Why is Your Bearded Dragon Changing Color to Yellow? YFD Explained

Bearded dragons have become increasingly popular as pets in recent years thanks mainly to their docile temperaments and relatively low maintenance compared to other reptiles, making them a good choice for first-time reptile owners.

Their ability to change colors quickly is also a very attractive trait to new exotic pet owners, although new owners quickly wonder what each color change means. So, let’s take yellow, for example.

What does a bearded dragon changing color to yellow mean?

Your Bearded dragon can change color to yellow for thermal regulation or to express their happy mood; however, a disease called Yellow Fungus also causes bearded dragons to show a yellow coloration, and its other symptoms include irregular shedding, restlessness, and strange behaviors.

There is a lot of debate surrounding this disease and whether there is a cure for it, but as with all other diseases, the quicker you can detect it, the better your pet’s survival chances will be. So, in this article, we are going to focus on Yellow Fungus and what you actually need to know about it.

For other colors, make sure to check out our complete guide to why bearded dragons change color and what each color means here.

Bearded Dragon Changing Color to Yellow Meaning

yellow beardie to answer Why is Your Bearded Dragon Changing Color to Yellow

Bearded dragons can change color to yellow for two reasons: as a way to regulate their body temperature and as a symptom of a disease called yellow fungus.

Yellow reflects more light and helps absorb more solar heat, which raises body temperature.

This color change is a natural and instinctive behavior that allows them to thermoregulate effectively and maintain a healthy body temperature.

We’ve discussed this further in our article on why do bearded dragons change color to orange.

However, if a bearded dragon’s yellow coloration is accompanied by other symptoms, such as lethargy, loss of appetite, and skin lesions, it may indicate yellow fungus, a potentially life-threatening fungal infection.

Because this disease is no laughing matter, we need to take any color change to yellow very seriously and treat it as if it’s caused by the disease until proven otherwise.

So, let me first give you a very quick piece of advice before you drop off and skip the rest of article (which you should not do, keep reading);

If your Beardie Changes color to yellow:
Take them to the vet right away. Better safe than sorry.

This is especially important if you are not the primary caregiver or have not been paying attention to them lately; either way, you are unsure if they have other symptoms.

Yellow Fungus in Bearded dragons

First off, what even if YFD? Well, Yellow fungus disease (YFD) is a type of skin infection that can affect bearded dragons.

It is caused by the Aspergillus flavus and Aspergillus fumigatus fungi and can lead to skin discoloration, swelling, and deformities. YFD can be serious if left untreated and can be challenging to cure, if it can be cured at all.


There are a few things that can cause Yellow Fungus Disease in Bearded dragons;

  1. Poor husbandry: Poor hygiene, overcrowding, and a damp and dirty environment can increase the risk of fungal infections, including YFD.
  2. Weak immune system: Bearded dragons with weakened immune systems, such as those that are malnourished or stressed, are more susceptible to YFD.
  3. Contaminated substrate: Fungi can grow in a contaminated substrate, such as soil or wood chips, and can be transmitted to reptiles through contact with the infected material.
  4. Contaminated food or water: Contaminated food or water can also spread the fungi that cause YFD.
  5. Ingestion of infected prey: Bearded dragons can become infected with YFD if they ingest insects or other prey that carry the fungi.


The symptoms of Yellow Fungus Disease (YFD) in bearded dragons can include:

  • Swelling of the skin or tissues
  • Lesions or scabs on the skin
  • Loss of appetite
  • Lethargy
  • Weight loss
  • Respiratory distress
  • Lameness or difficulty moving

Let’s quickly go over each of these symptoms

Swelling of the skin or tissues

Swelling of the skin or tissues is a common symptom of Yellow Fungus Disease (YFD) in beardies. The swelling can occur in any part of the body, but is most often seen in the limbs, neck, and head.

The swelling can be accompanied by discoloration of the affected areas, which may appear yellow or green.

The skin may also be hot to the touch and painful.

In severe cases or the late stages of the disease, the swelling can cause tissue damage, which can lead to difficulty breathing or moving, and in severe cases, it may even be life-threatening.

Lesions or scabs on the skin

Lesions or scabs on the skin are another common symptom of YFD in bearded dragons. These skin abnormalities can appear as raised, discolored patches or as crusty, scab-like formations. The skin may also be thickened and deformed in the areas affected.

Lesions or scabs may start small and then spread, causing significant damage to the skin and underlying tissue. In severe cases, YFD can cause deformities or disfigure the affected areas.

Loss of appetite

When a bearded dragon is affected by YFD, it may experience a decline in its overall health and energy level, which can reduce its interest in eating.

The infection can also cause pain or discomfort in the affected areas, further discouraging the reptile from eating.

In addition to YFD, other health problems, such as parasites, stress, or temperature imbalances, can also cause loss of appetite in bearded dragons, so a loss in appetite does not always equal yellow fungus, but it is a solid indication when accompanied by other symptoms such as the yellow discoloration.


When a bearded dragon is affected by YFD, the infection can cause a decline in overall health, reducing its energy and making it less active. Since it also eats less, it does not have as much energy as it usually does, so it makes sense it will not be very active.

Reptiles are also very energy conservative, so they are doubtful to expend energy by moving unnecessarily as other pets do. With even less energy to go around, they will be even more conservative with their energy expenditure.

The affected areas may also be painful or uncomfortable, further contributing to the reptile’s lethargy.

Weight loss

Weight loss in bearded dragons can often result from yellow fungus disease (YFD), which can reduce the reptile’s appetite and lead to weight loss.

It is important to monitor the weight of your bearded dragon and seek veterinary care if you notice significant or unexplained weight loss.

