Atipamezole Hydrochloride Sterile Injectable Solution

Description

Atipamezole Hydrochloride Sterile Injectable Solution is a prescription veterinary medication indicated for the reversal of the sedative and analgesic effects of dexmedetomidine hydrochloride and medetomidine hydrochloride in dogs. It is administered intramuscularly following sedation with one of these alpha₂-adrenergic agonists.

Atipamezole hydrochloride is a synthetic alpha₂-adrenergic antagonist. By competitively blocking alpha₂ receptors, it counteracts the pharmacologic effects of dexmedetomidine or medetomidine and promotes recovery from sedation.

This product is intended for dogs only and requires a veterinary prescription. The appropriate dose is based on the dog's body surface area, body weight, and whether dexmedetomidine or medetomidine was originally administered intravenously or intramuscularly.

Uses & Benefits

• Reverses dexmedetomidine-induced sedation
• Reverses medetomidine-induced sedation
• Reverses the analgesic effects of dexmedetomidine and medetomidine
• Promotes recovery following alpha₂-agonist sedation
• Alpha₂-adrenergic antagonist
• Administered intramuscularly
• FDA-approved indication for dogs
• Allows veterinarian-controlled reversal of sedation and analgesia
• Helps reverse effects on heart rate, blood pressure, respiratory rate, and cardiac conduction associated with dexmedetomidine sedation

How It Works

Atipamezole hydrochloride is a selective alpha₂-adrenergic receptor antagonist.

Dexmedetomidine and medetomidine produce sedation and analgesia primarily through stimulation of alpha₂-adrenergic receptors. Atipamezole competitively blocks these receptors, counteracting the pharmacologic effects of the alpha₂ agonist and allowing the dog to recover from sedation.

Clinical studies have shown that atipamezole reverses dexmedetomidine's effects on blood pressure, respiratory rate, heart rate, and cardiac conduction times, although heart rate and conduction times may not immediately return to pre-sedation values.

Indications

For intramuscular use in dogs only.

Indicated for the reversal of:

• Dexmedetomidine hydrochloride-induced sedation / Dexmedetomidine hydrochloride-induced analgesia / Medetomidine hydrochloride-induced sedation / Medetomidine hydrochloride-induced analgesia

Ingredients

Active Ingredients:

• Atipamezole Hydrochloride – 5 mg/mL

Inactive Ingredients:

Inactive ingredients can vary by manufacturer. Current FDA-approved atipamezole hydrochloride injectable formulations may contain:

• Methylparaben – 1 mg/mL
• Sodium Chloride – 8.5 mg/mL
• Water for Injection

Some current generic formulations list sodium chloride but do not identify methylparaben in their inactive ingredient listing. Because Heartland notes that brands may vary, refer to the manufacturer label for the complete inactive ingredient information for the specific product dispensed.

Directions

Administer intramuscularly (IM) for reversal of sedation and analgesia, regardless of whether dexmedetomidine or medetomidine was originally administered intravenously or intramuscularly.

The appropriate atipamezole dose depends on the route used for the original sedative:

• Following IV dexmedetomidine or medetomidine: 3,750 mcg/m²
• Following IM dexmedetomidine or medetomidine: 5,000 mcg/m²

Dosage is calculated according to the dog's body surface area.

Weight / Dosage

Following IV Dexmedetomidine or Medetomidine – 3,750 mcg/m²

• 4–7 lb: 0.1 mL
• 7–9 lb: 0.15 mL
• 9–11 lb: 0.2 mL
• 11–22 lb: 0.3 mL
• 22–33 lb: 0.4 mL
• 33–44 lb: 0.5 mL
• 44–55 lb: 0.6 mL
• 55–66 lb: 0.7 mL
• 66–81 lb: 0.8 mL
• 81–99 lb: 0.9 mL
• 99–110 lb: 1.0 mL
• 110–132 lb: 1.1 mL
• 132–143 lb: 1.2 mL
• 143–165 lb: 1.3 mL
• 165–176 lb: 1.4 mL
• Greater than 176 lb: 1.5 mL

For reversal following IM dexmedetomidine or medetomidine, use the corresponding manufacturer dosing table for the 5,000 mcg/m² dose.

Administer exactly as prescribed by your veterinarian. Follow all dosing and administration instructions provided on the prescription label and by your veterinarian. Do not adjust the dose, frequency, route, or duration of administration unless directed by your veterinarian.

Cautions

• Federal law restricts this drug to use by or on the order of a licensed veterinarian.
• For intramuscular use in dogs only.
• Not for human use.
• Keep out of reach of children.
• Do not use in dogs with a known hypersensitivity to atipamezole.
• Because atipamezole is used with dexmedetomidine or medetomidine, it should not be used in dogs with cardiac disease, respiratory disorders, liver or kidney disease, shock, severe debilitation, or extreme stress due to heat, cold, or fatigue.
• The safety of atipamezole has not been evaluated in dogs with compromised health.
• Geriatric, debilitated, and ill dogs may have an increased risk of adverse reactions.
• Dogs with cardiovascular abnormalities may be at increased risk.
• Atipamezole has not been evaluated in dogs younger than 4 months or weighing less than 4.4 lb (2 kg).
• Additional procedures for pain control may be necessary because atipamezole also reverses the analgesic effects of dexmedetomidine and medetomidine.

Possible Side Effects

Possible adverse reactions following administration may include:

• Vomiting / Diarrhea / Hypersalivation / Trembling or muscle tremors / Excitement or hyperactivity / Panting / Increased urination / Inappropriate urination / Tachycardia or increased heart rate

Because reversal can occur rapidly, dogs should be appropriately monitored during recovery.

Contact a veterinarian immediately if a dog develops a severe or unexpected reaction following administration.

Precautions

• Use only under the direction of a licensed veterinarian
• Monitor the dog closely during recovery from sedation
• Heart rate, respiratory rate, blood pressure, body temperature, and overall recovery should be monitored as appropriate
• Maintain appropriate patient monitoring until recovery is considered adequate
• Consider the loss of analgesia when atipamezole is administered
• Additional pain-management measures may be required
• Use particular caution in geriatric, debilitated, or medically compromised dogs
• Not recommended for pregnant or lactating dogs or dogs intended for breeding because safety has not been evaluated
• Avoid accidental human exposure
• Atipamezole can be absorbed following exposure to the skin, eyes, or mouth
• In case of eye exposure, flush with water for 15 minutes
• In case of skin exposure, wash thoroughly with soap and water
• Seek medical attention following accidental injection or oral exposure

Storage

Store at controlled room temperature 20°C to 25°C (68°F to 77°F), with permitted excursions between 15°C and 30°C (59°F to 86°F). Storage and in-use requirements can vary by manufacturer. For example, Heartland's current Revertidine information directs users to discard unused product 28 days after first broaching the vial, while another current FDA-approved generic label specifies use within 90 days after first puncture and a maximum of 16 punctures. Follow the specific manufacturer label supplied with the product.

Disposal

Dispose of unused or expired medication, used needles, syringes, and empty vials according to applicable federal, state, and local requirements.

Needles and syringes should be placed in an appropriate sharps disposal container immediately after use. Do not reuse needles or syringes. Follow the specific manufacturer label and veterinary facility procedures for complete disposal requirements.