Zolazepam and Tiletamine
Zolazepam / Tiletamine
Also known as: Zoletil · Telazol · Tiletamine/Zolazepam · Zolazepam hydrochloride and Tiletamine hydrochloride
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 |
|---|---|---|---|---|---|
| General anaesthesia | 5-10 mg/kg | IV | single dose | Duration of anaesthesia is 20-60 minutes | 🌍 EU |
| General anaesthesia | 7-25 mg/kg | IM | single dose | Duration of anaesthesia is 20-60 minutes | 🌍 EU |
- General anaesthesia: Dose refers to the combined tiletamine/zolazepam (100 mg/ml). Adjust depending on degree of pain expected and depth required.
- General anaesthesia: Dose refers to the combined tiletamine/zolazepam (100 mg/ml). Adjust depending on degree of pain expected and depth required.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| General anaesthesia | 5-7.5 mg/kg | IV | single dose | Duration of anaesthesia is 20-60 minutes | 🌍 EU |
| General anaesthesia | 10-15 mg/kg | IM | single dose | Duration of anaesthesia is 20-60 minutes | 🌍 EU |
- General anaesthesia: Dose refers to the combined tiletamine/zolazepam (100 mg/ml). Adjust depending on degree of pain expected and depth required.
- General anaesthesia: Dose refers to the combined tiletamine/zolazepam (100 mg/ml). Adjust depending on degree of pain expected and depth required.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Zolazepam/Tiletamine (commonly known by trade names such as Zoletil or Telazol) is a combination injectable anesthetic agent widely used in veterinary medicine for general anesthesia in dogs and cats. It combines a dissociative anesthetic (tiletamine) with a benzodiazepine (zolazepam) to provide anesthesia with concurrent muscle relaxation.
Clinical Warning: The combined product should not be used as the sole anesthetic agent for painful operations. It lacks sufficient visceral analgesia and must be combined with an appropriate analgesic (e.g., opioids, NSAIDs).
Clinical Pearl: Recovery from this combination can be prolonged (2-6 hours) and sometimes rough or excitable, particularly in dogs given higher doses. Premedication (e.g., with alpha-2 agonists or phenothiazines, though noting interactions) often increases the smoothness of recovery. Recovery is generally more prolonged in cats than in dogs.
Mechanism of action
The drug is a 1:1 combination of two active principles with complementary mechanisms:
- Zolazepam: A benzodiazepine that enhances the activity of GABA (gamma-aminobutyric acid) → the major inhibitory neurotransmitter within the CNS. This provides sedative, anxiolytic, and muscle-relaxing actions, counteracting the muscle rigidity typically caused by dissociative agents.
- Tiletamine: A dissociative anesthetic (pharmacologically similar to ketamine) that antagonizes NMDA (glutamic acid) receptors → depresses certain cerebral regions (thalamus and cortex) while the limbic system remains active, generating a state of dissociative anesthesia.
Safety & warnings
Contraindications
- Severe cardiac disease
- Severe respiratory disease
- Hypertensive disease
- Renal insufficiency
- Pancreatic insufficiency
- Hepatic insufficiency
- Head trauma or intracranial tumours
- Pregnancy (crosses the placenta and causes fatal respiratory depression in neonates)
Adverse effects
- Excessive salivation (ptyalism)
- Muscle rigidity during recovery
- Prolonged and excitable recovery (especially in dogs at higher doses)
- Pain on intramuscular injection (particularly in cats)
- Respiratory depression (can be fatal in neonates)
- Hypothermia
Precautions
Human Safety Warning: Pregnant women should avoid handling the product.
- Recovery Environment: Following anesthesia, return to normal is progressive (2-6 hours). Animals must be kept in a calm, quiet environment. Avoid excessive noise and light.
- Patient Factors: Recovery may be significantly delayed in obese, old, or debilitated animals.
- Parasite Collars: Remove any antiparasitic collar 24 hours before anesthesia.
- Secretions: Excessive salivation can occur; consider administration of an anticholinergic (e.g., atropine or glycopyrrolate) to control this.
Drug interactions
Increased cardiorespiratory depression and increased hypothermic effect during the last phase of anesthesia.
Slows down the elimination of the anesthetics if used during the pre- or intraoperative period.
Monitoring
- Heart rate and rhythm
- Respiratory rate and depth
- Body temperature (monitor closely for hypothermia)
- Depth of anesthesia (jaw tone, palpebral reflex)
- Quality of recovery (monitor for excitation or rigidity)
Pharmacokinetics
Half-life
Absorption
Rapidly absorbed following intramuscular injection.
Distribution
Widely distributed; crosses the blood-brain barrier and the placenta.
Metabolism
Hepatic metabolism. Elimination of the anesthetics is slowed by concurrent use of chloramphenicol.
Elimination
Excreted primarily via the kidneys.
Overdose
Overdosage increases the risk of severe cardiorespiratory depression, prolonged anesthesia, and highly excitable or rough recoveries. Treatment is supportive, including mechanical ventilation if respiratory failure occurs, thermal support for hypothermia, and potentially benzodiazepine antagonists (flumazenil) for the zolazepam component, though this leaves the tiletamine unopposed.
Available products
Formulations
- Injectable powder for reconstitution: 50 mg/ml zolazepam + 50 mg/ml tiletamine (100 mg/ml total combined active ingredients)
Veterinary
- Zoletil 100 (50 mg/ml zolazepam + 50 mg/ml tiletamine powder for reconstitution)
Regulatory status
Marketed as Telazol in the US.
Marketed as Zoletil. POM-V classification.
POM-V. Subject to safe custody requirements.
No regulatory data for: 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store the un-reconstituted powder according to manufacturer instructions (usually room temperature). Once reconstituted, the solution should be stored in a refrigerator and used within the timeframe specified by the manufacturer (typically a few days).
Client information
This medication is an anesthetic used by your veterinarian to perform procedures on your pet.
- Recovery at Home: Your pet may be groggy, wobbly, or sleepy for several hours after coming home. Keep them in a warm, quiet, and dimly lit room away from stairs, other pets, and children.
- Behavioral Changes: Some pets (especially dogs) may whine, vocalize, or seem agitated as the medication wears off. This is a normal part of the recovery process, but contact your vet if it seems excessive.
- Feeding: Follow your veterinarian's specific instructions regarding when to offer food and water, as swallowing reflexes may be temporarily impaired.
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.