Professional Herpetoculture for the Pet Trade

Diseases of Reptiles


At VMS, we frequently get inquiries regarding various health aspects of reptile keeping, especially inquiries about what to do with a sick specimen. The answer to all these questions is simple: "Take the animal to a qualified veterinarian". I cannot believe how many keepers will get information from forums, chat-rooms and websites about how to treat a sick reptile and consider it accurate. Is this where you would turn if your child suddenly began to vomit blood? Certainly not, so why go there when your reptile suddenly does? Besides, almost every ailment will require medication, and a veterinarian will be required to prescribe it. So in the end, you must go there anyway!

All that said, I do believe at least a basic overview and understanding of the various types of diseases which commonly affect captive reptiles is of immense value. Hopefully, the information presented here will assist the keeper in recognizing, or better yet preventing, most problems.

Infectious Diseases

Infectious diseases are caused by microscopic organisms which enter the host through various mechanisms and reproduce. They are easily transmitted from host to host and attention to hygiene practices is required to prevent spread. They commonly fall into several groups:

  • Fungi - As a rule, fungal infections require one key component to develop - a moist environment. The most commonly seen fungal infections involve blistering, discoloring or damage to skin and scales surfaces. Most are located on the ventral surfaces where the skin has been in contact with moist or soiled substrate for prolonged periods. A simple rule of thumb to prevent these problems is to keep substrates clean and dry. For specimens requiring damp substrates, remember to change it frequently to prevent fungal growth from developing. Occasionally, myco-fungi may also attack the soft surfaces of the lungs. This is most commonly seen in large boas and pythons which have been maintained in humid cages as they prefer, but with little ventilation provided to prevent fungus growth.
  • Bacteria - Bacterial infections of the skin may resemble the fungal infections described above and recommendations for prevention are the same. Other common bacterial infections may inhabit the intestinal tract, reproductive system, respiratory system, or even the circulatory system. Most bacterial infections in reptiles are gram-negative and fairly easily treated with antibiotics if accurately diagnosed and caught early. Careful attention to hygiene is required to prevent bacterial infections as they are quite common and are easily transmitted. Sanitation of water bowls is of primary importance, as is the cleanliness of feeder rodents and insects offered to our charges. Number one source of infection in captive Leopard Geckos has proven to be the contaminated water bowls used in cricket cages!
  • Virus - Little is known about most viral infections in captive reptiles, but they do exist. There are no treatments for viral infections and strict quarantine of newly acquired specimens is of paramount importance prior to introduction to captive colonies. Sadly, immediate euthanasia may be an important tool in preventing spread of these extremely contagious organisms.

Endo-Parasitic Diseases

Endo-parasitic diseases are caused by many types of organisms which enter the host through various mechanisms and reproduce. Microscopic organisms include protozoa and amoeba. Larger organisms includes numerous types of 'worms'. The vast majority inhabit the digestive tract and accurate diagnosis is possible through presenting a stool sample to your veterinarian for microscopic analysis. ALL require a veterinary diagnosis and prescribed medications for successful treatment. SOME can be transmitted to humans, a FEW may prove infective to humans, causing disease. While there are far too many types to include them all here, we'll present some of the most common ones. Commonly encountered forms fall into several groups:

