DOSAGE & ADMINISTRATION
It is recommended that dogs and cats be fasted for 12 hours before treatment with Dexdomitor. An eye lubricant should be applied to prevent corneal desiccation that may occur during sedation. Following injection of Dexdomitor, the animal should be allowed to rest quietly for 15 minutes; sedation and analgesia occur within 5 to 15 minutes, with peak effects at 20 to 30 minutes after Dexdomitor.
Dexdomitor produces sedation and analgesia when administered intramuscularly (IM) at a dose of 500 mcg/m2, or intravenously (IV) at a dose of 375 mcg/m2. Doses for preanesthesia are 125 or 375 mcg/m2 IM. The choice of preanesthetic dose depends on the duration and severity of the procedure, as well as the anesthetic regime. The following two tables may be used to determine the correct dexmedetomidine hydrochloride dosage. Note that the mcg/kg dosage decreases as body weight increases. For example, dogs weighing 2 kg are dosed at 28 mcg/kg dexmedetomidine hydrochloride IV, compared to dogs weighing 80 kg that are dosed at 9 mcg/kg.
Due to the small volume of administration, accurate dosing is not possible in dogs weighing less than 2 kg. The use of Dexdomitor Sterile Injectable Solution as a preanesthetic markedly reduces anesthetic requirements. Injectable induction drug requirements for intubation will be reduced between 30% and 60%, depending on the choice of anesthetic and the Dexdomitor preanesthetic dose. The concentration of inhalation maintenance anesthetic will be reduced between 40% and 60%, depending on the dose of Dexdomitor.
The anesthetic dose should always be titrated against the response of the patient. The choice of anesthetic is left to the discretion of the veterinarian.
Dexdomitor produces sedation and analgesia when administered IM at a dose of 40 mcg/kg. This dose can also be used as a preanesthetic and has been shown to reduce anesthetic requirements in cats. Injectable anesthetic drug requirements for intubation were reduced up to 49%, depending on the choice of induction drug. The concentration of inhalation maintenance anesthetic was reduced between 35% and 44%, depending on the choice of induction drug. The anesthetic dose should always be titrated against the response of the patient.
CONTRAINDICATIONS & WARNINGS
Do not use Dexdomitor in dogs or cats with cardiovascular disease, respiratory disorders, liver or kidney diseases, or in conditions of shock, severe debilitation, or stress due to extreme heat, cold or fatigue. Do not use in cases of known hypersensitivity to the active substance or to any of the excipients.
Dexdomitor in cats has not been evaluated in the presence of other sedatives. Although not observed in the feline field studies with Dexdomitor, rare cases of delayed pulmonary edema, some resulting in death, have been reported in cats that received Dexdomitor. In these cases, dyspnea due to the delayed onset of pulmonary edema developed up to three days after Dexdomitor administration. Dexdomitor should not be administered in the presence of preexisting hypotension, hypoxia, or bradycardia. Due to the pronounced cardiovascular effects of Dexdomitor, only clinically healthy dogs and cats should be treated. Animals should be frequently monitored for cardiovascular function and body temperature during sedation or anesthesia.
Intramuscular Antisedan (atipamezole hydrochloride) may be routinely used to rapidly reverse the effects of Dexdomitor in dogs. Since analgesic as well as sedative effects will be reversed, pain management may need to be addressed. Atipamezole has not been evaluated as a routine dexmedetomidine reversal agent in cats. Apnea may occur with Dexdomitor use. The risk is increased when Dexdomitor is used in conjunction with ketamine in cats. In the event of apnea, additional oxygen should be supplied. Administration of Antisedan (atipamezole hydrochloride) to dogs is warranted when apnea is accompanied by bradycardia and cyanotic mucous membranes. Anesthetic safety is increased when supplemental oxygen is given by mask or endotracheal tube to cats and dogs anesthetized with intravenous regimes, and this applies to the use of Dexdomitor as well. A decrease in body temperature is likely to occur during sedation with Dexdomitor Sterile Injectable Solution unless externally maintained. Once established, hypothermia may persist longer than sedation and analgesia. To prevent hypothermia, treated animals should be kept warm and at a constant temperature during the procedure, and until full recovery.
Nervous or excited animals with high levels of endogenous catecholamines may exhibit a reduced pharmacological response to alpha2-adrenoreceptor agonists like dexmedetomidine. In agitated animals, the onset of sedative/analgesic effects could be slowed, or the depth and duration of effects could be diminished or nonexistent. Therefore, allow dogs and cats to rest quietly for 10 to 15 minutes after injection. Repeat dosing has not been evaluated.
Reversible corneal opacity may occur during sedation. An eye lubricant should be applied to prevent corneal desiccation that may result from a reduction in the blink reflex or decrease in tear production during sedation. Spontaneous muscle contractions (twitching) can be expected in some dogs sedated with Dexdomitor. The use of Dexdomitor as a preanesthetic in dogs and cats significantly reduces the amount of induction and maintenance anesthetic requirements. Careful patient monitoring during anesthetic induction and maintenance is necessary to avoid anesthetic overdose. Analgesia resulting from preanesthetic Dexdomitor is dose-dependent, and may not provide adequate pain control during the postoperative or postprocedural period. Additional pain management should be addressed as needed. Administration of anticholinergic agents in dogs at the same time or after Dexdomitor could lead to adverse cardiovascular effects (secondary tachycardia, prolonged hypertension, and cardiac arrhythmias 2, 3, 4). However, an anticholinergic drug may be administered at least 10 minutes before Dexdomitor for the prevention of the Dexdomitor-induced reduction in heart rate. Therefore, the routine use of anticholinergics simultaneously with, or after Dexdomitor in dogs, is not recommended.
The use of anticholinergics in the presence of Dexdomitor has not been thoroughly evaluated in cats. Hypertension and a possible increase in myocardial workload may result from concurrent Dexdomitor and anticholinergic in cats, and the risk/benefit of anticholinergic use should be considered. Routine anticholinergic use is not recommended.
Dexdomitor Sterile Injectable Solution has been evaluated only in fasted dogs; therefore, its effects on fed dogs (for example, the occurrence of vomiting) have not been characterized. In cats, there is a high frequency of vomition whether fed or fasted; therefore, fasting is recommended to reduce stomach contents. Dexdomitor has not been evaluated in dogs younger than 16 weeks of age, in cats younger than 12 weeks of age, or in geriatric dogs and cats. Dexdomitor has not been evaluated for use in breeding, pregnant, or lactating dogs or cats.
Keep out of reach of children. Not for human use. See labels for complete warnings.