What Is The Green Stuff In Rick's Mouth On Rick & Morty? (2024)

Rick Sanchez routinely has some mysterious green stuff on his mouth throughout Rick and Morty, naturally raising questions as to what exactly the substance is. Adult Swim's Rick and Morty debuted in 2013 and has become a cultural phenomenon thanks to its creativity, characters, and goofy humor. Rick and Morty doesn’t shy away from heavier material either, with some of the animated sci-fi’s show’s most defining moments coming from surprisingly dark, serious story arcs like Rick’s backstory reveal in season 5's finale.

Rick's backstory shows how and why he gradually transformed into the acerbic, nihilistic genius scientist he is today. This process wasn't solely revealed in season 5, however, as Rick and Morty's previous seasons have also done a good job methodically revealing how Rick's gruff demeanor belies his tragic backstory and the still-lingering pain smoldering within. Even sillier moments in the show - like the Tiny Rick episode or Rick's "Wubba Lubba Dub Dub" catchphrase - are often revealed to have more somber ties to the pain Rick is in, meaning even minor details like the green stuff in Rick's mouth can hold weight in how the character is depicted as a whole.

Related: Rick & Morty Theory Makes Rick's Lab Coat A Plot Hole Solution

The Rick and Morty season 5 finale shows Rick started drinking heavily after his original family was killed, further emphasizing Rick's current state as something of a scientist, but also a severe alcoholic. Naturally, a common assumption is that the green stuff leaking from Rick's mouth is a result of his alcohol consumption. However, it could also be a running callback to something seeded in Rick and Morty's pilot episode. If the green stuff in Rick's mouth is a result of his alcoholism, it could be vomit or drool. Alcohol is a diuretic though, and studies show chronic alcohol consumption actually decreases saliva production which increases thirstiness and oral dryness. Vomiting is a medically recognized symptom of excessive alcohol consumption, though, so it's actually reasonably viable that the green stuff in Rick's mouth is a reflection of this, especially as the green stuff is often shown at a point where it's been suggested Rick has been heavily drinking.

Why The Green Stuff In Rick's Mouth Could Be Mega Seeds

Given this paints an even bleaker picture of Rick Sanchez in Rick and Morty, another somewhat less grim idea that holds weight is the theory that the green stuff in Rick's mouth could be some kind of residue or side effect from the mega seeds that were originally shown in Rick and Morty's pilot episode. Morty is shown with a similar viscous liquid oozing from his mouth after some mega seeds he was rectally smuggling dissolve inside him, imbuing him with temporary super-intelligence before temporarily hindering brain and motor functions. Rick was able to persuade his grandson into transporting them on his behalf in part because Rick has "done this too many times." With this in mind, extended exposure to the mega seeds could well leave a more permanent effect on the user, which supports the idea that the green stuff in Rick's mouth is in fact a symptom of his use of mega seeds.

As a sci-fi parody show, Rick and Morty goes out of its way to build wacky sci-fi narratives, but also makes sure to flesh out its characters at every available avenue, too. Therefore, it seems inevitable the green stuff in Rick's mouth could well eventually get explicitly addressed. It's a testament to Rick and Morty that this explanation has an equal likelihood of being either very serious, or very goofy.