Iguanas are among the most popular pet reptiles. They love to bask in the sun or under an ultraviolet light, and they enjoy a diet of leafy greens and vegetables. Many people don’t realize that iguanas can grow to be quite large, exceeding 6 ft (1.8 m) in length. Iguanas should be properly socialized when they are young to ensure that they can be handled as adults. They require specialized housing and regular veterinary care and may not be a suitable pet for everyone.

Biological Facts

  • Green Iguana: Iguana iguana
  • Tree-dwelling lizard native to Mexico and South America
  • Life span: 9 to 12 years
  • Weight (adult): 5 lb to 20 lb (2.3 kg to 9 kg)
  • Sexual maturity: 3-4 years
  • Incubation: 73 to 93 days
  • Average clutch size: 20-40 (hatchability may approach 100%)


  • Heat seeking: in the wild, spend many hours basking in the sun
  • Solitary by nature, except during the breeding season
  • Highly territorial; should be housed alone
  • Can become accustomed to human touch, but excessive handling may cause stress


  • Fresh, dark leafy greens such as kale, escarole, endive, collard greens, mustard greens, turnip greens, and leaf lettuce (Do not feed iceberg lettuce, as it lacks calcium and other nutrients.)
  • Vegetables such as diced yellow squash, zucchini, and grated carrots
  • Commercial iguana pellets
  • Only low-protein foods, as too much protein may cause kidney damage
  • Phosphorus-free calcium supplement dusted over greens daily for juveniles (animals up to 2 years of age) and once or twice weekly for adults
  • Fresh water daily


  • Large habitat that mimics the natural environment as closely as possible
    • Maintain a temperature gradient ranging from 75ºF to 80ºF (23.9ºC-26.7ºC) in the coolest area and up to 95ºF to 100ºF (35ºC to 37.8ºC) in a basking area. Use infrared lamps and ceramic heat emitters rather than under-the-cage heat pads or hot rocks, which can cause severe burns.
    • Provide ultraviolet (UV) light in the UVB spectrum. Lack of UVB radiation can cause vitamin D deficiency, inhibit calcium absorption, and result in metabolic bone disease.
    • UVB bulbs come in two forms: fluorescent and mercury vapor. Prices for these lights range from $30 to $75. Replace fluorescent bulbs every 6 to 9 months as UVB bulbs lose UV output over time even though they continue to produce visible light. Mercury vapor UVB bulbs continue to produce UVB radiation and need to be replaced only when they stop producing light.
    • Place UVB lights within 12 to 18 inches of the iguana’s basking area. The bulb should not be blocked by glass or plastic, which will filter out beneficial rays.
  • Reptile carpet or newspaper as bedding (Avoid bark and wood chips, which may cause intestinal blockage if ingested.)
  • Plenty of vertical space for climbing, with branches and platforms for perching
  • Fresh water in a large pan for soaking and to stimulate defecation (Change the water daily and when soiled.)

Preventive Care

  • Routine physical examination every 6 to 12 months
    • Consult a veterinarian with experience treating reptiles if you have any questions or concerns about your iguana’s health.
  • Annual fecal examination for parasites
  • Blood tests as recommended by your veterinarian
  • Spaying and neutering recommended

Common Medical Disorders

  • Abscesses
  • Egg binding in females
  • Internal and external parasites
  • Kidney disease
  • Metabolic bone disease
  • Prolapsed hemipenis in males
  • Thermal burns