12 Iguana Diseases & How To Identify Them

do iguanas carry diseases

Like humans, iguanas can carry a whole host of diseases, some of which can be transmitted over to people. While herp veterinarians claim most iguanas’ medical problems are due to poor husbandry, some issues are, unfortunately, completely out of our control.

However, that doesn’t mean we shouldn’t become familiar with iguana diseases, as learning to recognize the symptoms can mean the difference between life and death for our scaly pets. In this post, I have taken the time to describe twelve of the most common iguana diseases as well as their symptoms.

Should you recognize symptoms from any of the following diseases, please take your iguana to the vet immediately.

1. Salmonella

Salmonella is a bacterium commonly found in the intestines and feces of reptiles and amphibians. However, you may have also heard about it from the CDC issuing warnings regarding eating uncooked chicken or eggs.

Although Salmonella cannot be completely eradicated from an iguana’s intestinal tract, the good news is the bacterium rarely poses a threat to the animal’s life. However, Salmonella is not to be regarded as innocuous.

Unfortunately for humans, Salmonella is a zoonotic disease, meaning it can be transmitted from animals to people, and can be especially dangerous for high-risk groups such as:

  • Very young children
  • Elderly
  • People with weakened immune systems
  • Pregnant women
  • People who are chronically ill

However, for most healthy adults, Salmonella poisoning usually results in vomiting and/or diarrhea at worst. On a more positive note, getting infected with Salmonella from reptiles is not common.

According to arav.org, cross-contamination can occur whenever you touch a surface that has been in contact with the iguana’s mouth or feces. Therefore, it is absolutely crucial that you wash your hands with soap and warm water after handling your iguana, its cage, or anything inside the cage.

Although most reptiles carry Salmonella, there is no way to be certain whether your iguana has contracted the bacterium simply by looking at it.

The only sure way to know is by taking a feces sample to the vet, and even then, according to James W. Hatfield in his book, Green Iguana The Ultimate Owner’s Manual, it may take several tests using different feces samples to obtain a definitive result.

The moral of the story is to wash your hands every time you handle your iguana or anything your iguana touches.

Check out this post I wrote about iguanas and salmonella to learn more.

2. Metabolic Bone Diseases (MBD)

Zowie shows us the kinks on her MBD surviving iguana

Metabolic Bone Disease, also known as Nutritional Secondary Hyperparathyroidism (NSHP), is a medical condition that occurs when an iguana fails to obtain adequate amounts of calcium, usually due to a lack of UV light exposure, but can also be linked to a calcium poor diet. Therefore, MBD tends to be an issue more so with captive iguanas, as their wild counterparts spend the majority of their day basking in the sun.

More specifically, MBD stems from a low calcium-to-phosphorus ratio, which should be roughly 2:1 and is regulated by Vitamin D.

Unfortunately, MBD is the most common medical condition among pet iguanas, as stated by two vets in Hatfield’s book. When an iguana is not getting enough calcium, its body tries to compensate by using the calcium in its bones, resulting in symptoms that are grotesque and painful for the animal. They include:

  • Loss of appetite
  • Weight loss
  • The condition known as rubber jaw, which involves a softening of the lizard’s jaw bone
  • Broken and brittle bones
  • Inability to climb
  • Swollen back legs
  • Tremors and twitching of the muscles
  • Dragging its body around
  • Crooked spine and/or tail
  • Seizures/convulsions
  • Death

Fortunately for the iguana, MBD can be reversed if detected early on. Therefore, make sure to take your iguana to the vet immediately after identifying any of the symptoms. Just remember to be extra careful when handling your iguana, as picking them up can result in broken bones, especially if the bones have become brittle.

Failure to address Metabolic Bone Disease will more than likely result in death or permanently stunting your iguana’s growth. The same applies to neglecting loss of appetite.

Check out a post I wrote regarding how long iguanas can live without food to grasp a better understanding of how detrimental this symptom can truly be.

Although MBD cannot be transmitted to humans, you should still wash your hands every time after handling your pet.

3. Parasite Worms

Parasite worms are actual worms that live inside the iguana and survive by leeching off the host’s blood supply and nutrients in the digestive system.

