Ways of treating reptiles Reptile breeder and veterinary surgeon Tariq Abou-Zahr follows up his article last month on what can be done for a sick reptile, switching away from methods of diagnosis of the cause of the illness to the growing range of possible treatment options that are now available today. Introduction I previously considered how you might go about choosing a vet to care for your reptile(s) and what might happen when an animal is presented to an exotic vet. Various different diagnostic possibilities were considered, as well as key methods such as the standard history taking and clinical examination that help to provide pointers to the cause of the problem. Assuming the cause of the problem has therefore been determined, so we now need to consider some of the options for potential treatment. To summarise all possible treatments for every documented conditions in a few pages in a magazine is clearly impossible, but some generic methods of treatment are worth discussing. Bear in mind that everything in reptiles happens quite slowly in comparison with mammals and birds, and therefore a course of treatment (such as a course of antibiotics) for a reptile is likely to be considerably longer than for a cat or a dog. This may in turn mean that the cost of treating a condition is higher, as more visits to the veterinary surgery are likely to be required, and more medication is likely to be needed. Medical management Many conditions can be managed medically, without the need for surgery or more involved treatment. A wide variety of potential drugs are available for treating reptiles. One important point to mention, however, is that while an array of drugs can be used and a large amount of information is available regarding safe and effective dose rates, very few products are officially licensed for use in reptiles. The reason for this is that in comparison with dogs and cats, not to mention food producing animals and ourselves, reptiles represent a relatively small market for the pharmaceutical 10 Practical Reptile Keeping
Therapeutic drugs have not been tested extensively on reptiles even in common species such as leopard geckos. FEATURE Veterinary viewpoint than stopping halfway through it it appears to have recovered. This greatly increases the risk of drug resistance developing, and there is always the risk that your reptile s condition may deteriorate again. Equally, don t keep any antibiotic treatment that you have left over, in the hope that it might be useful in the future. For exactly the same reason, there is then unlikely to be sufficient to provide a full course, even if that particular antibiotic by chance is the right choice, and it is still in date. companies. It costs a lot of money to licence a drug for a particularly condition in a particular species, as a result of all the testing that is required, and therefore most drugs are used off-licence when treating reptiles. Veterinary surgeons are still permitted to use unlicenced medications, but they must follow a so-called prescribing cascade (the details of which are beyond the scope of this article). They must also obtain written consent from the client permitting them to use unlicenced drugs. Expect to be asked to sign an off-licence declaration, which may be separate to the consent form if your reptile is being admitted to the hospital, or it may be combined with the general consent form. Some of the most common categories of drugs used are listed below. Antibiotics While many people are aware of the purpose of antibiotics, there are a considerable number of the general public who have totally unrealistic expectations when it comes to antibiotics. Many owners seem to think they are the answer to everything. I often have owners that, in the face of a complex non-infectious condition, will ask: Can we just have some antibiotics instead? So what are the ground rules with antibiotics? Firstly, they work by killing bacteria. They do not kill viruses nor will they kill fungi. Rule 1 therefore is that they certainly will not fix a problem that does not involve bacteria, whatever it might be! Sometimes, they can be used alongside other treatments, notably when a particular condition may cause suppression of the immune system, with antibiotic treatment then serving to minimise the risk of secondary bacterial infections by opportunist microorganisms. Different antibiotics work better for different types of bacteria. This is one of the reasons why it pays dividends to go for a culture and sensitivity testing in the face of an infection. This will prevent the use of antibiotics that are never going to be effective for the particular microbe in question, because of resistance. In reptiles, many of the bacteria that we see are highly resistant to a number of commonly used antibiotics, and so it is especially important in these animals in particular that culture and sensitivity testing is carried out routinely. As mentioned in the last month s article however, there may be certain circumstances whereby culture and sensitivity testing is not worthwhile, but your vet will be able to advise you accordingly in these situations. Starting a course of antibiotics and then carrying out a culture and sensitivity test is also not recommended, because the treatment may have masked the true nature of the infection. Some of the most common antibiotic