Metabolic Bone Disease in Crested Geckos is a worry for all keepers.
Some keepers are concerned about their Gecko’s appearance or behavior. They may ask, “Why is my gecko having trouble climbing or walking?” Unfortunately, the answer is often metabolic bone disease.
Other keepers approach this disease from a different direction. They may have noticed that their gecko’s tail bends forward when hanging upside down on the glass. Some might feel a slight tremble every now when holding their pet.
The situation with MBD can be complicated, as symptoms in the early stages are hard to detect. Keep reading as we share what you need to know.
Article Contents
Key Points
- Metabolic Bone Disease happens when Crested Geckos are not provided with the the correct mix of calcium, phosphorus and vitamin D3.
- Their bones become soft and their skeleton too weak to carry out its normal functions, like eating, and moving or climbing.
- Signs of MBD in the early stages are hard to detect. They include lethargy, trembling, tendency to shake the head, difficulty eating (due to softening of the jaw), and some difficulty climbing.
- In more advanced stages, the gecko will have soft and floppy limbs, a mis-aligned jaw, a kinked spine (sometimes), and will have extreme difficulty climbing and moving.
- While the symptoms may be reversed in the early stages, they often aren’t reversible in more advanced stages, though further deterioration can be prevented.
- Metabolic Bone Disease is treated initially by providing the right amount of calcium and vitamin D3 in their diet. In severe cases, calcium and D3 may need to be provided in liquid form or by injection from a reptile vet.
Metabolic Bone Disease in Crested Geckos
Metabolic Bone Disease (MBD) is a health condition which happens when Crested Geckos are not provided with the the correct mix of calcium, phosphorus and vitamin D3. It is often caused by a lack of calcium in their diet which results in their bones becoming soft and “bendy”.
Crested Geckos need calcium to keep their bones strong so they can move and carry out bodily functions like eating, walking and climbing.
Without the right mix of calcium, phosphorus and vitamin D3, a Crested Gecko’s bones will not have enough usable calcium to remain strong.
At this point, their bones become deformed and wavy and begin to bend. They also won’t be able to move and eat properly, due to softening of their jaw and limbs.
This is called “metabolic bone disease” (MBD).
In a recent Reptiles Magazine article, Dr. Douglas Mader shared that there are actually a number of different types of metabolic bone disease, not just one! The type most keepers are worried about is more properly called “nutritional metabolic bone disease”.
Causes
Metabolic Bone Disease in Crested Geckos is caused when the balance of calcium, vitamin D3 and phosphorus is not correct. It happens most often when a Crested Gecko’s diet and supplementation is wrong.
All reptiles need calcium and then vitamin D3 so their bodies can metabolize (use) the calcium.
Minerals, primarily phosphorus, reduce their ability to metabolize calcium.
The balance of calcium, vitamin D3 and phosphorus in their diet is critical.
Most live feeder insects have a high phosphorus content. Ideally, the ratio of calcium to phosphorus should be 2:1. Since this is not the case with most feeders, additional calcium must be provided by dusting insects with a calcium and vitamin D3 supplement.
A Crested Gecko that eats a lot of live prey that isn’t dusted with calcium and vitamin D3 may eat too much phosphorus which will reduce their calcium absorption.