Iguanas can become infected with various types of worms such as:

  • Nematodes (roundworms)
  • Cestodes (pinworms)
  • Trematodes (flukes)
  • Tapeworms
  • Hookworms
  • Strongyles (blood worm)

Symptoms that your iguana may be infected with one or more of the aforementioned worms can include:

  • Loss of appetite
  • Weight loss
  • Lethargy
  • Pooping more frequently
  • Mucus in their feces
  • Actual worms in their feces

Worms are generally transmitted from one iguana to another, especially when coming in contact with worm-infected feces, but an unsanitary environment and/or unclean water may also be the cause of infection.

Therefore, it’s super important to constantly clean your iguana’s cage, especially if you know for sure it has been infected with worms.

Iguana expert James Hatfield urgently insists you take your iguana to the vet as soon as you adopt them. Since most iguanas at pet shops are kept in groups, getting infected with worms is likely to occur.

Screening for worms requires taking a feces sample to the vet for examination. However, be sure to give the vet a call before showing up with a pile of poop, as they will let you know how much to take.

If your iguana is indeed infected with worms, you will be given medication (most likely Ivermectin or Panacur), and the vet may inject your iguana with a vitamin shot to help with the loss of nutrients.

4. Parasite Bugs

Aside from worms, which dwell on the inside of an animal, iguanas can also become a host to bugs on the outside of its body. The two most common types of bugs are mites and ticks.

Interestingly enough, mites and ticks are not actually bugs, but arachnids, the same type of animal category as spiders.

Both of these animals survive by sucking the blood out of your iguana, which can cause a lot of distress to your little green friend.

Let’s go over ticks first.


Devine shows us an actual tick on an iguana

These little blood-sucking creatures have a beak-like mouths which they dig into your iguana to begin the feast.

However, ticks, like mites, need to reach a soft area on the iguana to be able to suck the blood out, such as under a scale, near the eyes, armpits, or nose. Once the tick is able to dig in, it will swell up many times its original body size, making it a little easier to spot.

If your iguana has ticks, you may notice symptoms such as:

  • Loss of appetite
  • Excessive scratching
  • Irregular shedding
  • Damaged scales
  • Anemia

Fortunately, getting rid of ticks simply requires carefully and slowly plucking them off your iguana (using a pair of tweezers may help).

Failure to do so slowly may detach the tick’s head from its body and leave it dug into the iguana’s skin, resulting in increased chances of infection.

Once the tick is removed, apply an antibacterial ointment onto the iguana’s part of the skin where the tick was removed.


Mites are similar to ticks, but they reproduce significantly faster and are much smaller. Hence, by the time you notice one mite, you’ll more than likely already have an infestation.

Like ticks, they live off of the host by sucking its blood either underneath a scale or in a soft area. If you have only one pet reptile, and it was mite free at the time of adoption, you’ll more than likely never have to worry about mites.

Mites usually come with your iguana at the time of adoption. Therefore, pay close attention before taking your scaly pet home.

Symptoms for mites are the same as ticks (mentioned in the previous section).

I actually had the misfortune of dealing with mites infesting my iguana, Rex shortly after adopting him. Sadly, by the time I noticed the first mite, there were dozens if not hundreds of them, especially underneath the substrate.

They were tiny with a pinkish color, and couldn’t have been bigger than the size of a grain of sand. I’m not even kidding when I say they made ants look big. It took me weeks of constantly cleaning his enclosure to get rid of them, but more on that topic in a bit.

The only successful way to get rid of mites involves manually and thoroughly cleaning the iguana’s cage. If even one pair of mites or their eggs are left alive, you can rest assured they will reproduce back into a major problem within a matter of days.

If the mites are allowed to turn into a severe issue, your iguana may require medical treatment. However, only your herp vet will know if such is the case.

An important note to keep in mind when cleaning your iguana’s cage is to avoid using the brand PineSol, as it’s known to produce respiratory problems. Courtesy of James Hatfield once again.

5. Mouth Rot

Mouth Rot, also known as Infectious Stomatitis, is a medical condition caused by bacteria that attacks an iguana’s oral cavity and results in inflammation of the tongue, gums, and inner lining of the mouth.

