Guess What? Smoking Pot, Meth Bad for your Asthma

So the last case of the morning yesterday was a 24 year old male in respiratory distress. He got duoneb breathing treatments and a magnesium drip in route and the paramedic was still coming code 3 so we knew he was struggling. The patient arrived drenched in sweat and pale with resps about 40 a minute. 
He looked sick and was wearing out.  The MD ordered BiPap for him, but he was barely tolerating the nebulizer mask. He had that hypoxic anxiety that is common in older COPD patients who feel like they are drowning and you just can't convince them that they are getting enough air even after you fix them. 
Yet this kid seemed to have something else going on too. We asked him if he had smoked. He nodded his head "yes" to smoking meth and pot over the past two days. 
He was too wound up to tolerate the BiPap mask and was getting increasingly agitated. His ABGs were horrible. We intubated him. 
The social worker came back from the family waiting room and said his girlfriend was out there and appeared to be tweaking on meth too. The social worker asked us about the effect of meth on the lungs - on top of asthma.  
"Well, they clean up meth labs in hazmat suits if that tells you anything," I said. "Smoking pot isn't good for your lungs either."
One of the ED techs was standing next to me and protested.
 "There's never been any study that has proven pot is bad for your lungs," she said.
 I get a lot of pot-apologists in the 20-30 year age range - after all their parents and grandparents often smoked in their presence and so I'm sure they've all been indoctrinated about the overkill warnings in Reefer Madness. In isolation, I agree that it is a much more benign drug than meth - or even alcohol for that matter. 
Yet her assertion that smoking pot was not harmful to the lungs of an asthmatic seemed pretty counterintuitive to me. Taking smoke into your lungs and holding it in as long as possible just seems like something an asthmatic wouldn't want to do. 
Moreover, I used to tell my oncology patients that if they needed marijuana to help their appetite, they should bake it rather than smoke it. I'd seen many cases where COPD exacerbations were set off by smoking pot.
Indeed, smoking pot rapidly accelerates the progression and development of some lung diseases. A 2008 study found that "the development of bullous lung disease occurs in marijuana smokers approximately 20 years earlier than tobacco smokers." Published in the journal Respirology, the authors found that CT scans revealed the progression of bullous lung disease in pot smokers. 

Patients who smoke marijuana inhale more and hold their breath four times longer than cigarette smokers. It is the breathing manoeuvres of marijuana smokers that serve to increase the concentration and pulmonary deposition of inhaled particulate matter – resulting in greater and more rapid lung destruction. Science Daily reported.

Moreover, other research has supported a significant increase in COPD development if a patient smokes pot and cigarettes -- a synergistic effect greater than either alone. Some studies indicate that exposure to pot smoke at a young age helps predispose patients to COPD development later in life. It certainly kills cilia and damages airways - which of course predispose repeated upper respiratory infections and chronic bronchitis.
Of course, it is hard to due randomized controlled trials on an illegal substance, even if that substance is the second most smoked product on the planet. As a 2009 review of the links between Pot and COPD concluded:

"Firm conclusions cannot be drawn about the association between use of marijuana and COPD based on the limited and inconsistent data available. The studies that address this topic are limited by their small numbers of participants and by the uncertain accuracy of self-reported use of marijuana, particularly in view of its illegality and the difficulty of accurately recalling amounts previously used. Nevertheless, the consistency of some aspects of the available data allows us to more firmly conclude that smoking marijuana by itself can lead to respiratory symptoms because of injurious effects of the smoke on larger airways."

Note the part there about the trouble with pot smokers having trouble remembering...
Marijuana has become more and more accepted in society and these days medical pot dispensaries are opening up faster than Starbucks stores. A few years ago it was estimated that  11 million people smoked marijuana during the last month, and approximately 20% of these smoke almost daily. These smokers -- even if they don't smoke tobacco -- report chronic bronchitis, frequent phlegm, shortness of breath, frequent wheezing, chest sounds without a cold, and pneumonia, according to a 2004 study. 
Moreover, other studies have found significant damage at the cellular level and may predispose patients for lung cancers. It disrupts the immune response in the lungs as well, predisposing patients to respiratory infections. 

"Regular marijuana smoking produces a number of long-term pulmonary consequences, including chronic cough and sputum, histopathologic evidence of widespread airway inflammation and injury and immunohistochemical evidence of dysregulated growth of respiratory epithelial cells, that may be precursors to lung cancer. The THC in marijuana could contribute to some of these injurious changes through its ability to augment oxidative stress, cause mitochondrial dysfunction, and inhibit apoptosis."

Another study found that pot delivers different doses and chemical changes compared to tobacco: Each joint delivered five times the increase in carboxyhemoglobin levels compared to tobacco. Toking delivers three times as much tar to the lungs versus smoking.
What about meth? Well there's pulmonary hypertension, but so far I didn't find a lot of controlled studies on it. It's a drug that has been around since 1919,  but has become wildly popular only in the last 20 years or so and so the research is more focused on the more obvious health effects.


So, if you have asthma don't smoke meth and don't think that pot is healthy just because you got a script for it.