Anesthetic Dosage Table

Last Review Date: October 16, 2020

I.  Purpose/Scope

The purpose of this Standard Operating Procedure (SOP) is to provide a range of common anesthetics, sedatives, analgesic, and euthanasia agents that are available for species housed within LAR facilities.  The dosages and routes of administration are provided, as well as other pertinent information regarding their usage. These tables do not catalog all available drugs, nor dosages. If a PI wishes to utilize a drug or dosage not provided within these charts, the AV should be consulted. The PI should also be aware of the drug action, expected duration, as well as any adverse effects the drugs selected for use may produce.

II.  Policy

It is LAR policy to meet or exceed all federal, state, and local regulations and guidelines and to comply with all institutional policies and procedures as they apply to the use of animals in research.  Personnel must attend any applicable training in animal care and use, occupational health and safety, equipment operation, and SOPs prior to performing activities outlined in this SOP or work under trained personnel's direct supervision

III.  Procedures

The standards of anesthesia for laboratory animals have increased significantly. These standards include the use of balanced anesthesia, physiologic monitoring, and improved postoperative care.

Balanced anesthesia is a practice of anesthesia using a combination of drugs, each in an amount sufficient to produce the optimum desired effect with a minimum of undesirable or adverse effects; in other words, minimize the animal's risk while maximizing the animal's comfort and safety.

The objective of a balanced anesthetic plan is to keep the animal calm, minimize pain, and reduce the potential for adverse events associated with analgesic and anesthetic agents. These combinations allow a reduction in the dosage of one or both, and reducing the required flowrate of inhaled anesthetics.

Physiologic monitoring of the anesthetized animal requires the use of manual (auscultation, palpation, or visual techniques) or technologic monitoring of the heart rate, respiratory rate, oxygen saturation (if available), blood pressure (if available), and body temperature.  For short anesthetic events (≤ 30 minutes), this monitoring is not always feasible due to the selected anesthetic agent's short duration of action or the required rapidity to finish a quick procedure without an anesthetist. More prolonged procedures require the use of an anesthetic monitoring form to document intraoperative physiologic monitoring (required physiologic measurements every 10-15 minutes), pre- and intraoperative drugs (dosages and time given), as well as adjustments in anesthetic flow rates as they occur during the procedure. A second person should be available to provide anesthesia and documentation while surgery is being performed.

Postoperative monitoring for short-duration procedures (<30 minutes) consists of placing the animal in a cage (without bedding) that is placed half-on and half-off a heating pad to provide supplemental warming while the animal recovers from the anesthesia/sedation. If the animal remains heavily sedated, it should be placed in sternal recumbency. Once the animal is ambulatory, it may be replaced in its standard housing cage. Recovery from a short procedure should be less than 15 minutes.

Postoperative monitoring for animals that have undergone a long anesthetic event (surgery) is a more extensive process requiring documentation. After anesthesia is discontinued, the animal should be placed in an incubator or a cage (without bedding) on a warm-water circulating pad. If the animal remains sedate for a very long time, it should be placed in sternal recumbency (belly down) to maximize bilateral lung inflation. Physiologic monitoring should continue every 15 minutes until it is ambulatory.

Once the animal is ambulatory, it should be examined every hour for three hours to ensure it is eating and drinking normally. If normothermia has not been achieved once the animal is ambulatory, it should remain on heat support, and its temperature checked hourly until a normal body temperature is documented. Supplemental soft food placed on the cage floor should be provided to improve appetite and prevent weight loss during this phase of recovery. The use of SQ fluids should be considered during the preoperative planning phase to ensure proper hydration postoperatively. After three hours of satisfactory recovery and documented normothermia, the animal may be returned to its home cage and monitored a minimum of twice daily for three days (or otherwise specified in the AUP). Further monitoring will be defined in the AUP.

Anesthetic and postoperative monitoring forms should be kept in a binder in the animal housing room for the experiment's duration, for examination by the AV or LAR staff.

