Phenylephrine
別名: Neo-Synephrine, AH-chew D, Little Colds Decongestant, Lusonal, Nasop, Sudogest PE, Sudafed PE, Pedia Care Children's Decongestant, Triaminic Thin Strips Cold, Minims Phenylephrine
- **Hospital Use**: Injectable phenylephrine is a potent cardiovascular drug that should only be used by veterinary professionals in a clinical setting where continuous blood pressure and ECG monitoring are available. - **Oral Products**: Over-the-counter human cold medications containing phenylephrine should **never** be given to pets without explicit veterinary instruction, as they often contain other toxic ingredients (like acetaminophen or decongestants) and can cause vomiting, hyperactivity, or heart rate changes. - **Accidental Ingestion**: If your pet accidentally ingests a product containing phenylephrine, contact your veterinarian or an animal poison control center immediately.
劑量必須由獸醫按你寵物的個別情況決定。切勿在沒有獸醫指導下給予人類藥物或其他寵物的處方藥。
用途
- To increase blood pressure by vasoconstriction in pronounced systemic vasodilation or when increasing myocardial contractility is disadvantageous (e.g., hypertrophic cardiomyopathy)
- As a constant rate infusion for profound vasodilation due to septic shock
- As a vasopressor in catastrophic stages of hypovolemic shock
- As a CRI to increase peripheral vascular resistance and mean arterial blood pressure
- Diagnosis of Horner's syndrome (denervation hypersensitivity)
- General use
- As a CRI to increase peripheral vascular resistance and mean arterial blood pressure
- As a constant rate infusion for profound vasodilation due to septic shock
- As a vasopressor in catastrophic stages of hypovolemic shock
- Diagnosis of Horner's syndrome (denervation hypersensitivity)
- Hypotension secondary to drugs or vascular failure
給藥方式
可能的副作用
- Reflex bradycardia
- CNS effects (excitement, restlessness, headache)
- Arrhythmias (rare)
- Severe extravasation injuries (tissue necrosis and sloughing)
- Hypertension
- Tachycardia
- Tissue necrosis and sloughing (if IV extravasation occurs)
注意事項與禁忌
- Severe hypertension
- Ventricular tachycardia
- Hypersensitivity to phenylephrine
- Do not apply topically once ophthalmic surgery has started (to avoid direct arterial absorption)
- > **WARNING**: Extravasation injuries with phenylephrine can be very serious, leading to necrosis and sloughing of surrounding tissue. IV sites must be routinely monitored. If extravasation occurs, infiltrate the ischemic area with 5-10 mg phentolamine in 10-15 mL of normal saline using a fine needle. - **Extreme Caution**: Use carefully in geriatric patients, and those with hyperthyroidism, bradycardia, partial heart block, or other heart disease. - **Not a Substitute for Fluids**: Phenylephrine is not a replacement for adequate volume therapy in patients with shock; hypovolemia must be corrected first. - **Pregnancy**: FDA Category C. Can cause contraction of the pregnant uterus and constriction of uterine blood vessels. Use with caution.
藥物相互作用
- Alpha-Adrenergic Blockers (phentolamine, phenothiazines, phenoxybenzamine): Higher dosages of phenylephrine may be required to attain a pressor effect if these agents have been used prior to therapy.
- Anesthetics, General (halogenated): Potentially may induce cardiac arrhythmias when used with halothane anesthesia.
- Atropine (and other anticholinergics): Block the reflex bradycardia caused by phenylephrine.
- Beta-Adrenergic Blockers: The cardiostimulatory effects of phenylephrine (seen at high doses) can be blocked.
- Digoxin: Use with phenylephrine may cause increased myocardium sensitization.
- Monoamine Oxidase (MAO) Inhibitors (e.g., amitraz, selegiline): Should not be used with phenylephrine because of a pronounced pressor effect.
- Oxytocin: When used concurrently with oxytocic agents, pressor effects may be enhanced.
- Sympathomimetic Agents (epinephrine): Tachycardia and serious arrhythmias are possible.
- Volatile anaesthetic agents: Increased risk of cardiac arrhythmias
- Oxytocic agents: Enhanced pressor effects leading to severe hypertension
常見問題
Phenylephrine用於寵物有甚麼用途？
- **Hospital Use**: Injectable phenylephrine is a potent cardiovascular drug that should only be used by veterinary professionals in a clinical setting where continuous blood pressure and ECG monitoring are available. - **Oral Products**: Over-the-counter human cold medications containing phenylephrine should **never** be given to pets without explicit veterinary instruction, as they often contain other toxic ingredients (like acetaminophen or decongestants) and can cause vomiting, hyperactivity, or heart rate changes. - **Accidental Ingestion**: If your pet accidentally ingests a product containing phenylephrine, contact your veterinarian or an animal poison control center immediately.
Phenylephrine對我的寵物安全嗎？
劑量必須由獸醫按你寵物的個別情況決定。切勿在沒有獸醫指導下給予人類藥物或其他寵物的處方藥。
本文僅供一般健康教育，不能取代專業獸醫意見。如寵物身體不適，請諮詢獸醫。