プロメタジン

動物種別の用量

用量は獣医療従事者向けの臨床リファレンスです。必ず最新の添付文書と個々の患者で確認してください。

投与経路

禁忌

• Hypovolemia or shock (due to hypotensive effects)
• Tetanus or strychnine intoxication (due to extrapyramidal effects)
• Human label black box warning: Contraindicated in children < 2 years old (fatal respiratory depression)
• Known hypersensitivity to phenothiazines
• Severe central nervous system depression
• Comatose patients
• Use with caution in patients with seizure disorders
• Use with caution in patients with severe hepatic or cardiovascular disease

有害事象

• Sedation or lethargy
• Anticholinergic effects (dry mouth, urinary retention, decreased GI motility)
• Hypotension (especially with rapid IV administration or in hypovolemic patients)
• Extrapyramidal signs (tremors, rigidity, torticollis) - rare but possible
• Sedation / Lethargy
• Dry mucous membranes (anticholinergic effect)
• Tachycardia
• Hypotension
• Paradoxical excitation (especially in cats)
• Gastrointestinal disturbances

薬物相互作用

• Antacids · May cause reduced GI absorption of oral phenothiazines.
• Antidiarrheal mixtures (e.g., Kaolin/pectin, bismuth subsalicylate) · May cause reduced GI absorption of oral phenothiazines.
• Atropine & other anticholinergics · May have additive anticholinergic effects when used with promethazine.
• CNS Depressant Agents (barbiturates, narcotics, anesthetics) · May cause additive CNS depression if used with phenothiazines.
• Epinephrine · Phenothiazines block alpha-adrenergic receptors; concomitant epinephrine can lead to unopposed beta-activity causing vasodilation and increased cardiac rate (epinephrine reversal). · major
• Metoclopramide · Phenothiazines may potentiate the extrapyramidal effects of metoclopramide.
• Monoamine Oxidase Inhibitors (MAOIs) · May potentiate extrapyramidal effects.
• Opiates · May enhance the hypotensive effects of phenothiazines; dosages may need to be reduced.
• Organophosphate Agents · Phenothiazines should not be given within one month of worming with these agents as their toxic effects may be potentiated.
• CNS Depressants (e.g., opioids, barbiturates, anesthetics) · Additive central nervous system depression and sedation. · major
• Anticholinergic agents (e.g., atropine, glycopyrrolate) · Additive anticholinergic effects (tachycardia, dry mouth, ileus). · moderate

モニタリング

• Clinical efficacy (resolution of vomiting or pruritus)
• Degree of sedation
• Hydration status (if vomiting persists)
• Heart rate and rhythm
• Blood pressure (especially with IV use)
• Level of consciousness / CNS status
• Respiratory rate

過量投与

Overdose may result in profound sedation, severe hypotension, or acute extrapyramidal clinical signs (e.g., torticollis, tremors, excessive salivation, rigidity). * **Treatment**: Supportive care is primary. Acute extrapyramidal signs have been successfully treated with injectable **diphenhydramine** in humans. Hypotension should be treated with IV fluids; avoid epinephrine due to the risk of epinephrine reversal (use alpha-agonists like phenylephrine if pressors are required).