 

Mouse and Hamster Anesthetics and Analgesics

Inhaled Anesthetic
Agent Dosage DEA License Comments
Isoflurane Induction: 3-5%        Maintenance: 1-5%       No Administered via precision vaporizer & compressed O2 or open-drop method
Injectable Sedation Drugs/Combinations
Agent Dosage DEA License Comments
Fentanyl 0.8 mg/kg, IP Yes 4–6 hours
Ketamine|Medetomidine 50 mg/kg | 0.5 mg/kg, IP Yes 20-40 minutes
Ketamine|Xylazine 50 mg/kg | 10 mg/kg, IP Yes 20-30 minutes
Injectable Anesthetic Drug/Combinations
Agent Dosage DEA License Comments
Ketamine|Xylazine 80-100 | 7.5-16 mg/kg IP, IM Yes 20-30 minutes
Ketamine | Xylazine | Acepromazine 100 | 2.5 | 2.5 mg/kg IP, IM Yes 60-90 minutes
Ketamine|Medetomidine 75-150 | 0.5-1.0 mg/kg, SQ, IP, may mix in syringe Yes 50 minutes
Pentobarbital 50-90 mg/kg, IP Yes 20-40 minutes
Local Anesthetics
Agent Dosage DEA License Comments
Lidocaine (1-2%) 2-4 mg/kg, IM, SQ No Onset 5-10 minutes, Duration < 1 hour, may need to dilute to achieve appropriate volume for infiltration
Bupivicaine (0.5% Marcaine®) 1-2 mg/kg, SQ No Onset 15-30 minutes, Duration 4-8 hours, may need to dilute to achieve appropriate volume for infiltration
Reversal Agents for Xylazine, Medetomidine, Ketamine, and Acepromazine
Agent Dosage DEA License Comments
Yohimbine 0.2 mg/kg, IM, SQ No Partial reversal of Ketamine and Acepromazine
Atipamezole 5 mg for every 1 mg of Medetomidine No Medetomidine reversal
Atipamezole 1 mg for every 10 mg of Xylazine, IM, SQ No Xylazine reversal
Analgesics
Agent Dosage DEA License Comments
Buprenorphine (Buprenex®) 0.01-0.2 mg/kg, SQ, IP Yes 6-12 hours
Buprenorphine SR 2.2 mg/kg, SQ Yes 72 hours
Fentanyl 0.05 mg/kg, IP Yes 4-6 hours
Carprofen (Rimadyl®) 5 mg/kg, SQ, IP Yes 24 hours
Meloxicam (Metacam®) 1-2 mg/kg, PO, SQ No 24 hours
Ketoprofen (Ketofen®) 5 mg/kg, SQ No 12-24 hours
Ibuprofen Liquigel cap (opened and vortexed in 200 ml of water) 1 mg/ml, PO No Administered continuously *short duration use only*
Acetaminophen (Tylenol® Elixir)* 300 mg/kg or 2-4.5 mg/ml, PO No Administered continuously *short duration use only*
Injectable Euthanasia Agent
Agent Dosage DEA License Comments
Pentobarbital 390 mg/ml (Beuthanasia® or Euthasol®) 150 mg/kg IP Yes Terminal

* Not appropriate as the only post-surgical analgesic to be administered due to reduction in 
  water intake 24-28 hours following surgery