Author Tip: If a keeper feeds a homemade diet, it is important that calcium and vitamin D3 is supplemented. Some keepers make the mistake of supplementing with calcium, but neglect the vitamin D3.
Reptiles can get vitamin D3 from either UVB lighting or powdered supplements.
Keepers who would like to provide vitamin D3 through UVB should be aware of several important factors.
If your Crested Gecko spends many daylight hours inside a hide, or wrapped in leaves, it may not absorb much vitamin D3 from the light. Also, the amount of UVB radiation from fluorescent lighting decreases over time and may be insufficient after six months.
Stages
There are no official stages of MBD in Crested Geckos.
Instead, there is a more general description of three stages with a list of possible symptoms for each.
Early
The signs of early MBD are subtle and may often be missed or mistaken for a different health problem.
Symptoms include:
- Shakiness of the head and body when being handled
- Lethargy
- Reduced appetite
- Difficulty sticking to vertical surfaces
Moderate
By the time the moderate stage is reached, the gecko has obvious symptoms of MBD:
- Softening of bones
- Altered jaw (underbite or overbite)
- Swollen, bowed, kinked or bent spine and limbs
- Inability to eat
- Inability to climb
- Significant lethargy
- Gray or absent calcium sacs
Author Tip: One way to determine whether Crested Geckos have enough calcium reserves is to check the calcium sacs in their mouths. If these are gray or absent, instead of full and white, they may be lacking.
Severe
At this stage the gecko is in obvious distress and has great difficulty moving or eating. They will also have multiple deformities and would be considered to be severely ill, even by non-reptile keepers.
Symptoms
The symptoms of metabolic bone disease in Crested Geckos from earliest to most advanced include:
- Shakiness and trembling when trying to move
- Lethargy
- Decreased appetite
- Noticeable deformities in spine
- Wavy, kinked, swollen or bowed spine and extremities
- Misaligned jaw or mouth hanging open
- Absent or gray calcium sacs in the mouth
- Unable to stick to vertical surfaces
- Unable to climb or walk at all
MBD can also cause deformities in the Crested Gecko’s tail; however, there are other health conditions where the tail may look wavy or floppy (e.g. hatchling development and floppy tail syndrome).
Crested geckos that eat too much calcium and vitamin D3 can develop hypercalcemia which has similar symptoms.
Diagnosis
A reptile vet will diagnose Crested Gecko metabolic bone disease through a combination of blood tests and x-rays.
The blood test will determine if the calcium levels are adequate and an x-ray will check for deformed or fractured bones. They will also pair this information with a detailed history about the gecko’s care, diet, supplements and symptoms.
Without a visit to a vet, MBD can be only conditionally diagnosed through the observation of symptoms.
Treatment

If a keeper suspects metabolic bone disease and it is still in the early stages, the most important and effective treatment is to ensure that the gecko is receiving an optimal amount of calcium and vitamin D3.
I have found the easiest way to do this is to immediately start feeding a “complete” diet and dusting feeders consistently with calcium and vitamin D3. You can also add a UVB light in the enclosure, if you haven’t already.
Mild cases, if treated promptly, can resolve completely.
I am happy to say that I have never owned a Crested Gecko with metabolic bone disease, but I have adopted some Gargoyle Geckos with early MBD. In all cases, they became symptom free within a few months after a diet correction.

If the diet already appears to be correct, an appointment with a vet is recommended.
For more serious cases, where there are visible deformities and poor feeding and mobility, the progression can often be stopped by a visit to a reptile vet. The gecko may need to be provided with calcium through intravenous administration to supply an initial larger dose.
In order not to induce mineralization, intravenous fluid therapy is preferable. Do not resort to administering injections of calcium at home to a Crested Gecko with MBD.Dr. Jerry Ayaebi (DVM) – More Reptiles
Care
Many Crested Geckos can live comfortably with deformities from metabolic bone disease after the supplementation or diet has been fixed.
In some cases special tank adaptations may need to be made to make sure they have a good quality of life. Some are unable to climb smooth surfaces like glass walls, or to hold themselves up on vertical surfaces. An enclosure that uses cork bark and has ramp-like climbing paths may be best for these geckos (pictured below).

Crested geckos whose jaws have been significantly affected may have difficulty catching and eating live prey. They may benefit from a complete crested gecko diet that includes powdered insects.
Euthanasia is probably the best intervention for geckos with severe deformities, who are unable to move from the bottom of the enclosure and unable to eat. These geckos have a poor quality of life and will likely die a lingering and possibly painful death.
Any Crested Gecko can suffer from MBD without the right supplementation, but the disease is particularly hard on hatchlings and egg-laying females.
Hatchlings are producing bone at an increased rate as they quickly grow to adult size. The effect of reduced calcium on these developing bones is much more catastrophic than in adults and will be visible much sooner in the form of kinked and bent limbs and spine.
Females use valuable calcium resources when producing eggs. The eggs themselves, when laid by a female who is calcium deficient, will have soft or translucent shells. In advanced cases, the female may not have enough strength to lay the eggs and will have a much more rapid development of symptoms as the calcium is being quickly depleted.