Wikipedia's description of a tokay bite

The Tokay is also considered the "pit bull" of the Gecko world due to the fact that when they bite their human handlers, they often won't let go for up to several hours at a time, and generally cannot be forcibly removed without causing harm to the Gecko. One way of getting a Tokay to release its hold is to submerge the animal in water, which will encourage the lizard to let go, without causing it any harm or undue stress
Yeah, OW.