Are Iguanas Dangerous? The Essential Guide For Owners

iguana on branch

One of the first and most important questions that many people have before they buy a pet is are they dangerous. This is perhaps more so with iguanas than many other lizards, as they are bigger, and have been involved in a handful of injuries that have made the world’s press. Are iguanas dangerous?

Iguanas are not a very dangerous animal, but they should be treated with respect, knowledge and caution. They do sometimes bite, and the power of their jaws and serrated teeth can cause quite deep cuts. However, if they are handled well, most iguana owners will never encounter a problem.

It is therefore crucial to weigh up the pros and cons of having a pet iguana in your house before you buy one, particularly if they are going to be near young children. However, as I have said, most owners will never encounter any issues, and with some basic knowledge and understanding, you can react to any situations that may crop up and resolve them accordingly.

Can Iguanas Be Dangerous? The Facts

Iguanas are one of the largest lizards that are commonly kept as pets, and this comes with some issues. All lizards can bite, but the bite of a very small gecko is no more than a nip and is highly unlikely to even break the skin. The bite of an iguana is a very different story.

There are several physical dangers that it is important to be aware of:

  1. 120 sharp teeth. Iguanas have triangular razor-like teeth, which they use to tear their food. Like many lizards, they do not use their teeth to chew, but rather swallow their food whole. These teeth are sharp, and can leave deep flesh laceration-style wounds.
  2. Sharp claws. Their teeth are their most potent weapon, but iguanas also have sharp claws that they can use to strike and slash.
  3. Pushing and shoving. This is much less of a threat to humans, but it is one way that an iguana might attack in the wild.
  4. They have venom in their bite. Luckily this is harmless to humans, but it perhaps just something to be aware of.

When humans have been bitten by iguanas, the injury is normally to the fingers, hand, wrist, arm, ankle, or face. Some serious face injuries have been recorded in papers round the globe, but these really are exceptional circumstances.

It is important to understand that iguanas are regarded almost universally as a friendly and amiable pet.

They are relaxed and are not naturally aggressive at all. Their main response to danger is flight or hiding, rather than fighting.

If treated well, you may well never see any of the weapons they have in their armoury in an emergency.

Tame, win trust and learn to read their body language, and you will almost certainly be fine.

The Reasons Behind Aggressive Iguana Behavior

Iguanas are effected by a range of psychological forces and underpinning patterns of instinct that dictate how they behave. Often iguanas do not react in the same way to things from one day to the next, and there are often good reasons.

Some of the main reasons that an iguana may be angry, stressed or nervous are the following:

  1. They are territorial – Some iguanas seem to possess this instinct more strongly than others. They may not like humans entering their space and react aggressively.
  2. There is an alpha male streak of dominance – Males are generally more aggressive than females. Also larger males are usually more angry than smaller males. This alpha male desire for dominance can exert itself in displays of aggression.
  3. They are hormonal – Some iguanas are different from one day to the next. Hormonal changes are probably responsible for this
  4. They can be in an angry state of mind – Sometimes your iguana might just be in a grump! Look out for the signs, and just leave them be for a bit.
  5. Out of season – Both male and female iguanas have a specific season when they breed. In the wild this is thirty days, but in captivity it is often longer. When they are out of season they may be hormonal, or slightly out of sorts sometimes. It is just another thing to be aware of.
iguana lain on tree

Precautions Iguana Owners Can Take

There are several pro-active steps that iguana owners can take to make the experience of owning and handling your pet as safe as possible for everyone.

One idea is to clip their nails. This will just take the danger of being clawed out of the equation.

Another idea is to invest in some falconry gloves. These are a great buy, and can protect you against both scratches and even bites. These are great for developing the confidence of children in handling iguanas without fear.

The main precaution that you need to take is to understand your iguana’s body language. When you have a clear picture of that, and know any possible signs of aggression to look out for, then you are equipped to act if any of these signs are displayed.

Warning Signs They Might Attack

There are many signs to look out for that an iguana might be about to bite. If you see any of these, then just leave the iguana be:

  1. Standing on all fours – Like many animals they attempt to appear larger when under threat
  2. Bobbing its head – This is a key indicator. The iguana will bob their head up and down in a repeated action. This can happen fast, or more slowly.
  3. Hissing – This is a common aggressive behavior of many lizards. It is a similar response to a hissing cat. Stay well away
  4. Puff up its body – This is another way of trying to appear larger than they are. They breathe in deeply, and puff their body up with air.
  5. The lowering of the flap of skin under its chin – This is called the dewlap. This is behavior that is distinctive of iguanas.

Some iguana owners have reported that unfortunately sometimes they will bite without any warning, but this is unusual.

Almost always there will be at least one of these signs present, and sometimes a combination of a few. These signals demonstrate that the iguana feels under threat and may be about to act to resolve this.

Other Confrontational Iguana Behaviors

In the wild, when scared by predators, iguanas will normally resort to fleeing. If they are near water, they often chose this as a place to go, swimming to safety.

Although iguanas normally take flight as the first option, if they are injured they apparently prefer to stand and fight. An injured iguana will bite, claw and flick with its tail at whatever threat is in front of it.

When First Getting An Iguana

Be aware that for the first few days when a new iguana is in your house, the animal may be stressed by the whole shipping process. Moving habitats is a big transition, and will take some getting used to.

Please be aware that if you get your iguana from anywhere other than a pet shop, it may also have been open to some traumas. Some people buy iguanas from refuge homes. This is a great thing to do, but please be aware that the iguana may have been neglected or worse.

Most iguanas are quite docile to start with as they get used to their surroundings. Some may suddenly get a bit aggressive after a few days, though this often will not happen.

How To Tame An Iguana

It is recommended that you allow your pet iguana to have arrived in your house for two weeks before you start the taming process. This gives them time to get used to their new home.

Setting up a predictable routine is one of the most important parts of taming an iguana. Try to feed it at the same times, and with the same frequency. Interact with it at similar parts of the day, and for a similar time-length. Routine leads to a feeling of understanding and feeling relaxed in the habitat.

Talk to your iguana! This really does help. The more you talk, the more it becomes aware of you and what you are like.

Handle them gently but try to remain in charge. It needs to know that you are not a threat in any way, but at the same time you are dominant and it cannot control you.

Any signs of aggression then put them back, but don’t give up!


Iguanas are large lizards and so do have the potential to administer serious bites and other injuries. However, with the correct knowledge and handling procedures, the chances of them being aggressive it greatly reduced. Iguanas are known as a relaxed and friendly pet, and the likelihood of any injuries is very low in the right hands.

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