Doxapram

Doxapram is a short-acting respiratory stimulant used in selected veterinary patients with depressed ventilation. Applications include temporary stimulation during recovery from anesthesia, selected neonatal resuscitation situations and specialist assessment of laryngeal movement. Its effects reflect stimulation of respiratory drive and differ from the support provided by assisted ventilation.

Group

Respiratory stimulant

Mechanism of Action

Doxapram inhibits background potassium channels, including TASK-family channels, in carotid-body chemoreceptor cells. Depolarization increases afferent signaling to the brainstem respiratory centers and stimulates ventilation. At greater exposure, direct central effects also contribute. Increased respiratory rate and tidal volume can improve carbon dioxide elimination, while stimulation of respiratory effort can help reveal laryngeal movement during examination.

Dose Rates

Horse

Use / stage	Dose	Route	Schedule	Instructions
Foal respiratory support — Loading	0.5 mg/kg	IV		Neonatal foals.
Foal respiratory support — Maintenance	0.03–0.08 mg/kg/min	IV	Continuous	Following loading, infuse for 20 minutes.
Foal respiratory support	0.05–0.08 mg/kg/min	IV	Continuous	Alternative course initiated as an infusion and continued 8–12 hours.

Dog

Use / stage	Dose	Route	Schedule	Instructions
Respiratory stimulation	5–10 mg/kg	IV		Adult small-animal source regimen. Titrate to response; not a substitute for ventilation or resuscitation.
Historical neonatal respiratory stimulation	Reference only	SC, OTM, IV		Neonatal source amount is 1–5 mg per animal via SC, sublingual or umbilical vein. Patient-specific neonatal resuscitation requires airway and ventilation support; do not apply adult weight-based dosing.

Cat

Use / stage	Dose	Route	Schedule	Instructions
Respiratory stimulation	5–10 mg/kg	IV		Adult small-animal source regimen. Titrate to response; not a substitute for ventilation or resuscitation.
Historical neonatal respiratory stimulation	Reference only	SC, OTM, IV		Neonatal source amount is 1–5 mg per animal via SC, sublingual or umbilical vein. Patient-specific neonatal resuscitation requires airway and ventilation support; do not apply adult weight-based dosing.

Rabbit

Use / stage	Dose	Route	Schedule	Instructions
Respiratory depression	2–5 mg/kg	SC, IV	Every 0.25 h

Mouse

Use / stage	Dose	Route	Schedule	Instructions
Respiratory depression	5–10 mg/kg	IV

Rat

Use / stage	Dose	Route	Schedule	Instructions
Respiratory depression	5–10 mg/kg	IV

Gerbil

Use / stage	Dose	Route	Schedule	Instructions
Respiratory depression	5–10 mg/kg	IV

Hamster

Use / stage	Dose	Route	Schedule	Instructions
Respiratory depression	5–10 mg/kg	IV

Guinea Pig

Use / stage	Dose	Route	Schedule	Instructions
Respiratory depression	5 mg/kg	IV

Chinchilla

Use / stage	Dose	Route	Schedule	Instructions
Respiratory depression	2–5 mg/kg	IV

Bird

Use / stage	Dose	Route	Schedule	Instructions
Respiratory depression	5–10 mg/kg	IM, IV

Reptile

Use / stage	Dose	Route	Schedule	Instructions
Postanesthetic respiratory stimulation	5 mg/kg	IV

Cattle

Use / stage	Dose	Route	Schedule	Instructions
Neonatal primary apnea	2 mg/kg	IV		Do not use in: Prematurity with pulmonary immaturity, Clinical evidence of immature lungs; Asphyxic calves when intubation and ventilation are not feasible; oxygenation and ventilation remain essential.

Indications

Short-term stimulation of ventilation in selected dogs, cats or horses with drug-associated respiratory depression during or after anesthesia.
Adjunctive respiratory stimulation in selected depressed neonates after dystocia or cesarean delivery, with species- and condition-dependent evidence.
Specialist treatment of selected neonatal foals with depressed ventilation and respiratory acidosis.
Diagnostic stimulation of respiratory effort during laryngeal-function assessment in dogs.

Contraindications

Cardiac or respiratory arrest; ventilation and resuscitation are required.
Not a substitute for assisted ventilation.

Interactions

Theophylline or aminophylline may increase CNS excitation.

Adverse effects

CNS excitement, seizures, sweating and cardiovascular stimulation

Preparations

Preparation	Form	Strength	Route
Doxapram injection 20 mg/mL SC and sublingual neonatal use are source-described; species-specific selection is required.	Injection	20 mg / mL	IV, SC, OTM

Monitoring and Administration

Monitor ventilation, oxygenation and heart rate. Onset is rapid but the effect is brief.