Structure of 1,8-cineole (eucalyptol)

Terpenes have been an interest of mine for the last few years. Many people seem to associate terpenes with cannabis, but they are ubiquitous across the plant kingdom. I see them as archetypal aromas, and am fascinated by the medicinal properties. For instance, beta-caryophyllene (which is found in e.g. in cloves, basil, black pepper, and copaiba) is a CB2-agonist – meaning that it has pretty much the exact same anti-inflammatory effects as CBD, without all the expensive hype. The first time I smelled pure beta-caryophyllene, it reminded me of old-fashioned candy, namely purple colored NECCO wafers and valentine hearts. I’m not 100% sure but it may be part of the flavoring of such. (Random factoid: the NECCO factory was next door to the MIT campus when I was there, and I could always tell which days they were manufacturing Tootsie Rolls.)

Another oil that is a potent anti-inflammatory is eucalyptus, the most active terpene being 1,8-cineole (aka eucalyptol).1 I always thought that internal ingestion of eucalyptol was toxic, but from sources I found it has been safely used in humans orally (IIRC dosages of 5-10 drops, consult your doctor blah blah) for chronic lung inflammation.

Due to their potency and ubiquity/low-cost, it would seem that terpenes could be valuable anti-inflammatory therapies against COVID-19. And in fact, I was not the only one with this idea. I first saw that a company in Israel was had a successful trial with their terpene blend to fight the COVID-19 cytokine storm.2 I also found a nice review on essential oils as possible therapy for COVID.3 Another article I found showed positive effects in vitro.4. This blend contains beta-caryophyllene, eucalyptol, and citral (part of the delicious flavor of Lemonhead candy).

Terpenes are magical chemicals that tickle our nose and tastebuds, and are also used as a universal communication device for fungi, plants and animals.