Noticing signs of illness in a lizard can be quite challenging. Their quiet demeanour and often limited frequency of handling mean that subtle problems can be easily missed. Many conditions are slow to develop, making gradual changes more difficult to spot. First-time lizard owners or those keeping a species that they are unfamiliar with may also mistake normal physiological changes for signs of disease. 

One of the most popular pet species of lizard in the UK is the leopard gecko. When cared for correctly this lizard species can do well in captivity. They can provide many years of companionship to a dedicated owner. However, incorrect husbandry is a major cause of illness in this species. So thorough research into their care requirements is vital.

General signs of illness include:

  • Reduced activity or lethargy
  • Poor appetite
  • Sunken eyes
  • Weight loss

Weight loss in leopard geckos can be assessed by observing the tail. The tail is used as a fat store which is depleted in the early stages of weight loss. Becoming thin and stick-like in comparison to the substantial, bulbous tail of a healthy leopard gecko. Weighing pet geckos weekly can bring attention to potential problems before other signs become apparent.

Shedding problems

Abnormal skin shedding (‘dysecdysis’) is a common reason for geckos to be presented to a vet. Dysecdysis in geckos commonly affects the skin around the toes, involving bands of skin which constrict the digits. This can lead to digit loss or even require amputation. Checking the toes regularly especially during a shed enables your vet to help as quickly as possible, Thus reducing the risk of digit loss. 

Dysecdysis can be prevented with appropriate husbandry. Taking particular care to ensure that the relative humidity of the enclosure is correct for the species. 40-60% for a leopard gecko. This is monitored using a hygrometer. Humidity can be modified by placing a shallow water dish in the enclosure which will evaporate in the warmth. A moist hide area such as a small cave lined with damp moss substrate should be also provided to aid shedding.

Correcting vitamin A deficiency can help to promote a healthy shed. Vitamin A is important for the healthy functioning of the immune system and mucous membranes such as the eyes, mouth, respiratory system and genitals. A deficiency in vitamin A can leave geckos vulnerable to infection at these sites as well as affecting the quality of their skin shed and can be corrected by dietary supplementation. 

Metabolic Bone Disease

Metabolic bone disease (MBD) is a condition caused by calcium and vitamin D3 deficiencies, resulting in bone deformities and weakness. Leopard geckos have limited UVB exposure in their natural habitat as they are mainly active at dawn and dusk. They do however benefit from exposure to low-intensity UVB light and are susceptible to developing MBD if this is not provided. 

Providing low-intensity UVB light and ensuring adequate calcium and vitamin D3 supplementation helps to prevent this condition and treat mild cases. Sadly, advanced cases often necessitate euthanasia, especially where severe deformities or bone fractures are present.

Tail loss

Leopard geckos exhibit tail autotomy, or ‘tail drop’, when threatened. This means that they can actively shed their tail as a defence mechanism. It is important to avoid handling geckos by the tail to prevent this. When shed, the tail does eventually re-grow with cartilage in place of the original bony vertebrae. The stump must be kept clean during the healing process to avoid infection. 


Intestinal parasites can lead to poor growth, failure to thrive, weight loss, inappetence and diarrhoea. Some parasites are considered normal in low numbers and do not cause illness. However others can be detrimental to the health of the gecko. 

Cryptosporidia is a protozoal parasite which can cause significant weight loss, diarrhoea and poor growth. This parasite is highly infectious to other geckos and difficult to treat, often resulting in euthanasia of unwell individuals. 


Gout is an accumulation of uric acid which precipitates as crystals within the organs (visceral gout) or the joints (articular gout). This produces a variety of symptoms depending on which areas of the body are affected. This painful condition is often related to chronic dehydration from insufficient humidity or water provision, low environmental temperatures, excessive protein in the diet or kidney disease. Changes in husbandry or specific treatments are required to correct this condition and severe cases may warrant euthanasia. 

Egg binding

Dystocia or ‘egg binding’ occurs when a female leopard gecko is struggling to pass her eggs. Females can lay eggs without the presence of a male, meaning that this condition can occur whether the individual is housed alone or with others. Lack of a suitable nesting area in the form of a moist hide is a significant risk for egg binding in this species. Adequate dietary calcium and vitamin D3, providing low-intensity UVB light and placing a moist hide within the enclosure can help to prevent and address mild cases. More severe cases or those ongoing for over 48 hours require veterinary intervention. This may involve hormone injections, supportive care, aspiration of the contents of the egg to make it smaller and easier to pass or surgery to remove the eggs. In some cases, vent prolapse can occur due to straining and these geckos should also receive veterinary attention. 

Gut impaction

Gut blockages are common in young leopard geckos. Most are due to provision of an inappropriate substrate such as bark or wood shavings. These may be ingested during feeding or when the gecko ‘smells’ the environment with their tongue. Signs of impaction may include loss of appetite, reduced activity, swelling of the abdomen and vent prolapse. Dehydration due to inadequate fluid intake, lack of a moist hide or insufficient environmental humidity also contributes to gut impaction. Treatment depends on the severity of the condition, with mild cases often responding to rehydration and husbandry changes. More severe cases require surgery to relieve the impaction.

Thermal burns

Burns from heat sources can cause skin damage, muscle damage and in severe cases even damage to the internal organs with full-thickness thermal burns. Reptiles are ectothermic, meaning that they are unable to regulate their own body temperature, instead relying on external sources of warmth within their environment. Heat sources that come into direct contact with the gecko such as heated rocks or exposed heat mats pose the greatest risk. Placing heat mats on the underside of the vivarium rather than on the inside creates a safe, warm area allowing heat to conduct through the floor of the enclosure and the substrate whilst shielding the gecko from direct contact with the heat source. Thermostats should be used to prevent over-heating of heat sources.

If something doesn’t seem right with your leopard gecko it is best to check with your vet. Subtle changes in behaviour, appetite or appearance may seem trivial but could indicate early stages of disease which, if addressed promptly, may be prevented from progressing. It is sensible to consider a veterinary consultation to discuss any concerns, as this provides the opportunity to discuss care requirements for the species and to compare recommendations with your current set-up, as well as enabling your pet to be checked over for assessment of general health.