these compounds is based on preliminary research, and though they are all generally recognized as safe (GRAS) by the FDA, you should consult with your treating physician before trying marijuana for asthma.

Potential side effects of cannabis use

While some asthma sufferers report big improvements using marijuana for their asthma, it is not without the risk of side effects. In general, the side effects of marijuana can include temporary shifts in cognitive function, coordination and memory, dry eyes and mouth, increased heart-rate, and anxiety or paranoia. For most, these are rare, mild, or manageable, but for some they pose limits to functionality that make cannabis a less effective treatment.

Perhaps the most important side effect for asthma sufferers to consider is the allergies that cannabis can cause itself. In mild cases, cannabis allergies can cause increased congestion, runny nose, watery eyes, post-nasal drip, and itchy eyes or nose. These could be distressing to asthma sufferers and potentially harmful for those who suffer from asthma which is triggered by allergies. In more serious cases, people report skin rashes from contact with cannabis resin, worsening asthma symptoms, or even anaphylactic shock. If you have an allergy to cannabis, it may not be a helpful treatment for your asthma. 

Some also point to marijuana smoke’s potential to negatively impact the lungs as a negative side effect. Animal studies suggest that cannabis smoking correlates to changes in lung cells and lung diseases like bronchiolitis. Still, a 20-year longitudinal study on smoked cannabis in humans found no evidence that it’s use correlates with increased lung disease or decreased pulmonary function. In fact, this research suggests that it may actually increase pulmonary function for some cannabis users. 

Since asthma can be a life-threatening condition, it is best to work with an MD who has experience treating asthma with marijuana, and can help assist with any negative side effects that might arise.