One of the common themes of the Hulk is the uneasy relationship between the big green guy and Bruce Banner. The Hulk is extremely useful when there’s a gigantic flying monster or mischievous Norse god to smash, but it can’t be fun knowing that stubbing your toe could result in you wiping out a city block. As such, the MCU Banner is usually wary of his destructive, angry alter ego.
Now, in a new official MCU tie-in book titled The Wakanda Files: A Technological Exploration of the Avengers and Beyond, we get an idea of the desperate ways Banner attempted to treat his condition. His notes show him zeroing in on the stress and elevated heart rate that causes him to Hulk out, theorizing that the right drugs might work.
“My recent work has yielded the creation of an anti-arrhythmic that slows my pulse to about a beat per minute. It struck me that with the right configuration, the cardiological potential of the drug might help soothe the stresses that incite Hulk incidents.”
Now, I’m not a doctor, but given that a healthy resting heart rate is between 60-100 BPM, I’m thinking that Banner’s anti-arrhythmic drug reducing his heart rate to 1 BPM would indeed be 100% successful in preventing the Hulk appearing, because it would kill him. The book goes on to unsurprisingly reveal that his research didn’t work, though the drug apparently was later used by Nick Fury to fake his death in Captain America: The Winter Soldier.
Still, being Bruce Banner doesn’t sound like much fun, with a note by Agent Coulson describing him after he reverts from his Hulk form as so:
“When Banner returns to his regular human state, he’s exhausted and requires rest… The metabolic shift in his system requires him to refuel.”
Of course, as we all saw in Avengers: Endgame, Banner found a way to deal with the Hulk that didn’t involve forcibly suppressing him. His evolution into Smart Hulk wasn’t seen in the movie itself, though director Joe Russo explained that the two reconciled as they felt that their adversarial setup got in the way of fighting Thanos.
“Banner reflects over that five year period about ‘The two of us have been fighting over this host body for years and we lost because we were fighting. It was selfish of us to fight over the host body.’ So the only natural progression forward for someone as intelligent as Banner to resolve the situation is ‘Let’s merge ourselves. Let’s quit fighting over the host body and just merge.'”
Right now, we don’t know when we’ll next see Ruffalo’s Hulk in action. The best bet is the Disney+ She-Hulk series, though, which will feature Banner’s cousin Jennifer Walters receiving a transfusion of his gamma-infused blood. There are rumors that Ruffalo has signed on for the show, but we haven’t heard anything concrete just yet.