classes used in reptile medicine are the fluroquinolones, cephalosporins and aminoglycosides. Antibiotics are often not very effective when administered orally in reptiles and often the best way to administer them is by injection. Your veterinary surgeon will be able to show you how to do this safely. Some examples of specific antibiotics commonly used would include marbofloxacin, amikacin and cephtazidime these are generic names for the drugs, rather than brand names for them. When being given a course of antibiotics for your reptiles, bear in mind that certain drugs must be stored in specific ways; as an example, cephtazidime must be stored in the freezer to retain its efficacy. It is always vital to finish a course of antibiotics prescribed for your pet, rather Antibiotics are too often regarded as magic bullets, able to cure all conditions, whereas in reality, this is not the case. Different antibiotics work in different ways. Antifungals Fungal infections are relatively common in reptiles. This can be linked in some cases to their vivarium surroundings, particularly if the ventilation here is poor, the humidity high and the hygiene sub-optimal. Pathogenic (diseasecausing) fungi are typically present in most vivariums, but they are unlikely to cause a problem unless they are present in overwhelming numbers or, conversely, if the reptile s immune system in impaired in some way, with fungi generally being opportunistic pathogens. Antifungal drugs, in contrast to antibiotics, are usually administered orally rather than by injection. They can be quite expensive too, with drugs such as voriconazole costing around 45 a tablet. Antifungal medication can in some instances be nebulised into a MAY 2015 11
Ticks are much more of a problem in wild reptiles, compared with their domestic counterparts. They can cause irritate, infection, and spread various diseases. patient though, reaching directly into the respiratory tract and thus increasing their efficiency. Nebulisation is a process whereby a liquid containing the medication is turned into very small droplets. These are projected into the air as a mist or fog, which the reptile then breathes into its respiratory tract, taking in the drug here at the same time. Nystatin is commonly used as an anti fungal drug, and I have used this with good success, particularly in leopard geckos suffering with enteric yeast infections, which affect the digestive tract. Antivirals This group of therapeutic drugs has limited use in reptile medicine; perhaps the exception is in cases of respiratory infections in tortoises where herpes virus is often implicated. There are reports in the literature of an antiviral drug called acyclovir causing an improvement in such cases. Otherwise, there are few well publicised/mainstream uses for antiviral medications at present, although this could change, particularly as we develop a greater insight into the viruses that impact on the health of reptiles. Already, it is becoming clear that snakes can suffer from a range of such infections. Antiparasitic drugs Ectoparasites like mites that are external, and endoparasites such as various worms that are to be found within the digestive tract are extremely common in reptile practice. A variety of medications are prescribed routinely to help in treating parasitic problems. A nebuliser dispenses the drug through a very fine mist in the air, enabling it to be breathed in this method of treatment is very useful for combating respiratory ailments. Left and below: Herpes viruses, which are a particular issue in tortoises, can be overcome by targeted treatment with a drug called acyclovir. However, viral treatments are not widespread in the treatment of reptile ailments at present. Treatment of parasites should always be carried out after finding evidence of the parasite though, as opposed to being carried out simply as a matter of routine. In the case of suspected worm burdens, a faecal egg count should always be performed, so as to assess the extent of the worm burden and to try to establish what kind of worm is present. The appearance of the microscopic eggs in the sample will allow an experienced parasitologist to identity their source. Droppings do not necessarily have to be completely fresh to determine this and a sample from the last couple of days will be adequate. On the other hand, examination for motile protozoa that frequently cause problems in reptiles must be carried out on completely fresh faeces. Parasites in general may not kill a reptile, but they can have an adverse impact on its appetite over a period, resulting in a progressive loss of condition, and leaving it vulnerable to bacterial or fungal infections for example. In this respect, they can sometimes be described, with justification, as silent killers. Mites and ticks are a common problem, particularly in snakes and lizards. They are usually treated topically, where they are present, rather than by internal medication, although in the case of mites, treatment of the reptile s quarters is generally vital in preventing any recurrence. Even so, it is vital to 12 Practical Reptile Keeping