Rat and Degu Anesthetics and Analgesics

Inhaled Anesthetic
Agent Dosage DEA License Comments
Isoflurane Induction: 3-5%            Maintenance: 1-5% No Administered via precision vaporizer & compressed O2 or open-drop method with IACUC approval
Injectable Sedation Drugs/Combinations
Agent Dosage DEA License Comments
Fentanyl 0.8 mg/kg, IP Yes 4–6 hours
Ketamine|Medetomidine 50 mg/kg | 0.5 mg/kg, IP Yes 20-40 minutes
Ketamine|Xylazine 50 mg/kg | 10 mg/kg, IP Yes 20-30 minutes
Injectable Anesthetic Drug/Combinations
Agent Dosage DEA License Comments
Ketamine | Xylazine 40-80 | 5-10 mg/kg IP, IM Yes 30-45 minutes, to prolong anesthesia, supplement with 1/3 dose of Ketamine only. Provide thermal support
Ketamine | Xylazine | Acepromazine 100 | 2.5 | 2.5 mg/kg IP, IM Yes 45-60 minutes, to prolong anesthesia, supplement with 1/3 dose of Ketamine only
Ketamine | Medetomidine 60-90 | 0.5 mg/kg, IP Yes 30-40 minutes, to prolong anesthesia, supplement with 1/3 dose of Ketamine only. Provide thermal support
Pentobarbital 30-60 mg/kg, IP Yes 60-80 minutes Do not combine with opioids
Propofol 10 mg/kg, IV No 5-7 minutes. Titrate use. Must be given very slowly IV; rapid administration lowers blood pressure precipitously
Local Anesthetics
Agent Dosage DEA License Comments
Lidocaine (1-2%) 2-4 mg/kg, (max 7 mg/kg), SQ No Onset 5-10 minutes, Duration 0.5-1 hours
Bupivicaine (0.5% Marcaine®) 1-2 mg/kg (max 8 mg/kg), SQ No Onset 15-30 minutes, Duration 4-8 hours
Reversal Agents for Xylazine, Medetomidine, Ketamine, and Acepromazine
Agent Dosage DEA License Comments
Yohimbine 0.2 mg/kg, IM, SQ No Partial reversal of Ketamine and Acepromazine
Atipamezole 5 mg for every 1 mg of Medetomidine, IM, SQ No Medetomidine reversal
Atipamezole 1 mg for every 10 mg of Xylazine, IM, SQ No Xylazine reversal
Analgesics
Agent Dosage DEA License Comments
Buprenorphine (Buprenex®) 0.01-0.2 mg/kg, SQ, IP Yes 6-12 hours
Buprenorphine SR 1.2 mg/kg, SQ, IP Yes 72 hours
Fentanyl 0.05 mg/kg, IP, IM Yes 4-6 hours
Carprofen (Rimadyl®) 5 mg/kg, SQ, IP No 24 hours
Meloxicam (Metacam®) 1-2 mg/kg, PO, SQ No 24 hours
Flunixin (Banamine®) 1.1-2.5 mg/kg, SQ No 12-24 hours
Ketoprofen (Ketofen®) 5 mg/kg, SQ No 12-24 hours
Ibuprofen Liquigel cap (opened and vortexed in 200 ml of water) 40 mg/kg or 0.2 mg/ml, PO No Water administration
Acetaminophen (Tylenol® Elixir) 300 mg/kg or 2-4.5 mg/ml, PO No Water administration
Injectable Euthanasia Agent
Agent Dosage DEA License Comments
Pentobarbital 390 mg/ml (Beuthanasia® or Euthasol®) 150 mg/kg IP Yes Terminal

* Not appropriate as the only post-surgical analgesic to be administered due to reduction in
  water intake 24-28 hours following surgery

Neonatal Rodent Analgesics and Anesthetics

Inhaled Anesthetic
Agent Dosage DEA License Comments
Isoflurane Induction: 3-5%            Maintenance: 1-5%  No Administered via precision vaporizer and compressed O2. Open-drop method with IACUC approval.
Hypothermia

Hypothermia Method: Mouse and rat pups up to 6 days of age may be anesthetized by hypothermia when inhalant anesthesia is not feasible.

  • Hypothermia for induction: Place the pup in a nitrile glove finger and immerse the glove finger in crushed ice and water (2-3 °C or 35-37°F) up to the level of the head so that the head of the pup is visible. Anesthesia induction takes 5-8 minutes
  • Procedure: Remove the pup from the ice bath and place on a re-freezable ice pack. A piece of gauze or cloth should prevent direct contact of the pup's kin with the freezable ice pack. Duration of anesthesia on an ice pack is 15 minutes maximum
  • Hypothermia Recovery: Rapid warming should be avoided. Pups can be placed in a small incubator (32-35°C or 90-95°F) for gradual warming over 20-30 minutes. Once warmed for this time, circulating warm water blankets can be used until mobile with complete recovery taking 30-60 minutes. Once mobile, pups may be mingled with the litter to aid in covering the procedure smells on the pup, then the litter returned to the dam.
Injectable Anesthetic Drug/Combinations
Agent Dosage DEA License Comments
Ketamine | Xylazine 40-80 | 5-10 mg/kg IP Yes Injectable anesthetic in neonatal rodents is unpredictable and has a > 50% rate of mortality. Use of injectable anesthetics should only be considered in neonates >6 days and where gas anesthesia is not feasible
Pentobarbital 30-60 mg/kg, IP Yes Injectable anesthetic in neonatal rodents is unpredictable and has a > 50% rate of mortality. Use of injectable anesthetics should only be considered in neonates >6 days and where gas anesthesia is not feasible
Analgesics
Agent Dosage DEA License Comments
Morphine 5-10 mg/kg, SQ Yes 6 hours
Buprenorphine (Buprenex®) 0.05-0.2 mg/kg, SQ, IP Yes 6-8 hours
Fentanyl 0.05 mg/kg, IP Yes 4 hours

