Reptile · Iguana iguana · typical adult weight 1.00–5.00 kg
Butorphanol is dosed at 8 mg/kg IM not stated in the cited source in green iguanas, per Greenacre CB, Schumacher JP, Talke G, et al. Comparative antinociception of morphine, butorphanol, and buprenorphine versus saline in the green iguana, Iguana iguana, using electrostimulation. J Herp Med Surg. 2006;16:88-92. doi:10.5818/1529-9651.16.3.88 — Verified against Mader's Reptile and Amphibian Medicine and Surgery, 3rd Ed, p.570 (2026-08-01). — SOURCE EDITION: Mader's Reptile and Amphibian Medicine and Surgery (Divers & Stahl) — ISBN 9780323482530, https://openlibrary.org/isbn/9780323482530. Butorphanol is used in green iguanas for Analgesia (antinociception) - electro-stimulation model; PROVIDED analgesia; adverse effect: delayed righting reflex, Analgesia (antinociception) - electro-stimulation model; PROVIDED analgesia. Routes documented in green iguanas: IM. A typical adult green iguana weighs 1.00–5.00 kg. ExoticRx lists 2 cited dose rules for Butorphanol in green iguanas, drawn from published veterinary references. Verify against current literature before clinical use.
US trade names: Torbugesic, Torbutrol
| Route | Dose | Frequency | Indication | Evidence | Source |
|---|---|---|---|---|---|
| IM | 8 mg/kg | not stated in the cited source |
| Analgesia (antinociception) - electro-stimulation model; PROVIDED analgesia; adverse effect: delayed righting reflex |
| Weak |
| Greenacre CB, Schumacher JP, Talke G, et al. Comparative antinociception of morphine, butorphanol, and buprenorphine versus saline in the green iguana, Iguana iguana, using electrostimulation. J Herp Med Surg. 2006;16:88-92. doi:10.5818/1529-9651.16.3.88 — Verified against Mader's Reptile and Amphibian Medicine and Surgery, 3rd Ed, p.570 (2026-08-01). — SOURCE EDITION: Mader's Reptile and Amphibian Medicine and Surgery (Divers & Stahl) — ISBN 9780323482530, https://openlibrary.org/isbn/9780323482530 |
| IM | 1.5 mg/kg | not stated in the cited source | Analgesia (antinociception) - electro-stimulation model; PROVIDED analgesia | Weak | Carpenter JW, Klaphake E, Gibbons PM, et al. Reptile formulary. In: Divers SJ, Stahl SJ, eds. Mader's Reptile and Amphibian Medicine and Surgery, 3rd ed., Elsevier, St. Louis, MO; 2019:1191-1211. / (green-iguana-specific row, p.252) 131. Fleming GJ, Robertson SA. Assessments of thermal antinociceptive effects of butorphanol and human observer effect on quantitative evaluation of analgesia in green iguanas (Iguana iguana). Am J Vet Res. 2012;73:1507-1511. — Verified against Carpenter's Exotic Animal Formulary, 6th Ed, p.236 (2026-08-01). — Carpenter's Exotic Animal Formulary 6th ed, Table 4.5 (Chemical Restraint/Anesthetic Agents Used in Reptiles.a). Located 2026-08-05: the only table covering this species in which the drug's own row prints this dose. The copy held is an ebook conversion with no printed page numbers, so the table is the citable location. — SOURCE EDITION: Carpenter's Exotic Animal Formulary — ISBN 9780323833929, https://openlibrary.org/isbn/9780323833929; Mader's Reptile and Amphibian Medicine and Surgery (Divers & Stahl) — ISBN 9780323482530, https://openlibrary.org/isbn/9780323482530 |
Every held source for this drug and species, as printed. Where they differ, both are shown — the choice is yours, not ours.
The sources disagree for this combination. The ranges below do not overlap on a comparable route. This is not an error in one of them — published veterinary references differ, and reconciling them for a particular patient is a clinical judgement.
| Dose (mg/kg) | Route | Source | As printed |
|---|---|---|---|
| 0.5–2 | IM | BSAVA Small Animal Formulary, 10th ed — Part B (Exotic Pets)p.61 | Doses of 0.5-2 mg/kg i.m. q24h have been suggested for sedation but are not proven to provide analgesia. Beard |
| 1.5 | IM | BSAVA Small Animal Formulary, 10th ed — Part B (Exotic Pets)p.61 | roven to provide analgesia. Bearded dragons, Green iguanas: 1.5 mg/kg i.m. q24h c |
| 0.2–0.5 | IV | Carpenter's Exotic Animal Formulary, 6th edTable 4.5 | 0.5-2 mg/kg IM or 0.2- 0.5 mg/kg IV, IO |
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These ranges are per kg. Enter your green iguana's weight to get the precise dose and draw-up volume — unit and concentration math done for you.
