In the more than 150 years that Gila monsters have been known to science, there is no reliable account of a human fatality. Although not considered life threatening, a bite should be considered a medical emergency and should obviously be avoided. If proper care and judgment is exercised, a bite is something that should never happen.
Although the bite of a Gila monster won’t kill you, it may make you wish you were dead! It is very painful. The biggest threat of a bite comes from the fact that the typical adult Gila is a very calm and docile animal—it would be very easy to become complacent handling them. Never put yourself in a position where a bite could occur, no matter how much trust and familiarity you have with your animals. Perhaps the general calm nature of adult Gilas in captivity is related to the fact that they have few if any regular predators in the wild.
Gilas of all sizes can safely be handled using a pair of heavy leather gloves. Since Gilas don’t have the hollow fangs of front-fanged venomous snakes, even if their teeth could penetrate the leather, nearly all of the venom would be absorbed by the glove. Experienced Gila keepers frequently handle them without the aid of gloves. With proper experience and care this can be done safely. They are gently, but securely grasped around the neck in a way to restrict the lateral movement of their head. Their body weight can then be supported with the other hand. Gilas are very strong animals and are capable of quick and powerful lateral biting movements—a careful and secure grip is important. I always recommend that all handling of your Gilas be accomplished wearing appropriate leather gloves as protection.
Just as the typical adult Gila is a calm and docile animal, the typical young Gila is quite snappy. I would call it more defensive than aggressive. This is perhaps due to the fact that small Gilas are easier prey to a number of predators than are their adult counterparts. Due to their small size and attitude, hatchling and young Gilas are more difficult to handle. Not only are they more likely to bite, but in a six inch lizard the part you grab is much closer to the part that bites! Even so, they can very easily be handled with the before mentioned gloves.
I recommend that Gilas not be regularly handled except for husbandry needs. This is both for safety reasons as well as for the welfare of the animals.