Snowshoe Hare Anesthetics and Analgesics

Inhaled Anesthetic
Agent Dosage DEA License Comments
Isoflurane Induction: 3-5%            Maintenance: 1-5% No Administered via precision vaporizer and compressed O2 or by open-drop method
Injectable Anesthetic Drug/Combinations
Agent Dosage DEA License Comments
Ketamine | Xylazine 35 | 5 mg/kg, SQ Yes 30-40 minutes, to prolong anesthesia, supplement with 1/3 dose of Ketamine only
Ketamine |Xylazine | Acepromazine 35 | 5 | 1 mg/kg IM Yes 45-60 minutes, to prolong anesthesia, supplement with 1/3 dose of Ketamine only
Ketamine | Xylazine | Butorphanol 35 | 5 | 0.1 mg/kg IM Yes To prolong anesthesia, supplement with 1/3 dose of Ketamine only
Ketamine | Diazepam 20-40 | 1-5 mg/kg, IM Yes To prolong anesthesia, supplement with 1/3 dose of Ketamine only
Injectable Sedatives
Agent Dosage and Route DEA License Expected Duration
Acepromazine 1-5 mg/kg, SQ, IM No 4 hours, light to moderate sedation without analgesia
Xylazine 0.5-3 mg/kg, SQ, IM No 30-60 minutes, moderate to profound sedation with mild analgesia
Alfaxalone 6 mg/kg, IM Yes 40 minutes, moderate sedation
Medetomidine 0.25-0.5 mg/kg, SQ, IM Yes 1-2 hours, moderate to deep sedation
Ketamine 25-50 mg/kg, IM, IV Yes 1 hour (IM), 15-20 minutes (IV), moderate sedation
Local Anesthetics
Agent Dosage and Route Use Comments
Lidocaine < 4 mg/kg (<0.4ml/kg of a 1% solution), infiltrate Local anesthesia Duration < 1 hour, may need to dilute to achieve appropriate volume for infiltration
Bupivacaine < 2 mg/kg (<0.8 ml/kg of a 0.25% solution, infiltrate Local anesthesia Duration 4-8 hours, may need to dilute to achieve appropriate volume for infiltration
Analgesics
Agent Dosage and Route DEA License Comments
Buprenorphine 0.01-0.05 mg/kg, SQ, IV Yes 6-12 hours
Buprenorphine SR 0.12 mg/kg SQ Yes 72 hours
Carprofen 2-4 mg/kg, SQ, PO No 12-24 hours
Meloxicam 0.2-1 mg/kg SQ, PO No 24 hours, Use high end of dose range for PO administration
Ketoprofen 1-3 mg/kg, SQ, IM No 24 hours
Reversal Agents for Xylazine, Medetomidine, Ketamine, Acepromazine, and Diazepam
Agent Dosage and Route DEA License Comments
Atipamezole (Antisedan®) 0.1-1.0 mg/kg, SQ, IM, IV No Reversal agent for Xylazine and Medetomidine
Yohimbine (Yobine®) 0.2-1.0 mg/kg, IM, IV No Partially reverses effects of Ketamine and Acepromazine
Injectable Euthanasia Agent
Agent Dosage DEA License Comments
Pentobarbital 390 mg/ml (Beuthanasia® or Euthasol®) 150 mg/kg IP Yes Terminal

 

Bird Anesthetics and Analgesics

Inhaled Anesthetic
Agent Dosage and Route DEA License Comments
Isoflurane Induction:3-5%  Maintenance: 1-5% No Administered via precision vaporizer and compressed O2 or by open-drop method
Injectable/Intranasal Sedatives
Agent Dosage and Route DEA License Comments
Midazolam (Versed®)