The bacteria can be contracted from:

  • Unclean conditions such as dirty water and/or substrate
  • Trauma such as cuts or scrapes in or around the mouth area
  • Compromised immune systems from malnutrition, pre-existing medical conditions, or high-stress levels
  • Improper temperature conditions

According to Hatfield, improper temperature and a poor diet are the two most common causes of mouth rot.

Symptoms of this ugly disease include a cheese-like substance forming around the gums of the iguana and/or a cotton-like substance inside the mouth.

Fortunately for our pet iguanas, mouth rot is relatively easy to cure. Once it’s been positively identified, you should take your iguana to the vet, where they will proceed by scrubbing the infected area in order to remove the cheese and cotton-like substances and apply a topical antibiotic.

The vet will provide you with further instructions regarding treatment.

Although mouth rot cannot directly kill an iguana, it can prevent the animal from eating, as chewing food will become painful, thus weakening the animal until the point of death.

6. Prolapse

Prolapse is a condition where an internal organ, such as an intestine, rectum, or hemipenes, falls outside of an iguana’s vent, usually the cloaca.

Although a prolapse is not a type of disease, I decided to include it in this post because it can be caused by a bacterial infection, similar to most diseases.

  • Cancer
  • Parasites
  • Constipation
  • Bacterial infection

You can recognize the symptoms of a prolapse based on the appearance; a soft tissue resembling raw meat protruding outside of the iguana’s body.

However, don’t confuse a male iguana’s hemipenes with a prolapse. Hemipenes are a male iguana’s two penises, which, according to James Hatfield, look like soft globs that come out while mating, during masturbation, and occasionally, defecating.

You’ll know the difference between hemipenes and prolapse because the hemipenes will revert back into the iguana’s cloaca within half an hour after intercourse, a few minutes after masturbation, and a few seconds after defecating, but I digress.

Regarding a prolapse, only a trained vet should reinsert an iguana’s soft tissue back where it belongs, as doing so incorrectly can lead to much worse consequences.

Additionally, prolapses are not uncommon with iguanas, and if quickly addressed, do not pose a threat to the animal’s life. If your iguana is suffering from a prolapse, keep the soft tissue wet with water to facilitate the process of reinsertion.

Male iguanas may suffer from hemipenes prolapses, but the same process is required to rectify the


This video shows what prolapse looks like in an iguana. I tried to add it here in this post, but apparently, it’s age restricted.

7. Cancer

Apparently, almost every kind of animal is susceptible to cancer, and iguanas are no exception. Fortunately, cancer in iguanas is more rare than in other species.

Types of cancer that can affect iguanas include:

  • Squamous cell carcinoma
  • Fibrosarcoma
  • Hemangiosarcoma

Cancer can attack an iguana’s organs, skin, and/or body parts, depending on the type of cancer.

Therefore, symptoms can significantly vary. If your iguana begins showing any of the following signs and you can’t seem to pinpoint what’s wrong with your pet, you may want to visit the vet for a checkup.

  • Irregular defecation
  • Difficulty breathing
  • Lethargy
  • Loss of appetite
  • Out-of-the-norm behaviors

Also, keep an eye out for lumps that may signify tumors. Spotting the tumor early on may make it possible for the vet to remove it via surgery, otherwise, traditional forms of cancer treatment such as chemotherapy or radiation may be required.

Regarding iguanas and cancer, the saying, “an ounce of prevention is worth a pound of cure,” couldn’t be any more true. Provide your iguana with a healthy and clean habitat, sufficient UVB lighting, and a proper diet to minimize its chances of getting cancer.

8. Respiratory Problems

Respiratory problems in iguanas involve any dysfunction regarding breathing. Symptoms are numerous and include the following:

  • Wheezing
  • Open mouth for extended periods
  • Struggling to properly breathe
  • Lethargy
  • Loss of appetite
  • Mucus in the mouth
  • Liquid discharge in the nose area

Remember that iguanas expel excessive salts by “sneezing” them out. However, expelled salts are not the same as mucous produced by respiratory problems.

Causes for respiratory problems can include:

  • Exposure to cold temperatures for extended periods (very common)
  • Very dry enclosure (can dry mucous membranes resulting in possible infection)
  • Very humid enclosure with little ventilation

If you suspect your iguana has a respiratory issue, consult your herp vet immediately, as respiratory problems can quickly worsen if left unchecked.

