Morphine

1–5 mg/kg, IM, SC, every 24 hours

10 mg/kg, IM, SC

Chelonians (red-eared sliders)

Lizards (bearded dragons)

Not analgesic for snakes. Causes pronounced respiratory depression in turtles.

Hydromorphone

0.5 mg/kg, IM, SC

Chelonians: appears to cause less respiratory depression than morphine

Tramadol

5–10 mg/kg, PO, every 2–3 days

Chelonians (red-eared sliders); less respiratory depression than morphine

Meloxicam

0.1–0.4 mg/kg, IV, IM, SC, every 24–48 hours

Ketamine

10–25 mg/kg, combined with dexmedetomidine 0.05–0.1 mg/kg and hydromorphone 0.5 mg/kg, IM (or 50% dose, IV)

Deep sedation/anesthesia in many chelonians. Reversed using atipamezole (0.5 mg/kg, IM) and, if necessary, naloxone (0.1 mg/kg, IM)

Midazolam

1–2 mg/kg, IM

Premedication

Tiletamine/zolazepam

3–12 mg/kg, IM

Tortoises, lizards, snakes. Low dose useful to facilitate intubation. Higher doses associated with prolonged recoveries.

Propofol

3–10 mg/kg, IV, intraosseous

Low dose rate for larger reptiles. Subanesthetic doses produce variable short-term sedation.

Alfaxalone

5–10 mg/kg, IV

10–20 mg/kg, IM

Similar effects to those of propofol IV, but higher doses effective IM. Larger IM dose volumes necessitate dividing into two or more injections.

Isoflurane

1%–5%

Routine gaseous agent; subanesthetic levels provide short-term sedation. Mask down or conscious (sedated) intubation possible in some species.

Sevoflurane

2%–7%

Very similar effects to those of isoflurane but recoveries appear to be faster. Preferred agent for critical or large reptiles.