Brands, Medical Use, Clinical Data
Drug Category
- Central Nervous System Stimulants
- Respiratory System Agents
Dosage Forms
Brands / Synonyms
Dopram; Doxapram; Doxapram HCL; Doxapram hydrochloride; Stimulexin
Indications
For use as a temporary measure in hospitalized patients with acute respiratory insufficiency superimposed on chronic obstructive pulmonary disease.
Pharmacology
Doxapram is an analeptic agent (a stimulant of the central nervous system). The respiratory stimulant action is manifested by an increase in tidal volume associated with a slight increase in respiratory rate. A pressor response may result following doxapram administration. Provided there is no impairment of cardiac function, the pressor effect is more marked in hypovolemic than in normovolemic states. The pressor response is due to the improved cardiac output rather than peripheral vasoconstriction. Following doxapram administration, an increased release of catecholamines has been noted.
Mechanism of Action
Doxapram produces respiratory stimulation mediated through the peripheral carotid chemoreceptors.
Absorption
Not Available
Toxicity
Intravenous LD50 values in the mouse and rat were approximately 75 mg/kg and in the cat and dog were 40 to 80 mg/kg. Symptoms of overdosage are extensions of the pharmacologic effects of the drug. Excessive pressor effect, tachycardia, skeletal muscle hyperactivity, and enhanced deep tendon reflexes may be early signs of overdosage.
Biotrnasformation / Drug Metabolism
Not Available
Contraindications
Due to its benzyl alcohol content, doxapram injection is contraindicated in neonates.
Doxapram should not be used in patients with epilepsy or other convulsive disorders.
Doxapram is contraindicated in patients with mechanical disorders of ventilation such as mechanical obstruction,
muscle paresis, flail chest, pneumothorax, acute bronchial asthma, pulmonary fibrosis or other conditions resulting
in restriction of chest wall, muscles of respiration or alveolar expansion.
Doxapram is contraindicated in patients with evidence of head injury or cerebral vascular accident and in those
with significant cardiovascular impairment, severe hypertension, or known hypersensitivity to the drug or any of the
injection components.
Drug Interactions
Administration of doxapram to patients who are receiving sympathomimetic or monoamine oxidase inhibiting drugs may
result in an additive pressor effect .
In patients who have received muscle relaxants, doxapram may temporarily mask the residual effects of muscle
relaxant drugs.
In patients who have received general anesthesia utilizing a volatile agent known to sensitize the myocardium to
catecholamines, administration of doxapram should be delayed until the volatile agent has been excreted in order to
lessen the potential for arrhythmias, including ventricular tachycardia and ventricular fibrillation.
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