Chill Protocol for Anxious or Reactive Dogs

Dog displaying fear-related defensive behavior

The Chill Protocol is an at-home pre-visit medication protocol administered before a veterinary appointment. It is designed to reduce fear, anxiety, and aggressive behavior, helping make handling safer and less stressful for the dog, the family, and the veterinary team.

This page outlines the administration schedule and includes a dose calculator based on the dog’s body weight.

Use the dose calculator

For veterinary professionals only: The Chill Protocol must be prescribed and individualized by a veterinarian based on the patient’s overall health, current medications, potential contraindications, and the planned procedure.

What Is the Chill Protocol?

Developed at the Cummings School of Veterinary Medicine at Tufts University, the Chill Protocol combines three medications administered before the dog arrives at the veterinary practice: gabapentin, melatonin, and oral transmucosal acepromazine.

It may be considered for dogs whose fear or aggression makes physical examinations, blood collection, or certain noninvasive diagnostic procedures difficult.

Why Timing Matters

Timing is a key part of the protocol. The medications need time to take effect before the dog is exposed to the stress associated with travel and arrival at the veterinary practice.

Following the administration schedule and ensuring that the family understands each step are therefore essential to the protocol’s effectiveness.

Chill Protocol Administration Schedule

The Evening Before the Appointment

Gabapentin: 20–25 mg/kg PO

Administer gabapentin the evening before the scheduled appointment.

1–2 Hours Before the Appointment

Gabapentin: 20–25 mg/kg PO

Administer with melatonin:

  • Small dogs: 0.5–1 mg PO

  • Medium dogs: 1–3 mg PO

  • Large dogs: 5 mg PO

30 Minutes Before Arrival

Acepromazine: 0.025–0.05 mg/kg OTM

The 10 mg/mL injectable formulation is administered oral transmucosally using a syringe to allow absorption through the oral mucosa.

Abbreviations: PO means orally. OTM means oral transmucosal.

Chill Protocol Dose Calculator

Enter the dog’s body weight below to calculate the corresponding medication amounts. All results must be reviewed and adjusted by the prescribing veterinarian before any medication is administered.

Clinical Considerations Before Prescribing

  • The veterinarian must consider the patient’s overall health and determine whether the protocol is contraindicated or whether lower doses are appropriate.

  • Sedation, weakness, or incoordination may occur. The family should be informed, and the dog should remain supervised after administration.

  • The protocol generally lasts approximately four to six hours. Redosing may be required if the appointment is scheduled later in the day or if the patient will remain at the veterinary practice throughout the day.

  • Additional injectable medications may be required to provide adequate analgesia or sedation for more invasive procedures.