  • Protozoa & Amoeba - This is the reptilian version of the "Mexican Two-Step' and is usually caused by the same source, a lack of clean drinking water. Many methods of infection are possible, all involving direct contact with contaminated feces, water, food items, or another infected reptile. Again, prevention is the best cure as they are easily transmitted from host to host. Careful attention to hygiene practices is required to prevent spread. This is especially important with regard to water bowls. Many reptiles spend time soaking in their dishes, contaminating the water source or even fouling it directly with fecal matter. Make sure you use a type of dish that can be sterilized, and do so often. I mean you don't drink your dirty bath water, so why allow your pet reptile to do so? Initial symptoms include listlessness, regurgitation, and diarrhea, and the stools often are grayish colored and have a sickly sweet smell. Stools in advanced cases may also contain blood. The majority of cases can be treated successfully with oral Flagyl (Metronidazole), but it is still recommended the keeper seek veterinary diagnosis both to confirm the organism present and to prescribe the needed medication.
  • Coccidia - Coccidial infections are surprisingly common in captive reptiles, and can be difficult to diagnose. Many reptiles are capable of long-term survival with very very mild cases, which may suddenly bloom to severe proportions when conditions causing stress are provided. Very common and easily transmitted in Leopard Geckos, Bearded Dragons and many other common species. An extremely severe form, known as Cryptosporidia is proving nearly untreatable and is very difficult to diagnose.
  • Roundworms (Ascarids) - One of two types of worm easily visible to the naked eye, adult Roundworms usually range from 1/2 to just over an inch in length. Most are white in color and resemble sections of spaghetti noodles. Veterinary diagnosis to confirm ID and treatment with prescription drugs is required, but usually not difficult, and unless severely infested, your reptile will stand a good chance of full recovery.
  • Hookworms - Invisible to the naked eye, Hookworms can quickly overwhelm a host reptile. Symptoms include bloody mucous filled stools. Strict cleanliness procedures can aid in preventing the endless cycle of re-infestation common in filthy reptile enclosures. Veterinary diagnosis to confirm ID and treatment with prescription drugs is required.
  • Pinworms - Invisible to the naked eye, Pinworms are surprisingly common, but usually not cause for much concern as only very severe cases will present themselves diagnostically. Pinworms are often ingested from host organisms, including feeder rodents and insects. Such species are usually incapable of infecting reptiles and are simply passed through the digestive tract. Veterinary diagnosis to confirm ID and treatment with prescription drugs is required.
  • Tapeworms - Easily visible to the naked eye, tapeworms (or more commonly single segments of them) are often found in the stools of infected reptiles. Veterinary diagnosis to confirm ID and treatment with prescription drugs is required.

Ecto-Parasitic Diseases

These are what most people think of when they hear the word parasites. The most common types in captive collections are mites and ticks, both of which adhere to the skin surface where they puncture the skin and consume blood.

  • Mites - Jokingly referred to as the 'pet shop plague' the best cure for these little nasties is prevention. Mites are readily visible to the eye as tiny specks which can be seen moving about on the skin, particularly in folds or creases. In truth, purchasing reptiles from a high-quality breeder will virtually assure mite-free stocks whereas acquiring reptiles from pet stores will almost guarantee a free case of mites at some point. They are simply a common by-product of the imported reptiles which these store frequently traffic in. Quarantine of newly acquired specimens is recommended and many over-the-counter remedies are available, most of which will be available at your local pet shop.
  • Ticks - Essentially a much larger version of mites, these are found primarily on recently imported reptiles, especially those of African origin such as Ball Pythons. Cure is simple, and you can probably avoid the vet bill on this one. Just get out your magnifying glass and tweezers and pluck them off, swabbing the immediate area with rubbing alcohol each time. It pays to change bedding at this time as well to remove any ticks which have dropped off the reptile to lay eggs. Repeat this weekly until you are certain you've gotten them all. Usually, a month or so of this is all it takes. However, watch for infections at the locations where the ticks were plucked. Occasionally, these little punctures they create may become infected, especially in the cloaca tissues.

Environmental 'Diseases'

Not really a disease, but many environmental problems cause various maladies which keepers will recognize as a 'sick' animal. So a few are covered here.

