I'm not a doctor but I've had biliaray colic resulting from a hypoactive gallbladder (low functioning), with a 6% HIDAscan. I'm not 100% because I'm not a doctor but if you're having this problem from a low gallbladder function then I'm not so sure how well Bentyl would help and if anything it might make it worse. I say this because it slows the smooth muscles and if your problem is a low function then this could make it worse...or at least that's my theory for what it's worth.
What I do know for absolute certain is that if you have a hypoactive gallbladder (low function), you do not want to take an opioid, which Bentyl is not but in some ways can behave like. As it turned out for me my gallbladder problems were totally induced from using an opioid for pain management from something else. When I went to my doctor he prescribed me Lortab, which as it turned out was the worst thing he could have done for me. Then I looked online and saw the connection between opioid meds and low gallbladder function, I quit all opioids and my gallbladder function returned in a few months.