The most common problems we see in pet Iguanas are infections, osteodystrophy and other mal-nutritional related problems. Parasites also cause reptiles to deteriorate in condition and the body’s ability to fight infections. Of the 600 species of Iguanids the green iguana and the spiny-tailed iguana are most commonly kept as pets. Iguanas are native from the geographical area from Mexico to South America. The average iguana lives only a few years in captivity, usually dying form complications due to malnutrition. If properly cared for an iguana can live to be 15 years old, and weight up to 15 pounds. These large iguanas can have a length of up to 7 feet in size. Periodically their claws (toenails) need to be trimmed.
Iguanas should be housed alone. If provided a lot of room you can have multiple iguanas, yet normally the average person does not have a cage as big as a small house. Iguanas will fight each other. A single iguana should be housed in a 3’ x 5’ by 5’ high minimum enclosure space. Within this space provide climbing limbs, hiding boxes and a place to bask under a UVB light bulb. We prefer the light bulbs specifically made for reptiles, with a UVA and a UVB spectrum. Glass should not be between the light and the reptile; a wire screen is adequate. The room temperature should not be below 70-75 degrees at night, and preferably 80-90 during the day. Hot rocks usually do not work as well as a light bulb outside one end of the environment in keeping one area near 95 degrees. Humidity should be at 70-80% or greater, which can be achieved by providing a 12” water basin within their cage and/or daily misting. This water bowl should be changed daily. In a dry winter a humidifier may be indicated. A daily misting or water bath also can be utilized. The development of mold is to be avoided. Small iguanas can be housed in aquariums with wire lids on top, larger lizards can be place in wire cages with a solid floor and/or very fine wire screen which will not catch a toenail or leg. If you use bedding newspaper is adequate. One can also take carpet and place it face down in the habitat. We do not recommend litter which will mold or cause problems if eaten. We do not recommend litter, sand, wood chips or even the digestible calcium containing sand products. You can clean the habitat 2-4x a month with a 1/30 bleach solution, rinse with water, paper towel wipe down and allowed to air dry for a few hours while the iguana is in a portable carrier or box with air holes. During the breeding season males may become territorial. A sneezing iguana can be normal, as this is a way to get rid of salts in their body.
A variety of foods is essential to maintaining the health of an iguana. Alfalfa sprouts, green beans, bell peppers, bok choy, broccoli, cabbage, carrots (grated), cilantro, clover, collard greens, corn, dandelion greens, endive, escarole, mustard greens, kale, okra, parsley, peas, peppers (sweet), romaine lettuce, spinach, sweet potatoes, snow peas, sprouts, squash, turnip greens (no turnips), watercress, zucchini, dark leafy vegetables and other mixes can be provided. Lettuce should be provided, but feed romaine lettuce not iceberg. The iceberg lettuce can harm reptiles and birds. The dark green-leaf vegetables should be about 1/3 of their diet. Bananas are to be routinely avoided, and some fruits such as apples kiwi fruit, mango, melons, papaya, peaches, pears, plums, soaked raisins, raspberries, strawberries and other fruits can be fed. If you feed beets, celery, rhubarb, Swiss chard or especially a lot of spinach the oxalate compound in these vegetables can tie up calcium, causing other problems. Use these oxalate containing plants sparingly, but in small amounts they are adequate. Collard and mustard greens contain > 7:1 ratio of calcium to phosphorus, which will counter balance the above oxalate plants. A total ratio of 2:1 calcium to phosphorus is preferred. Understandably if the iguana will eat a complete food they will be healthier. A complete vitamin/mineral mixture can be sprinkled on a green vegetable mix or lettuce 2-3x a week. The iguana should be fed daily. Even if you feed a commercially available complete diet, we advise the vitamin/mineral supplements and 40% of the diet be fed as fresh mixed vegetables. The herbivorous commercial diet should be at most 5% protein on a dry basis. To ensure the iguana eats a mixture of food, we advise that you use a food processor and chop up a mixture of food 1-2x a week, refrigerating the unused portion. Insects, such as mealworms and crickets are not routinely advised to be fed, but can in small amounts. Periodically you can also feed separately a very, very small amount of canned adult or geriatric 14% protein dog food (not puppy food or cat food that is too high in protein). Limit the low protein dog food to less than 5% maximum of the diet. Diets containing animal protein are not recommended.
Fibrous osteodystrophy is a major problem in iguanas; the newer name for this problem is metabolic bone disease (MBD). This metabolic disease causes the bones to become flexible and break easily. There are many interrelationships between calcium, phosphorus, vitamin D and sunlight which can cause this fibrous osteodystrophy problem; also commonly called osteodystrophy or nutritional secondary hyperparathyroidism. A swollen leg or mandible is usually early signs of osteodystrophy. In the summer months take your iguana outside and provide unfiltered outdoor light when possible. Placing the aquarium near the window does not prevent osteodystrophy, and may cause overheating. The unfiltered UVB light has a wavelength of 290-320, and is blocked out by clear glass or plastic. It only takes a few hours a day, outside in a cage during the summer, to help prevent osteodystrophy. We still advise the full spectrum lights and the complete diets with vitamin D3, yet iguanas can develop osteodystrophy if not provided with direct sunlight a few months out of the year. These UVB light bulbs need to be on 10-12 hours a day, within 18” of the iguana, and the bulb changed yearly (i.e. in the fall). A full spectrum or grow-lite bulb is not a UVB light. Iguanas can live in temperatures of 105 degrees, provided there is ventilation. There are some other lights available for reptiles, as discussed in the comparison of light bulb handout.
Sexing of iguanas and other lizards should not be done with the snake probe. A blood test is available to determine the sex of Iguanas. Male lizards (and iguanas) are usually brighter in color than females. It takes a couple of years before maturity is reached in iguanas. Behind and below the ear membranes is an operculum; males have a large shield than females. The inside of the back legs are scent glands called femoral pores. These pores are larger in males. Males also usually have a larger, thicker tail. On the top of the head of an iguana is a parietal eye, a gland which we believe senses light.
This is only a general guide for iguanas and we highly recommend the individual species books available for the wide variety of reptiles. We have more information within our library that you may read at the clinic. If you notice the iguana head bobbing, this is a type of communication. If you do not plan to breed reptiles, we recommend you keep one per habitat to reduce aggression and fighting wounds. All reptiles can be carriers of Salmonella, and we have more information if requested. Always wash your hands after handling any reptile. Signs of sickness in reptiles can be trouble breathing, constipation or egg binding, diarrhea, ear infections, swollen eyes, lumps, mouth rot, shell/skin rot, a softening shell, swollen eyes, increased thirst and/or not eating for a week or longer. Humidity over 60% may cause skin infections and blisters to form. The nose of an iguana contains a rhinal salt gland, to excrete excess salts. The white nasal crystals, when seen, may indicate a need to examine the diet for excess salts or potassium. We advise that you bring in a stool exam of all animals, including reptiles, so that we may run a fecal test for internal parasites.
The Staff at the Nelson Road Veterinary Care