FEATURE Veterinary viewpoint follow the instructions for use carefully, and not just in terms of the frequency of treatment. Many of the drugs that would be used to control mites in other species must be used with care and not at all in certain reptiles. For example, the drug known as ivermectin is very toxic to chelonians and certain other reptile species as well, and so should never be used to treat any parasites in tortoises. Painkillers There are many thousands of different species of reptile of course, and the literature tells us that some painkillers drugs known as analgesics will work much better in some species than in others. A lot more research is still needed in this field to determine exactly which painkiller is most appropriate for which species, and under what circumstances. It is also important to bear in mind that analgesics can take a long time to work in reptiles. For chronic pain, non-steroidal anti-inflammatory (NSAI) drugs are often used, with an alternative being tramadol. For in-hospital use, opioid painkillers such as butorphanol, methadone and morphine are all commonly used. I typically use morphine before most surgical procedures and I start administering it in reptiles about 24 hours prior to surgery, so as to ensure it has sufficient time to take effect. Supportive care Many reptile patients are too sick to be discharged with medications. In such cases, a period of time spent in hospital may be necessary, enabling them to receive supportive care. Such support for reptiles focuses on two main areas (quite apart from the medications as needed), in terms of fluid therapy and supportive nutrition. Fluid therapy in reptiles can be challenging as intravenous catheters are often difficult to put in place, compared with other groups of pets, notably dogs and cats. Instead, intra-osseous Tortoises are vulnerable to picking up endoparasitic worms when they are feeding. Many reptile patients are too sick to be discharged with medications. In such cases, a period of time spent in hospital may be necessary Pain relief can be supplied in a number of different forms. catheters, which are placed into the bone, are often used in reptiles, where they can be held in place more easily. A small amount of local anaesthetic is used before placement of the catheter in these circumstances. Subcutaneous fluids under the skin are also frequently used in reptiles, often being helpful in the case of anorexic tortoises that have recently hibernated, but not regained their appetite, in spite of regular warm baths. A third option of intra-coelomic fluids is also a possibility, with the fluid being introduced into the rear part of the body, although this needs to be carried out carefully, and the positioning varies, depending on the animal concerned. In lizards as an example, a site in the area of the right side of the lower abdomen is usually recommended, so as to prevent any risk of hitting the bladder. Supportive nutrition is important, although particular care should be taken with patients that have not eaten for quite some time, because in these cases, so-called re-feeding syndrome can be a problem. Food can be gavage-fed, MAY 2015 13
using a specifically designed gavage tube directed into the reptile s stomach. In many lizards and tortoises that have not been feeding themselves for a prolonged period, it may be necessary to insert a so-called pharyngostomy feeding tube. A very small hole is made in the side of the neck in a sedated animal, with local anaesthetic having been administered here as well. The tube is secured at one end to the top of the reptile s head or on its shell. The other end is positioned in the stomach. In tortoises, these tubes can be left in place for many months as required, with the reptile still being able to feed directly alongside nutrition administered via the tube. When the owner is confident that the animal is feeding sufficiently on its own, and weight gain is evident, so the tube can easily be removed. Endoscopy I mentioned endoscopy in the last article as a means for potentially helping to reach a diagnosis. Endoscopy can also be used for treatment and a range of forceps/suction options and fluid pumping can be used in a channel alongside the endoscope. This allows for removal of foreign material or for the collection of samples for biopsy. Endoscopy in reptiles is a relatively specialist procedure and not all A recuperating tortoise with a feeding tube in place. Direct feeding in some species, such as box turtles, is often harder than in others. An endoscope is a flexible viewing tube, that can be used to obtain samples and for treatment too, with much less risk of causing haemorrhage, compared with conventional surgery. veterinary practices will be familiar with the techniques involved, nor will they have the necessary equipment. As reptile medicine becomes increasingly advanced and more widespread however, so the availability of endoscopy for such patients will doubtless continue to expand. Surgery It is my feeling that surgery in reptiles should only be attempted by veterinary surgeons who have some familiarity with and understanding of reptile medicine, as many of the principles associated with performing surgery in reptiles are very different compared with carrying out similar tasks in cats and dogs. There are certain conditions where surgery is always indicated though, as for example in female reptiles suffering from dystocia (egg binding) that have failed to respond to medical/ environmental management. Similarly, female reptiles suffering from follicular stasis, a very common problem