The vet may prescribe medication. However, regardless of what the vet prescribes, you may want to increase the cage temperature (assuming it’s too low), improve the ventilation, and ensure your scaly pet is drinking enough water, especially if you see it expelling mucous.

9. Gout

Gout is the equivalent of arthritis in humans, and just like arthritis, gout is usually caused by consuming too much high-protein food, resulting in a build-up of uric acid in the bloodstream, tissue, lungs, liver, and kidneys.

However, failure to drink sufficient water can also lead to gout.

As you probably already know, iguanas are herbivores. Although they can eat meat like mice, cat food, or human food, it doesn’t mean they actually should.

According to James Hatfield, feeding animal protein to your iguana puts them at risk of developing gout, which can leave your pet lizard with permanent pain and/or mobility loss.

Gout is easier to recognize than most medical conditions, as the iguana’s body parts become swollen. However, additional symptoms may include:

  • Swollen joints, fingers, and toes
  • Lethargy
  • Unhealthy/sickly appearance

Gout can be treated via medication and a change in your iguana’s diet, but in severe cases, surgery may be needed. The best way to avoid gout is by feeding your iguana a proper diet, which you can view in this diet and supplement guide.

10. Black Fungus Disease (Black Spot Disease)

Black fungus disease is a rare but highly contagious skin fungus that was primarily an issue with farm-bred hatchlings and juvenile iguanas.

The disease was most likely the cause of poor living conditions stemming from a lack of information on the part of the breeders, but since information is more readily accessible in today’s day and age, black fungus has almost entirely become a thing of the past.

However, it doesn’t hurt to become familiar with the disease, should it happen to your little green friend.

Black fungus disease symptoms include the following:

  • Black and dry skin
  • Flaky scales (may fall out)

If you suspect that your iguana might have become infected with black fungus disease, immediately apply Neosporin or topical anti-fungal medication.

Additionally, make sure your iguana’s cage is clean, dry, and warm. Expose your iguana to as much unfiltered sunlight as possible throughout the day.

11. Blister Disease (Vesicular Dermatitis)

According to James Hatfield, blister disease is a skin condition not unlike black fungus disease, but instead of resulting in flaky black scales, you get fluid-filled blisters similar to those in humans after a nasty sunburn.

The blisters can appear throughout the iguana’s body, including its tail, mouth, limbs, and cloaca and affect the lizard in the following ways:

  • Mood changes i.e. increased aggression
  • Increased stress
  • Lethargy
  • Appetite loss

If left untreated, these blisters can rupture and become ulcers, scabs, open wounds, lead to organ dysfunction and/or death, or other types of infections.

Just like black fungus, blister disease is also contagious. Hence, make sure to separate any iguanas living in the same cage immediately after suspecting one of them has contracted a skin disease.

The combination of wet and unclean living conditions is usually the cause of this terrible disease, specifically a virus known as Iguana Iridovirus (IIV), which belongs to the Iridoviridae family.

Therefore, reversing the problem will require cleaning your iguana’s cage and ensuring the temperature is set accordingly. However, taking your iguana to the herp vet for testing should be the top priority.

12. Cloacal Infection

A cloacal infection is caused by fungi, bacteria, or parasitic agents, similar to vaginal infections in women. Fortunately, this type of infection is rare.

The cloaca is an orifice in both male and female iguanas that is used to eliminate waste and for mating purposes.

Symptoms of a cloacal infection include:

  • Discharge
  • Swelling around or in the cloaca
  • Difficulty defecating and/or urinating
  • Appetite loss
  • Lethargy

If you believe your iguana may have a cloacal infection, the only remedy is to pay a visit to the vet. They will prescribe medication that you may have to personally give to your iguana over the course of a few days or weeks.

To prevent cloacal infections, keep your iguana’s enclosure clean and provide a healthy diet that will lead to a healthy immune system.


Phillip is the proud founder of Scaly Pets, a website dedicated to educating reptile pet owners. As a former owner of various reptiles, Phillip not only brings well researched topics to the table, but also years of personal experience. Now, he's sharing his passion with the rest of the world.

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