Tiletamine / Zolazepam
Tiletamine hydrochloride / Zolazepam hydrochloride
Also known as: Telazol · CI-634 · CL-399 · CN-54521-2 · CI-716
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Diagnostic purposes | 6.6-9.9 mg/kg | IM | Once | — | 🌎 NA |
| Minor procedures of short duration | 9.9-13.2 mg/kg | IM | Once | — | 🌎 NA |
| General anesthesia/restraint | 3-10 mg/kg IM or SC or 2-5 mg/kg IV | IM/SC/IV | Once | — | 🌎 NA |
| Aggressive (difficult to handle) dogs requiring more sedation | 1-2 mg/kg | IM | Once | — | 🌎 NA |
- Diagnostic purposes: Supplemental doses should be less than initial dose. Max total dose 26.4 mg/kg. Use Atropine 0.04 mg/kg concurrently.
- Minor procedures of short duration: Supplemental doses should be less than initial dose. Max total dose 26.4 mg/kg. Use Atropine 0.04 mg/kg concurrently.
- General anesthesia/restraint: Based upon the combination of drugs.
- Aggressive (difficult to handle) dogs requiring more sedation: Only if insufficient sedation from opioid, higher dose medetomidine, and midazolam.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Procedures such as dentistry, abscess treatment, foreign body removal | 9.7-11.9 mg/kg | IM | Once | — | 🌎 NA |
| Procedures requiring mild to moderate analgesia (lacerations, castration) | 10.6-12.5 mg/kg | IM | Once | — | 🌎 NA |
| Ovariohysterectomy and onychectomy | 14.3-15.8 mg/kg | IM | Once | — | 🌎 NA |
| General anesthesia/restraint | 3-10 mg/kg IM or SC or 2-5 mg/kg IV | IM/SC/IV | Once | — | 🌎 NA |
- Procedures such as dentistry, abscess treatment, foreign body removal: Max total dose 72 mg/kg. Use Atropine 0.04 mg/kg concurrently.
- Procedures requiring mild to moderate analgesia (lacerations, castration): Max total dose 72 mg/kg. Use Atropine 0.04 mg/kg concurrently.
- Ovariohysterectomy and onychectomy: Max total dose 72 mg/kg. Use Atropine 0.04 mg/kg concurrently.
- General anesthesia/restraint: Based upon the combination of drugs.
Small Mammals
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Chemical restraint (Gerbils) | 20 mg/kg IP (in combination with xylazine 10 mg/kg) | IP | Once | — | 🌎 NA |
| Chemical restraint (Mice) | 80-100 mg/kg | IM | Once | — | 🌎 NA |
| Chemical restraint (Rats) | 20-60 mg/kg | IM | Once | — | 🌎 NA |
| Chemical restraint (Hamsters/Gerbils) | 20-80 mg/kg | IM | Once | — | 🌎 NA |
| Chemical restraint (Guinea pig) | 10-80 mg/kg | IM | Once | — | 🌎 NA |
| Chemical restraint (Chinchillas) | 20-40 mg/kg | IM | Once | — | 🌎 NA |
| Immobilization/anesthesia (Hamsters) | 50-80 mg/kg | IP | Once | — | 🌎 NA |
| Chemical restraint (Gerbils) | 10-30 mg/kg | IP | Once | — | 🌎 NA |
| Immobilization (Mice) | 80 mg/kg | IP | Once | — | 🌎 NA |
| Light anesthesia (Rats) | 40 mg/kg | IP | Once | — | 🌎 NA |
| Immobilization (Guinea pigs) | 40-60 mg/kg | IM | Once | — | 🌎 NA |
| Prior to inhalation anesthesia (Small rodents) | 6-10 mg/kg | IM | Once | — | 🌎 NA |
- Prior to inhalation anesthesia (Small rodents): Advantages: better muscle relaxation, small volume, rapid induction. Disadvantages: increased secretions, variable recovery.
