Baytril/Enrofloxacin...and the bacteria that fear it

By Bill Strand


Strand, B. (2003). Baytril/Enrofloxacin...and the bacteria that fear it. Chameleons! Online E-Zine, January 2003. (

The Problem

Bacteria surrounds us. It is found on the things we touch and in the air we breathe. Bacteria is constantly looking for places that are hospitable to feed and breed. Our immune system is an impressive, complex system and spends much of its time repelling bacteria before it has a chance to get a foothold. And once a bacterial colony does take hold and begin an infection the immune system works on clearing the problem up. This same constant struggle is waged by chameleons and their immune systems. When conditions are perfect and the animal is healthy the chameleon's immune system does a wonderful job of fighting off the bacterial invaders. Unfortunately, when things do not go right the bacteria sometimes get the upper hand. Things not going right may include physical trauma (such as breaks in the skin due to cuts) and anything that compromises the immune system (such as adverse environmental conditions and stress). This is when the bacterial invaders meet a weakened immune system and are able to set up camp. First let's take a look at what bacteria are.

The Enemy

Bacteria are single celled organisms that inhabit most every place on Earth. Some species of bacteria are beneficial to animals, some are dangerous (pathogenic). They are so small that it would take 1000x magnification to view them. Like every living organism, their purpose is to reproduce. This is exactly what they do when they find their way into a body and are not successfully repelled by the immune system. Their very presence produces inflammation and their waste products can be toxic.

The Solution

The solution to a bacterial infection is to get the immune system back to working order. Unless the bacterial infection occurred due to a wound, the fact that a bacterial infection occurred is an indication that the immune system has weakened. This is significant for us as chameleon keepers and the reason why there is so much more in this article than a description of the anti-bacterial agent Baytril. Antibiotics are tools that give the body's immune system a hand in fighting off the bacteria. But, in many cases, the bacterial infection is merely a symptom of the real problem. A weakened immune system can be due to many things directly in our control. Our care of our chameleons has direct effects on the chameleon's immune system. If a chameleon is treated with an antibiotic, but the immune system is not restored then you are doomed to relive your problems. After the description of Baytril this article will touch on some aspects to look at in husbandry to treat a depressed immune system.

The Soldier

It must be noted that the information on the character and methods of Baytril come from the information label written by Bayer and they have tested this drug only on cats and dogs. It appears to be effective in chameleons and so it is assumed that some of the same mechanisms are at play.

Possibly the most common antibiotic used by reptile veterinarians for chameleons is Baytril. Baytril (also known as Enrofloxacin) is made by Bayer and is available as tablets or as liquid. Liquid is used for chameleons and may be injected or taken orally. Baytril is bactericidal which means that it kills bacteria. In the case of Baytril, this bactericide stops cell respiration and reproduction.

Baytril has become very popular as it is "broad-spectrum" (meaning it is effective against a wide range of dangerous bacteria) and it does not show side-effects when given within standard dosages. Of course, more experimentation is constantly being performed by the veterinary community as Baytril is has not been tested for use in reptiles and what is considered a "standard" dose will vary from vet to vet depending on their personal experiences. The veterinary consultant for this article, Dr. Tom Greek, knows of no case of overdose. That is not to say there is no effect of an overdose, but it indicates that overdose levels may be much higher than we currently experiment with. There has been speculation in the chameleon community that beneficial bacteria are damaged as well as the pathogenic, but no solid evidence supports any need to re-introduce any bacteria after a Baytril treatment.

Each case must be taken into account individually, but, generally, chameleons are given Baytril orally. The reason behind this is that even though injection will get the antibiotic in the blood stream quicker, injection also produces stress and pain that may be more harmful than the bacteria. Anyone who has had to give a chameleon an injection has witnessed the stress involved on the chameleon's part. A Baytril regimen (depending on your vet's prescription) may have a dose given two times a day for up to two weeks. This would be traumatic for a chameleon.

When given orally, Baytril is rapidly absorbed by the digestive tract. It then finds its way into the blood stream and ends up in tissues throughout the body.

The Analysis

To do a true test to see if an antibiotic should be used a culture and sensitivity test must be done. To do this the vet will take an appropriate sample from the chameleon depending on what the problem is and where (i.e. a throat swab,...). From this sample the vet will culture the bacteria and test to see what antibiotics are useful against the particular bacteria seen in the sample. The vet will want to use as narrow spectrum of an antibiotic as possible as this will target the specific bacteria and, hopefully, leave the other non-pathogenic bacteria unharmed. Unfortunately, a culture and sensitivity test will only tell you if certain bacteria are present. It will not tell you if those bacteria are what is causing the animal to be sick.

Many people do not want to spend the money to do a culture and sensitivity test and that is where Baytril does well. In the case where the vet feels that an antibiotic is needed and the client does not want to spend the money to be sure of the right drug to use Baytril is a good guess. It is effective against many of the possible bacteria that cause trouble and it does not exhibit side effects. This should not be taken as an endorsement of the guess method as it is possible that Baytril will not cover the bacteria in question. Only a culture and sensitivity would confirm this.