Respiratory distress

Respiratory distress refers to difficulties in breathing, which can be caused by inflammation or infection in the respiratory tract. This severe symptom can occur in bearded dragons with yellow fungus disease (YFD).

In bearded dragons with YFD, the fungus can invade the respiratory tract and cause severe inflammation, leading to respiratory distress.

Symptoms of respiratory distress in bearded dragons may include coughing, wheezing, rapid or shallow breathing, and open-mouth breathing.

Lameness or difficulty moving.

Lameness or difficulty moving is a common symptom of Yellow Fungus Disease (YFD) in bearded dragons.

This can occur as a result of the swelling and tissue damage caused by the disease, which can affect the ability of the affected limb to bear weight.

In some cases, the swelling may also affect the movement of the joints, making it difficult for the bearded dragon to walk or move normally.


The diagnosis of Yellow Fungus Disease (YFD) in bearded dragons typically involves a combination of physical examination, laboratory testing, and sometimes imaging studies.

During a physical examination, your vet will assess the bearded dragon for signs of YFD, such as swelling, skin lesions, and difficulty moving.

They may also take samples of affected tissues for laboratory testing, which can include:

  • Fungal culture: A sample of affected tissue is taken and placed in a special growth medium to see if the fungus that causes YFD can be cultured.
  • Histopathology: A small sample of affected tissue is taken and examined under a microscope to look for signs of YFD.
  • Polymerase chain reaction (PCR) testing: A sample of affected tissue is tested to see if DNA from the YFD-causing fungus is present.

Based on the results of these tests, the veterinarian can determine whether the bearded dragon has YFD and develop an appropriate treatment plan.

In some cases, imaging studies, such as X-rays or ultrasound, may be used to assess the disease’s extent and monitor response to treatment.


Treating Yellow Fungus Disease (YFD) in bearded dragons typically involves a combination of antifungal medications and supportive care.

The specific treatment plan will depend on the severity of the disease, the location and extent of the affected tissues, and the overall health of the bearded dragon.

Some common effective treatments for YFD include:

  • Antifungal medications: Antifungal drugs, such as itraconazole or terbinafine, are used to kill the fungus that causes YFD. These medications may be administered orally or topically, depending on the severity of the disease.
  • Surgical removal of affected tissues: In some cases, surgery may be needed to remove severely affected tissues. This can help to reduce the spread of the disease and to prevent the development of serious complications.
  • Wound care: In cases where there are open wounds or skin lesions, proper wound care is important to promote healing and prevent infection.
  • Supportive care: In addition to antifungal treatment, supportive care is important to help the bearded dragon recover from YFD. This may include providing a warm and clean environment, ensuring proper nutrition and hydration, and providing pain management.

Can YFD Be Cured?

This is a very controversial point in the world of beardie owners, so let’s try to be scientific here. There is no scientific evidence that it can be cured, but it can be treated and handled almost to the point of being cured if caught early and treated promptly.

YFD can be challenging to handle, but with prompt and appropriate treatment, it is possible to manage the disease and prevent it from progressing.

The specific outcome will depend on several factors, including the severity of the disease, the location and extent of the affected tissues, and the overall health of the bearded dragon.

Treatment typically involves a combination of antifungal medications and supportive care. Antifungal drugs are used to kill the fungus that causes YFD, and supportive care is important to help the bearded dragon recover from the disease.

In some cases, surgical removal of affected tissues may be necessary to reduce the spread of the disease and prevent serious complications.


The best way to prevent (or at least minimize the chances of your beardie getting) Yellow Fungus Disease (YFD) is to give them the best life you could by maintaining good hygiene and minimizing the risk of exposure to the fungus that causes the disease.

Some steps that you can take to prevent YFD include:

  • Quarantine new animals: Before introducing new bearded dragons to your collection, it is important to quarantine them for at least 30 days to minimize the risk of spreading YFD or other diseases.
  • Practice good hygiene: Regularly clean and disinfect your bearded dragon’s cage, as well as any food and water dishes, toys, and other items that come into contact with your pet. Wash your hands thoroughly after handling your bearded dragon, and avoid touching your face or mouth while handling reptiles.
  • Minimize stress: Stress can weaken the immune system and make your bearded dragon susceptible to YFD and other diseases. Provide your bearded dragon with a warm and comfortable environment, and avoid excessively handling or disturbing your pet.
  • Regular veterinary check-ups: Regular veterinary check-ups can help to identify and treat YFD or other health problems early before they become more serious.

Can humans catch Yellow Fungus Disease from Bearded Dragons?

Don’t Worry, humans cannot catch Yellow Fungus Disease from Bearded Dragons. The disease affects reptiles, not humans. However, it is important to practice good hygiene when handling any pet, including beardies, to minimize the risk of infection.

Can you use antifungal creams for bearded dragons?

This will come as a surprise to many, but Yes!, antifungal creams can be used for bearded dragons, but it is important to seek veterinary guidance before using any medication on your pet.

Different antifungal creams have different active ingredients, and not all of them may be appropriate or effective for treating Yellow Fungus Disease (YFD) in bearded dragons.

Your veterinarian will be able to recommend the most appropriate antifungal cream based on the severity of the disease and other factors, such as the location of the affected tissues, the overall health of the bearded dragon, and any other medical conditions that may be present.

In some cases, topical antifungal creams may be used in conjunction with other treatments, such as oral antifungal medications or surgical removal of affected tissues.


In summary, YFD is a very serious health problem that affects bearded dragons, but with proper care and management, it is possible to manage the disease and prevent it from developing into something worse.

I hope you found it helpful! If you did, please share it or pin it!

Similar Posts