Ferrets
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Sedative/analgesic | 22 mg/kg IM combined with glycopyrrolate (0.01 mg/kg IM) | IM | Once | — | 🌎 NA |
| Sedative/analgesic | 22 mg/kg | IM | Once | — | 🌎 NA |
| Sedative/analgesic | Telazol (1.5 mg/kg) plus xylazine (1.5 mg/kg) | IM | Once | — | 🌎 NA |
| Sedative/analgesic | Telazol (1.5 mg/kg) plus xylazine (1.5 mg/kg) plus butorphanol (0.2 mg/kg) | IM | Once | — | 🌎 NA |
| Sedative/analgesic | 22 mg/kg | IM | Once | — | 🌎 NA |
- Sedative/analgesic: Rapid onset, but slow and rough recovery (3-4 hours)
- Sedative/analgesic: Telazol alone
- Sedative/analgesic: May reverse xylazine with yohimbine (0.05 mg/kg IM)
- Sedative/analgesic: May reverse xylazine with yohimbine (0.05 mg/kg IM)
Birds
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Anesthesia/Restraint (Ratites) | 5 mg/kg | IM/IV | Once | — | 🌎 NA |
Reptiles
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Facilitate handling and anesthesia (Large Snakes) | 3 mg/kg | IM | Once | — | 🌎 NA |
| Facilitate handling and anesthesia (Crocodilians) | 4-8 mg/kg | IM | Once | — | 🌎 NA |
| General anesthesia | 3-10 mg/kg | IM | Once | — | 🌎 NA |
| Sedation for minor procedures | 4-10 mg/kg | IM | Once | — | 🌎 NA |
| Sedation/tranquillization or to facilitate intubation | 5 mg/kg | IM | Once | — | 🌎 NA |
- Facilitate handling and anesthesia (Large Snakes): Administer 30-45 minutes prior to handling. Sedation may persist for up to 48 hours.
- General anesthesia: Lizards/snakes generally lower end; chelonians may require high end. Monitor closely for apnea.
- Sedation for minor procedures: At higher doses (15-40 mg/kg), recovery may be greatly prolonged.
- Sedation/tranquillization or to facilitate intubation: Repeat if needed. Higher doses (6 mg/kg) associated with very long recovery times, especially in chelonians (72 hours).
Horses
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Anesthesia induction | Xylazine 1.1 mg/kg IV, 5 minutes prior to Telazol at 1.65-2.2 mg/kg IV | IV | Once | — | 🌎 NA |
- Anesthesia induction: ARCI UCGFS Class 2 Drug
Cattle
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Induction agent for cattle, llamas/alpacas | Xylazine at 0.05-0.1 mg/kg IV, IM, then Telazol at 2-4 mg/kg IV (IM) | IV/IM | Once | — | 🌎 NA |
| Restraint/Anesthesia (Llamas) | 4.7-6 mg/kg | IM | Once | — | 🌎 NA |
Sheep
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Induction agent | Xylazine at 0.05-0.1 mg/kg IV, IM, then Telazol at 2-4 mg/kg IV (IM) | IV/IM | Once | — | 🌎 NA |
- Induction agent: Caution: xylazine can cause severe hypoxemia and pulmonary edema in sheep.
Goats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Induction agent | Xylazine at 0.05-0.1 mg/kg IV, IM, then Telazol at 2-4 mg/kg IV (IM) | IV/IM | Once | — | 🌎 NA |
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Tiletamine/Zolazepam (commonly known by the trade name Telazol®) is a widely used injectable anesthetic and tranquilizer combination in veterinary medicine. It is formulated as a 1:1 ratio of two distinct pharmacological agents:
- Tiletamine: A dissociative anesthetic chemically related to ketamine, providing profound analgesia and amnesia.
- Zolazepam: A benzodiazepine minor tranquilizer (diazepinone) that provides muscle relaxation, anxiolysis, and counteracts the muscle rigidity and seizure potential typically associated with dissociative anesthetics.
While officially FDA-approved for use in dogs and cats for restraint, minor procedures, and anesthesia, it is extensively used off-label across a vast array of species, including horses, ruminants, swine, birds, reptiles, and exotic/wildlife species.
Clinical Pearl: The duration of effect of the two components varies by species. In dogs, tiletamine outlasts zolazepam, leading to a shorter duration of tranquilization than anesthesia (potentially rougher recoveries). In cats, zolazepam outlasts tiletamine, resulting in a longer period of tranquilization during recovery.
Mechanism of action
The combination works synergistically through two distinct central nervous system pathways:
- Tiletamine acts as a non-competitive NMDA (N-methyl-D-aspartate) receptor antagonist. By blocking the excitatory neurotransmitter glutamate at the NMDA receptor → it prevents calcium influx into neurons → inducing a state of dissociative anesthesia characterized by catalepsy, profound somatic analgesia, and amnesia, while maintaining cranial nerve reflexes (e.g., palpebral, laryngeal).
- Zolazepam acts as a GABA-A receptor agonist. It binds to the benzodiazepine site on the GABA-A receptor complex → enhances the binding of the inhibitory neurotransmitter GABA → increases chloride ion influx → resulting in hyperpolarization of the neuron. This provides muscle relaxation, anxiolysis, and anticonvulsant effects, smoothing the induction and recovery phases of the dissociative anesthetic.