2 mg/kg, IN, IM

4-6 mg/kg for finch sized birds, IN

Yes Wide margin of safety. Sedative, muscle relaxant, anxiolytic, amnestic. Dosages are for sole drug use – no combinations
Diazepam (Valium®)

0.2-2 mg/kg, IN only

10-15 mg/kg IN only in finch size birds
Yes IM injection should be avoided; Use as a sole agent
Midazolam | Butorphanol 2 | 1-2 mg/kg, IM Yes For deeper sedation; may be mixed in the same syringe for administration
Local Anesthetics
Agent Dosage and Route DEA License Comments
Lidocaine ≤ 4 mg/kg SQ, topical No Duration < 1 hour, may need to dilute to achieve appropriate volume for infiltration
Bupivacaine 2 mg/kg SQ No Duration 4-8 hours, may need to dilute to achieve appropriate volume for infiltration
Reversal Agents for Midazolam, Diazepam, and Medetomidine
Agent Dosage and Route DEA License Comments
Flumazenil 0.05 mg/kg initially, if reversal incomplete after 10-15 minutes, repeat, IN, IM IV No Reversal agent for Diazepam and Midazolam, recovery from sedation is usually complete within 10-15 minutes
Atipamezole No Reversal agent for Xylazine and Medetomidine
Analgesics
Agent Dosage and Route DEA License Expected Duration
Butorphanol (opioid) 1-3 mg/kg, IN* Yes 2-3 hours, analgesic and sedative effects
Meloxicam (NSAID) 1-1.6 mg/kg, IM, PO No 12-24 hours
*Administer IN drugs into the nostrils over 5-10 seconds. Split the total dose between both nostrils.
  Release the bird and allow 7-10 minutes to reach maximum effect. Do not allow the bird to perch.
  Place on the floor of the cage.
Injectable Euthanasia Agent
Agent Dosage and Route DEA License Comments
Pentobarbital 390 mg/ml (Beuthanasia® or Euthasol®) 150 mg/kg IP Yes Terminal

 

NOTICE OF DISCLAIMER:  The information provided above is not intended to serve as a substitute for informed medical advice.  If you use any of the anesthetics, sedatives, or analgesic medications included in this table, seek veterinary consultation before usage. The University of Montana disclaims all liability arising from the misuse of this information.

References:

  • Sedation and Analgesia in Birds. Mans, DVM, DACZM. U of W, School of Veterinary Medicine.
  • Anesthesia for Companion Birds. Degernes, DVM, MPH, DABVP, NC State.2008
  • Anesthesia and Analgesia in Laboratory Animals, 2nd Fish et al.
  • Laboratory Animal Medicine, 3rd Academic Press.
  • Plumb's Veterinary Drug Handbook, 8th Plumb
  • Veterinary Anesthetic & Analgesic Formulary, 3rd University of Colorado.
  • Safety and Clinical Efficacy of Sustained-Release Buprenorphine for Post-Operative Analgesia in New Zealand White Rabbits. J Am Assoc Vet Med:
  • Manual of Rabbit Medicine and Surgery, Flecknell, 2000
  • Textbook of Rabbit Medicine. Butterworth-Heinemann, 2001
  • Buprenorphine for Pain Relief in Mice: Repeated Injections vs. Sustained-Release Depot Formulation. Lab Anim. 2015 Jul;49-87. Jirkof et al.
  • Postoperative Analgesia Due to Sustained-Release Buprenorphine, Sustained-Release Meloxicam, and Carprofen Gel in a Model of Incisional Pain in Rats. J Am Assoc Lab Anim Sci. 2016 May; 55(3): 300-305. Seymour et al.
  • Palatability and Treatment Efficacy of Various Ibuprofen Formulations in C57BL/6 Mice with Ulcerative Dermatitis. J Am Assoc Lab Anim Sci. 2012 Sep; 51(5): 609-615. Ezell et al.
  • Alfaxalone-Xylazine Anesthesia in Laboratory Mice. J Am Assoc Lab Anim Sci. 2019 Jan; 58(1): 30-39. Erickson et al.