Is Smoking Weed Therapy? The Lung Trade-Off and THC's Two-Faced Dose

Smoking cannabis can deliver THC's therapeutic effects fast, but as therapy it comes with a catch: the smoke irritates and inflames your airways much like tobacco smoke does, and THC itself works differently at low and high doses. Humans have used cannabis as medicine and for fun for more than 10,000 years. The plant comes from Asia, and the earliest written references, from China and India, are often dated to around 2737 BC and credited to Shen Nung, a legendary Chinese emperor considered the father of Chinese medicine.

The ancient Egyptians recognized its medicinal properties too: the Ebers Papyrus is often cited as recommending it as a suppository for hemorrhoids. And some scholars read the “kaneh-bosm” in the holy anointing oil of the Book of Exodus as a reference to cannabis.

So when we talk about the benefits of weed, it's impossible not to talk about the different ways people use it as therapy.

Is it bad to smoke medical cannabis?

One of the most common ways people take cannabis is by inhaling it, usually in a hand-rolled joint.

But is that a good idea? Can you smoke medical cannabis? When it comes to the downsides, studies estimate that the amount of tar reaching the upper airways is about three times higher than with the smoke from commercial cigarettes.

On top of that, joints contain higher concentrations of benzanthracenes and benzopyrenes, which have been identified as carcinogens. People also tend to smoke a joint differently: puffs about a third bigger, a third deeper, and breath-holds about four times longer, all to get the most out of every hit.

Does burning weed at high temperatures hurt your airways?

Some researchers have argued that the higher temperature at which weed burns compared with tobacco may increase irritation of the mucous membranes. A hotter burn is one possible explanation.

Studies have also shown that cannabis smokers have significantly more bronchitis, with more frequent symptoms like wheezing and a productive cough.

Researchers have looked at other kinds of damage as well and found that smoking cannabis can affect the lining of the larger airways, causing swelling (edema) and redness (erythema). In one study of mucosal biopsies, goblet cell hyperplasia with increased mucus secretion, loss of the ciliated lining and squamous metaplasia were found in 97% of smokers.

Their conclusion: smoking weed is associated with chronic airway inflammation, with changes similar to those seen in regular tobacco smokers.

Weed vs. cigarettes: is there a difference for your lungs?

Research has concluded that lung complications in chronic weed smokers are comparable to those in chronic tobacco smokers. One estimate even puts 3 to 4 joints a day roughly on par with 20 cigarettes in terms of damage to the bronchial tissue.

How does THC work as medicine?

THC is known for producing cannabis's signature high by binding to CB1 receptors in the brain, which leads to a boost in dopamine.

Generally speaking, the more THC you take in, the more intense the high. Over the past few decades, breeders have focused on producing strains with more and more of this cannabinoid. Some of the effects of THC that users find beneficial include:

• Euphoria
• Creativity
• Increased appetite
• Relaxation

Several of these effects could help some users manage anxiety. But people who are new to weed or very sensitive to THC can end up with effects that crank their anxiety up instead, making it worse in both the short and long term. Some of the known downsides include:

• Anxiety
• Paranoia
• Confusion
• Short-term memory problems

How to use THC so it actually helps

With all that in mind, THC is a double-edged sword. Plenty of people feel noticeably calmer after smoking high-THC strains, while others find their symptoms get worse.

Some research also indicates that low doses of THC may help reduce anxiety, while high doses can make it worse. That's why the usual advice is to go for strains with low to moderate potency.

Luckily, to help people avoid the downsides, seed banks have started breeding strains with low THC and plenty of non-intoxicating cannabinoids like CBD.

The bottom line: should medical cannabis be smoked?

So far, ongoing research has found that THC has a biphasic dose response. Put simply, it does one thing at low doses and the opposite at high doses.

That's why, inconvenient as it is, the recommended approach is to try different doses and pay attention to how each one makes you feel: Do you feel euphoric? Relaxed? Confused or paranoid? Did your anxiety go down? All of this matters when you're figuring out the right dose for you. It comes down to careful trial and error, ideally with a doctor in the loop and starting low.

Psychedelic-assisted psychotherapy is also starting to gain ground, which hints at a future where cannabis could be used in a more professional therapy setting too. Right now there isn't much research on that. But as we said, start low, see how you feel, and you may find what works for you.