Kappa-opioid receptor agonist and mu-opioid receptor antagonist. Provides visceral analgesia and sedation.
Short duration of action (1-2 hours). Better for visceral than somatic pain. Ceiling effect on analgesia. May cause sedation and mild respiratory depression.
Species-specific contraindications and adverse-reaction reports for green iguanas may differ from canine / feline reference data — consult the primary citations listed with each rule.
Butorphanol dose ranges in green iguanas, with cited source references: IM 8 mg/kg not stated in the cited source; IM 1.5 mg/kg not stated in the cited source. Reference ranges from cited sources — verify against current literature before clinical use.
Documented routes for Butorphanol in green iguanas: IM.
Butorphanol is indicated in green iguanas for: Analgesia (antinociception) - electro-stimulation model; PROVIDED analgesia; adverse effect: delayed righting reflex, Analgesia (antinociception) - electro-stimulation model; PROVIDED analgesia.
These are general warnings for Butorphanol across species; consult the green iguana dosing table above for species-specific guidance. Short duration of action (1-2 hours). Better for visceral than somatic pain. Ceiling effect on analgesia. May cause sedation and mild respiratory depression.
Why a species-specific page? Butorphanol pharmacokinetics differ across species: dose ranges, intervals, and route preferences are not interchangeable. Cross-extrapolation from canine doses is unsafe in green iguanas — the rules above are the citations specific to this species, not generic recommendations.
Sourced from published veterinary references; awaiting credentialed clinical reviewer. See our editorial process. Reference only — not veterinary advice.
| 1–1.5 |
| SC |
| Carpenter's Exotic Animal Formulary, 6th edTable 4.5 |
| 1-1.5 mg/kg SC, IM |
| 0.4–1 | SC | Carpenter's Exotic Animal Formulary, 6th edTable 4.5 | 0.4-1 mg/kg SC, IM |
| 0.5–2 | IM | Carpenter's Exotic Animal Formulary, 6th edTable 4.5 | 0.5-2 mg/kg IM or 0.2- 0.5 mg/kg IV, IO |
| 1 | IM | Carpenter's Exotic Animal Formulary, 6th edTable 4.6 | 1 mg/kg IM |
| 2 | — | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 127.5 | (B) 0.4 mg/kg + (Mi) 2 mg/kg IM22 Most species/preanesthetic; administer 20 min before induction |
| 0.4–1 | IM | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 127.6 | 0.4-1 mg/kg SC, IM295 Most species; sedation; preanesthetic; 0.2 mg/kg IM used experimentally in tortoises98 |
| 1 | — | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 127.6 | 1 mg/kg IM84 Green iguanas/ineffective for analgesia; presence of observer may affect iguana response |
| 0.2–0.4 | — | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 128.4 | 0.2-0.4 mg/kg IM52 Analgesia; efficacy uncertain52 |
| 0.4–1 | SC | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 127.4 | 0.4-1 mg/kg SC, IM295 0.5-2 mg/kg IM, or 0.2-0.5 mg/kg IV, IO2 Most species/sedation; preanesthetic 3 Most species/preanesthetic |
| 0.5–2 | SC | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 127.4 | 0.4-1 mg/kg SC, IM295 0.5-2 mg/kg IM, or 0.2-0.5 mg/kg IV, IO2 Most species/sedation; preanesthetic 3 Most species/preanesthetic |
| 0.2–0.5 | SC | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 127.4 | 0.4-1 mg/kg SC, IM295 0.5-2 mg/kg IM, or 0.2-0.5 mg/kg IV, IO2 Most species/sedation; preanesthetic 3 Most species/preanesthetic |
| 1–1.5 | SC | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 127.4 | 1-1.5 mg/kg SC, IM295 Lizards/administer 30 min before isoflurane for smoother, shorter induction |
| 0.4 | — | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 127.5 | (B) 0.4 mg/kg + (Mi) 2 mg/kg IM22 Most species/preanesthetic; administer 20 min before induction |
| 0.08 | — | Mader's Reptile and Amphibian Medicine and Surgery, 3rd edTable 127.5 | (B) 0.4 mg/kg + (Me) 0.08 mg/kg IM95 Green tree monitors/sedation |
Figures are transcribed from the cited page or table of each held edition and are shown for reference only. They are not dose recommendations, they do not feed the calculator, and none has been reviewed by a veterinarian.