  • Humidity - Problems with humidity tale two forms, too high and too low. Excessive humidity can provide ideal conditions for fungal and bacterial infections to develop. Conditions which are too dry often lead to problems with ecdysis (shedding). Lizards will often retain bits of skin shedding on the toes and tail tips. If not removed promptly, these can cause blood flow restrictions and eventual tissue death, perhaps resulting in amputation of the affected areas. Snakes may retain skin on the tail tip as well, and will often fail to remove the spectacle or eye caps. In severe cases, the entire skin shedding may fail to separate and will adhere tightly to the skin surface! Always check your reptile after shedding for these problems and take immediate actions to correct any humidity problems within your cages. Prompt removal of the offending skin is usually easy, and can be made easier still by soaking the affected areas in water for several hours prior to removal.
  • Temperature - Problems with temperature also fall neatly into two forms, too high and too low. Excessive temperatures can result in dehydration, or even paralysis and eventual death. Temperatures which are too low can be much more subtle. While most reptiles can easily handle exposure to cool temperatures for a short period, a long-term exposure to sub-optimal temperatures almost always results in problems involving with either the respiratory or digestive systems. Always check temperatures throughout your cage (we recommend using non-contact infrared thermometers for this), never assume that since just one area is acceptable, all is well. Many reptiles will seek out a hiding area and stay in it regardless of temperature as security may be of more importance to them than temperature! Many keepers each year are surprised to discover just how cool it can get in such places, and just how sick their charges have become while hiding in them. There is no excuse for burning the cake because you failed to check temperatures, and no excuse for letting your reptile get sick for the same reason.
  • Burns - 99% of all burns happen for one of two reasons, and both are very simple to prevent. Physical contact with excessively hot surfaces (usually light bulbs) should be avoided by providing a physical barrier between the bulb and your reptile. If you think it's a bad idea for you to lick a hot light bulb, then it's a bad idea to allow your pet reptile to do so. Pretty self-explanatory...  A somewhat more subtle, but often serious, form of burn occurs when the basking or warming spot provided is too small for the animal in question. What happens is the animal attempts to bring it's full body temperature up to a certain point by staying on the hot spot, even while burning. It's sort of like standing in Antarctica and trying to keep warm by holding your hand over a candle. Prevention is fairly simple, just make sure the basking lamp or heating pad used is of adequate size to allow the entire animal to warm at one time. Double checking the remainder of the cage to insure it is not excessively cold will also help.
  • Wounds and Abrasions - Wounds are usually caused by two problems, and both are easily avoided. The first is physical contact with sharp objects placed in the cage for decoration (just don't do it) and the second is attacks by food animals. Many keepers are surprised to discover that uneaten prey items can turn the tables on their pets. Mice, rats, and even crickets can all put some serious hurt on a reptile if left in the cage unattended. It's best to remove uneaten food items after an hour or so to avoid this. Abrasions are also relatively common and most are easily avoided. Most common are abrasions to the rostral area caused by rubbing the nose on a rough surface (usually a screened cage opening) in attempts to escape. Less common are abrasions to the plastron of turtles and tortoises from rough substrates or decorations within the cage. Try to avoid using very rough screens and decorations in your cages to prevent abrasions, and be certain to provide adequate hiding areas within your cages. Many reptiles are really just searching for a place to hide, rather than trying to escape.

General Hygiene

To me, this subject seems like common sense. Promptly removing feces, sterilizing contaminated surfaces and caging with Roccal, Nolvasan, or simple Bleach Water mixtures is fundamental. A mixture of 1/3 cup bleach to a gallon of water is suitable for use in general cage cleaning. Keeping a spray bottle of the solution handy for "spot-cleaning" fresh messes is a good idea.

Preventing contaminated water through frequent changes and sterilization of water dishes is another frequently ignored, yet critical component of successful reptile care. Soaking water dishes for a few hours in the same bleach water mixture will sterilize them well, but avoid using dishes made of absorbent materials. Many "naturalistic" looking water bowls sold today are actually quite difficult to sterilize, and such types should be avoided. Simple glass or plastic dishes are best and many large-scale keepers (ourselves included) simply use disposable plastic dishes.

Wash your hands! I know your mother told you to do this, and she was right. Washing hands using ordinary anti-bacterial hand soap will go a long long way towards preventing spread of disease between specimens, not to mention prevent giving it to yourself.

Speaking of spreading diseases between specimens, avoid playing "musical mousy". If your snake didn't eat it, there might be a reason - don't pass that reason on to another snake. Discard the mouse.

Practicing simple quarantine procedure may also prevent the loss of a cherished pet. Don't go out and buy a male Bearded Dragon and take it home and dump it in with your two females. Such quickie breeding projects can have disastrous results, with all three suddenly developing problems. Quarantine new acquisitions for at least 30 days before introducing them, preferably for 90 days in a separate room.


If there's a conclusion to be drawn here, it is simply that it is your responsibility to provide your captive reptiles with proper environmental conditions. To provide them with clean sanitary drinking water and caging. To take them to a qualified professional for diagnosis and treatment if something should appear out of sorts.

Sounds easy, so why do so few do it? Simply put, it's because reptiles are silent about their problems. They don't cry out, they don't get diarrhea all over the carpet, throw up in your slippers, or any of the things that will cause us to rush the dog to the vet. They just make a mess in their cages, where it's out of sight and then will lie there quietly dying without complaint - and are all too easily ignored as a result.

Please be responsible and care for your pet properly, taking interest in it's welfare and consulting a professional if you feel there are problems! If you can't or won't do this, give the animal to someone that will and then don't acquire another. Keeping pets of any type should be viewed as a privilege, not a right. If it sounds like I'm soap-boxing here, tough. These are a lot kinder words than those you'll hear from me after you've violated that privilege.