Given in proper dosage, there are no known DIRECT side effects of Baytril itself, but there is an important indirect effect of treatment when you are not sure 1) If Baytril will attack the bacteria in question or 2) If it is a bacterial problem in the first place. The danger, of course, is that you are not treating the real problem and the real problem continues to grow while you have stop looking for it. Do not be satisfied that you have left the vet office with some sort of drug to give to your chameleon. Do everything in your power to make sure it is the right drug!

The Battle

Once a prescription is given two actions are very important:

1) Perform the treatment according to the time scale given to you by your vet. If the vet says to do it two times a day for 10 days then make sure you follow through for the entire dosage. If you do not then all the cost and effort of the vet visit is wasted and, quite possibly, you are in for another round of problems. The first treatment will not kill all the bacteria. It takes time to root out the entire infection and this is done by maintaining a certain level of antibiotic coursing through the animal. This takes time. If you stop half way through the animal may have shown improvement, but you have left a small colony which can re-populate. Even worse, you have left a small colony of bacteria that may now build up a resistance to your antibiotic. When the infection comes back in full force your antibiotic may not be as effective the second time around.

2) Watch your chameleon's progress closely. Veterinary medicine is a challenge and each diagnosis is a detective case. The vet will gather the clues and make a guess as to what is going on. This can be very tricky when dealing with internal infections that can not be directly tested because the technology is not there, the animal is too sick, or the owner doesn't want to pay for the test. The more the vet's hands are tied for any of those reasons, the more of an educated guess the vet has to make. It is important that you provide the feedback necessary for the vet to know if the treatment is working. Observe your animal as the treatment progresses. Although the chameleon may not get better quickly, at least make sure the chameleon is not getting worse. Ask the vet when they would like to hear back from you as to the progress of the animal and make sure you give a call at that time. If the animal continues to go downhill even after treatment has started then you must consider that the animal is too far gone or else that there is something else wrong and the Baytril (or whatever medication is being used) is not attacking the true problem. Your veterinarian is a tool. You are paying for their experience. But you are still a major part of your animal's recovery. View your vet more of a team member than a god which will create a potion to fix all your animal's woes. Your adherence to the prescription and dutiful observation of the recovery (or lack thereof) is your part of the teamwork.

The War

Knocking down a bacterial infection is only part of the problem. To provide a full recovery you must determine the cause of the infection. An infection that results from a suppressed immune system usually requires a detailed look at husbandry. The chameleon has been weakened somehow and it is your job to fix the conditions that led up to that weakening. Things that could contribute to a weakening of the immune system are on the following check list. Go through it and see if any of these points need addressing.

  1. Temperature: Do you have a basking spot? Can the chameleon warm up or cool down at its leisure? Maintaining a correct body temperature is the chameleon's responsibility, but it is your responsibility to provide the proper gradient for that particular species (see the November 2002 issue for more on gradients).

  2. Humidity: This is a tricky one which requires research for the particular species you have. Too much can be as bad as too little.

  3. Light: Light is important for physical as well as mental health.

  4. Security: Does your chameleon have a place to hide? A chameleon that does not feel secure will be stressed. Each chameleon has their own comfort level.

  5. Cage Mates: One chameleon per cage. Nobody who is in love with the idea of a "pair" of chameleons wants to hear this and they will subsequently ignore this advice with the insistence that their case is different. For those who are not yet convinced their chameleons are social animals, don't even start this way! This induces low-levels of stress and that weakens the immune system. It may not show up today. Maybe not next month. But sooner or later it will happen. If you really must play around with this wait until you are experienced enough to know the subtle signs of trouble.

  6. Handling: Every chameleon will deal with being handled differently. Keeping your chameleon as a look-at-me pet instead of a hold-me pet will take this potential stress inducer out of the mix.

  7. Water Sanitation: How clean is the water the chameleon drinks? Is it recycled through the cage? Water should be from a clean source and never recycled through the cage. Chameleons are notorious for defecating in their water. You don't need that going through the cage or being spit out your pretty waterfall.

  8. Food Sanitation: Do your crickets walk on the bottom of the cage - or anywhere else your chameleon has defecated or other crickets have died? If so, you are feeding your chameleon a good portion of bacteria. Poop and dead bodies must never be near food. This takes everyday vigilance on your part.


As with any drug, Baytril is only a tool. It must be used properly in conjunction with proper support from you and your vet. Baytril has become a very popular drug because of its effectiveness and lack of side effects. I have even heard of reptiles being jokingly diagnosed as having a "Baytril deficiency"! We in the chameleon world are lucky to have such a tool at our disposal. It is our responsibility to understand it and use it properly!


Encyclopedia Britannica, 1992 Macropaedia Volume 4 pp570 -586

Dr. Tom Greek, Eastlake Animal Hospital, personal communication

Baytril (Enrofloxacin) information insert

Bill Strand

Bill Strand currently works in the area of exotic animal breeding and continues to refine husbandry techniques with a broad range of chameleon species. A special interest of his is the creation of captive environments. He was the Assistant Editor and Webmaster of this Chameleons! E-Zine from March 2002-March 2004.


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