Safety & warnings
Contraindications
- Pancreatic disease
- Severe cardiac disease
- Severe pulmonary disease
- Rabbits (due to reports of renal toxicity/nephrosis)
- Large exotic cats, especially tigers (may cause seizures, permanent neurologic abnormalities, or death)
- Cesarean section (crosses placenta, causes fetal respiratory depression)
Adverse effects
- Respiratory depression and transient apnea
- Pain upon IM injection (especially in cats due to low pH)
- Athetoid movements (involuntary writhing/twitching)
- Tachycardia (especially in dogs)
- Emesis during emergence
- Excessive salivation and bronchial/tracheal secretions
- Vocalization and erratic/prolonged recovery
- Hypothermia
- Muscle rigidity or hypertonia
- Hypertension or hypotension
- Cyanosis, pulmonary edema, or cardiac arrest (rare/at high doses)
Precautions
Renal Dysfunction: Animals with renal disease may experience prolonged duration of anesthetic action or recovery times. Dosages may need reduction in geriatric or debilitated patients.
Hypothermia: May cause significant hypothermia. Susceptible animals (small body surface area, low ambient temperatures) must be monitored carefully and provided supplemental heat.
Reflexes Maintained: Like ketamine, Telazol does not abolish pinnal, palpebral, pedal, laryngeal, and pharyngeal reflexes. Use alone may not be adequate for surgery in these areas.
Ocular Protection: Cats' eyes remain open after administration. Protect from injury and apply an ophthalmic lubricant (e.g., Lacrilube) to prevent corneal drying.
Airway Management: Cats reportedly do not tolerate endotracheal tubes well with this agent alone.
Species Specific Warnings: Contraindicated in tigers and generally avoided in large exotic cats. Not recommended in rabbits due to nephrotoxicity.
Drug interactions
Dosage may need to be reduced when used concomitantly with Telazol.
Dosage may need to be reduced when used concomitantly with Telazol.
In cats, anesthesia is prolonged on average by 30 minutes. No apparent effect on recovery times in dogs.
Can cause increased respiratory and cardiac depression.
May cause enhanced or prolonged respiratory depression (extrapolated from ketamine).
May induce hypertension and tachycardia (extrapolated from ketamine).
May increase zolazepam (benzodiazepine) levels.
May increase zolazepam levels.
May increase zolazepam levels.
May increase zolazepam levels.
May increase hypnotic effects and risk of hypotension/respiratory depression.
May decrease peak levels and AUC of zolazepam.
May decrease peak levels and AUC of zolazepam.
Monitoring
- Level of anesthesia and analgesia
- Respiratory function (rate, depth, pulse oximetry)
- Cardiovascular status (heart rate, rhythm, blood pressure)
- Body temperature (monitor for hypothermia)
- Eye moisture and corneal integrity (especially in cats)
Pharmacokinetics
Half-life
Absorption
Onset of action is variable but generally rapid. In cats, IM onset is 1-7 minutes. In dogs, IM onset averages 7.5 minutes.
Distribution
Crosses the placenta.
Metabolism
Hepatic metabolism. The duration of effect of the two components varies by species (zolazepam lasts longer in cats; tiletamine lasts longer in dogs).
Elimination
Less than 4% of the drugs are excreted unchanged in the urine in dogs.
Overdose
The manufacturer claims a 2X margin of safety in dogs and a 4.5X margin of safety in cats.
- Clinical Signs: Excessive respiratory depression, prolonged anesthesia, potential cardiovascular collapse.
- Treatment: In massive overdoses, mechanically assisted ventilation should be performed if necessary. Treat other clinical signs symptomatically and supportively.
- Reversal/Stimulation: A preliminary study in dogs suggests that doxapram at 5.5 mg/kg will enhance respirations and arousal after Telazol administration.
Note: High doses of tiletamine have caused acute tubular necrosis in New Zealand white rabbits.
Available products
Formulations
- Injectable lyophilized powder for reconstitution: 50 mg/mL tiletamine + 50 mg/mL zolazepam (100 mg/mL combined)
Veterinary
- Telazol® (Pfizer): Tiletamine HCl (equivalent to 250 mg free base) and Zolazepam HCl (equivalent to 250 mg free base) as lyophilized powder in 5 mL vials. Reconstituted with 5 mL sterile water yields 50 mg/mL of each drug (100 mg/mL combined). (Rx, C-III)
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
After reconstitution, solutions may be stored for 4 days at room temperature and 14 days if refrigerated. Do not use solutions that contain a precipitate or are discolored.
Client information
This medication is an injectable anesthetic and tranquilizer used exclusively by veterinary professionals in a clinical setting to safely sedate or anesthetize your pet for procedures.
- Recovery: Your pet may experience a prolonged or slightly rough recovery period (vocalization, twitching, or grogginess) as the medication wears off. This is normal, but keep them in a quiet, safe, and warm environment until they are fully recovered.
- Eye Care: Because this medication can keep the eyes open during sedation, your veterinarian will apply a protective eye ointment. You may notice some ointment residue around the eyes after the procedure.
- Temperature: The drug can lower body temperature, so your pet may need extra warmth during recovery.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.