Numerous creators have expressed disappointment at the news that the horror title is ending in February, while others have criticised the publisher, predicting that the replacement comic will be heavily toned down.
Warren Ellis, who penned the title in 1999, wrote on Twitter: "Hellblazer cancelled, replaced by PG version. Sad to see that place for British horror stories go."
Scottish crime novelist Ian Rankin, whose only work in the comics field was a Constantine story for the Vertigo Crime imprint, predicted that the end of the series will lead to the demise of the character.
"Just heard Hellblazer comic book is for the chop. Only series I've ever written for. Only one I wanted to write for. Constantine RIP," he wrote.
Former 2000 AD editor Andy Diggle also paid tribute to the long-running series, crediting it with sparking his interest in comics.
"Desperately sad to hear that Hellblazer will be coming to an end after 300 issues. I cannot overstate the importance of that book, and the character of John Constantine, not only to my work but to my worldview," he said.
"I was lucky enough to write Hellblazer a few years back, and it was like meeting up with an old friend. I just knew him. I don't mean that in an arrogant way. Just that I'd been following him since his first appearance in Swamp Thing when I was 15 years old."
He added: "True fact: John Constantine is the reason I started reading [and eventually writing] American comics. Alan Moore's Swamp Thing led me to my first comic shop to hunt for back issues. F**k, I feel like I've lost an old friend."
Hellblazer #300, written by Peter Milligan with art from Giuseppe Camuncoli and Stefano Landini, arrives in stores in February, 2013.