Crested geckos are fun little pets to have. They are hardy and easy to handle even for new crested gecko owners.
However, they may not always be easy to read. Sometimes, as pet owners of crested geckos, you may need to be very observant.
One such case is when you observe your crested gecko keeping its mouth open randomly.
A crested gecko may open its mouth to express distress or feelings of threat. Sometimes, crested geckos open their mouths to regulate their temperatures.
There are many reasons why a crested gecko may be opening its mouth.
Why Your Crested Gecko Opens its Mouth?
There are many reasons why your crested gecko may be opening its mouth.
Regulating Body Temperature
Crested geckos are ectothermic. This means that a crested gecko depends on its environment to regulate its body temperature. If your crested gecko is too cold, it may open its mouth to warm up – and the reverse works as well.
So, if your crested gecko is opening its mouth for no apparent reason, you should check the temperature of the enclosure. Make sure that the temperature is in the ambient range.
Signs Of Distress
If your crested gecko is opening its mouth and panting, it could signify distress. Firstly, check the temperature and humidity of the enclosure.
If the parameters of the enclosure are fine, then check if it has something stuck in the mouth that it may be trying to remove. You may even consult your vet if your crested gecko shows additional signs of distress.
Feeling Threatened
Sometimes, when your crested gecko feels threatened, it may express that by opening its mouth. Crested geckos do this to try and intimidate whatever they are afraid of.
In this case, you must remove whatever is threatening your crested gecko.
Licking Its Eyes Or Face
Sometimes, while you may panic seeing your crested gecko open its mouth, chances are that it is just licking its face or eyes.
So, when your crested gecko opens its mouth, look closely and see if it’s simply licking its eyes and face.
Regurgitation
This happens when something gets stuck in the throat of your crested gecko while it’s eating. If you see something that you can easily grab and remove, then help your crested gecko out.
First, make sure that it is not stressed or panicked, and then using a pair of tweezers, remove whatever is stuck.
If you cannot remove it, then let it regurgitate on its own. While it is good that the crested gecko can regurgitate on its own, the process can be slow and uncomfortable and may take about 3 days to a week.
Stress Due To Handling
If you observe that your crested gecko opens its mouth whenever you approach its enclosure, but it closes its mouth when you’re at a distance, it might mean that you could be stressing it out.
Don’t worry – this is probably only because your crested gecko may be a new pet and needs some time to adjust to your presence and its new enclosure.
Crested geckos are solitary creatures. They need their own time and pace to get used to the presence of their new owners.

Initial Stress During Misting
As a crested gecko owner, you know that the enclosure of the crested gecko needs misting. When your crested gecko is new to the misting process, it will get stressed out and might open its mouth to express its stress.
You don’t need to worry about this – your crested gecko may eventually get used to this process.
However, even if it doesn’t, you can let this one slide as misting is essential to maintain the humidity in the enclosure.
Discomfort In The Current Enclosure Settings
Check the parameters of the enclosure of your crested gecko – the temperature, humidity, and lighting of the enclosure should be within the appropriate range.
If any of the parameters is off, it may cause your crested gecko to be stressed, and it may show that by opening its mouth.
Illness
If your crested gecko is opening its mouth along with some of these additional signs, then you should consult your vet to understand the root cause behind it and give your crested gecko the proper treatment it needs.
Additional symptoms:
- Lethargy
- Refusing to eat
- Soft jaw
- Soft bones
- Back kinking
- Tail kinking
- Inability to sleep
- Aggressiveness
Causes Of Crested Gecko Opening Its Mouth
The causes of your crested gecko opening its mouth could range from normal behavior to some serious sign of distress or illness. The following are the most common causes of your crested gecko opening its mouth:
- Licking its mouth or face
- Respiratory issues
- Regurgitation
- Temperature regulation
- Uncomfortable enclosure settings
- Underlying illness or medical condition
- Stress due to handling
- Stress due to misting
- Environmental or social stressors
- Feeling threatened
Is It A Sign Of Illness?
Your crested gecko opening its mouth could be a sign of illness or respiratory problems. When your crested gecko is opening its mouth, observe and check if you can see any additional symptoms, like:
- Lethargy
- Panting
- Restlessness
- Aggression
- Soft jaw and bones
- Kinking of back or tail
- Loss of appetite
If your crested gecko shows any of these signs along with opening its mouth, then it is advisable to consult a vet so that you can give your crested gecko proper treatment.

How To Prevent Your Crested Gecko From Opening Its Mouth
If your crested gecko is simply opening its mouth to lick its face or eyes, you don’t need to worry about preventing it from opening its mouth.
However, if your crested gecko opens its mouth due to other reasons such as stress or illness, then eliminating the root cause will help you prevent your crested gecko from opening its mouth.
For instance, if your crested gecko seems to be keeping its mouth open due to illness, then consult a vet and start its proper treatment right away.
As your crested gecko recovers, it will stop keeping its mouth open on its own.
The same goes for when it is stressed. Simply remove the factors that are causing the stress and your crested gecko should be fine.

Conclusion
There are many reasons why your crested gecko may open its mouth. While some reasons are worrisome and need your intervention, other reasons simply demonstrate the normal behavior of the crested gecko.
In either case, all you need to do first is simply observe and figure out why your crested gecko is opening its mouth.
You can help your crested gecko by removing stressors from its environment and regular checkups with the vet to ensure your crested gecko is healthy.