especially in chameleons and tortoises will almost invariably require surgery if they are to survive. Foreign bodies and in particular, substrate impactions are often removed surgically. Orthopaedic surgery in reptiles is becoming much more frequently reported, as people discover novel techniques to fix fractures with very small implants. Some of the special considerations with regards to reptile surgery are as follows:- Anaesthesia Typically, injectable drugs are used for induction of anaesthesia, for the purpose of anaesthetising the patient initially, after which the reptile will be maintained on anaesthetic gas via a tube which is placed down its trachea. In some instances (particularly in very small patients such as geckos), gaseous induction might be used instead of injectable, such that the whole anaesthetic is performed with gas. Various volatile agents (gases) are used in reptile anaesthesia, but Isoflurane and sevoflurane are the most common. The most significant difference between reptile anaesthesia and cat or dog anaesthesia is that reptiles will always require ventilation under anaesthesia as they stop breathing for themselves. This ideally is performed using a specific mechanical ventilator, although if necessary it can be performed by hand. Through the course of an operation, reptiles receive oxygen alongside the anaesthetic gas. During recovery however, room air is needed instead of oxygen. While in mammals, the stimulus to breathe is an increasing level of carbon dioxide, the equivalent stimulus is actually a falling 14 Practical Reptile Keeping
A sick snake is unlikely to shed its skin normally, but tends to do so in pieces. A vet needs to take shedding into account, in terms of wound FEATURE healing Veterinary after surgery. viewpoint oxygen concentration in the case of reptiles. Therefore trying to bring a reptile round from anaesthesia on pure oxygen as you would with a cat or a dog is unlikely to lead to the animal rapidly returning to being able to breathe for itself. On the subject of recovery, it pays dividends to pay special attention to picking the right combination of anaesthetic drugs. Unfortunately, use of some drugs in reptile patients will lead to a delayed recovery of many hours. Other drugs provide much shorter periods of anaesthesia. Failure to maintain a reptile patient at a sufficiently warm temperature will also show its recovery, whatever drug is used. Special attention should be paid to be keeping reptile patients warm during surgery. Surgical considerations So that aseptic technique can be adhered to, ensuring that the operating site is sterile to start off, (as well as the surgeon and equipment), it is necessary to scrub the area where the incision will be made thoroughly beforehand. It is important to use an alcohol-free iodine scrub solution, because alcohol will lead to a rapid cooling of the patient as it evaporates. With any small patient, and reptiles are no exception, blood loss is a big consideration when it comes to surgery. Many reptiles sadly do not have a lot of blood to lose and steps must be taken to minimise blood loss wherever possible. The use of radio surgery is invaluable. This involves using ionising radiation to cut and coagulate the blood, as opposed to using a The anaesthetic process in reptiles is fundamentally different to that of mammals. scalpel blade and ligatures. Blood vessels can be stopped bleeding much more quickly this way and blood loss is minimised as a result. Whereas in cat or dog surgery, ligatures are used and placed by hand, using suture material for this purpose, it is often the case in reptiles that specially designed metal haemoclips/ligaclips are applied to the blood vessels instead. This avoids unnecessary pulling on delicate structures in order to tie ligatures and works to minimise blood loss further. When it comes to closing the surgical wound, special consideration has to be paid to the fact that reptiles will shed their skin at some point post surgery, usually before the wound has fully healed. This means that sutures must be placed in a specific fashion to avoid problems with shedding around the surgical wound (referred to as dysecdysis). A so-called everting suture pattern, where the scales/skin sticks out from the body a little bit is what is typically used to prevent this problem. In most mammalian patients, sutures are removed after 10 days. Once again though, because reptiles do everything slowly, it is necessary for sutures to be left in for a much longer period of time in these animals. As a general guide, a period of weeks is needed, and I often advise six weeks as the standard period. Further information Tariq Abou-Zahr BVSc MRCVS is a veterinary surgeon with a special interest in exotic species, as well as being both a keen herpetoculturist and aviculturist. He currently practices at Great Western Exotics, Unit 10, Berkshire House, County Business Park, Shrivenham Road, Swindon, SN1 2NR. Tel: 01793 603 800, email: swindonreferralsexotics@ vets-now.com Further reading Macarthur S, Wilkinson R, Meyer J (2004). Medicine and Surgery of Tortoises and Turtles. United States: Wiley Blackwell. Mader D (2006). Reptile Medicine and Surgery. Missouri: Saunders Elsevier. Girling S, Raiti P (2004). BSAVA Manual of Reptiles. 2nd ed. Gloucester: British Small Animal Veterinary Association. MAY 2015 15