



Published in the British Journal of Pharmacology , a new study shows marijuana may have a similar effect on the airways as some asthma medications.

Using samples of human lung tissue, French researchers found that THC could block muscle contractions caused by a signaling molecule called acetycholine.

Acetycholine is responsible for maintaining muscle tone of the airways and also contributes to contractions in asthma attacks. Interestingly, asthma medications block the same molecule, but from a slightly different angle.

“They prevent the acetycholine from binding to its receptor,” explains Dr. Donald Tashkin, who was not involved with the study. “But THC works proximal to that. It doesn’t have any competitive effect for binding to receptors. It just prevents the acetylcholine from being released.”

Dr. Donald Tashkin, a lung expert and professor of medicine at UCLA, was part of the team that first discovered marijuana’s effect as a bronchodilator. In 1973, his group published a study in the New England Journal of Medicine that found airways widen in both healthy and asthmatic individuals after smoking marijuana.

In fact, Dr. Tashkin’s findings led to a number of subsequent studies on delivering THC through an inhaler. But the inhaler route didn’t work, he says, because THC was too large of a molecule and caused patients to cough.





Taking THC orally was also tried, but its effect on the airways was delayed and too weak.





And while researchers eventually concluded that smoking was the best route of administration, smoking seemed like a poor choice for delivering a treatment.



