解磷定 / 普拉肟
Pralidoxime
Pralidoxime chloride / 2-pyridine aldoxime methyl chloride
別名: Protopam · 2-PAM · Pralidoxime chloride · Pralidoxime mesilate · 2-pyridine aldoxime methyl chloride
由 VetSheet 獸醫團隊審訂更新於 2026年4月5日本內容以實證獸醫文獻為本
劑量為持牌獸醫專業人員的臨床參考。請務必對照最新藥品說明書及個別病患確認。
各物種劑量
🌎 NA — North America🌍 EU — Europe
狗
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Organophosphate toxicity | 10-20 mg/kg | IV/IM/SC | bid to tid | Until nicotinic signs resolve (usually 1-2 days) | 🌍 EU |
- Organophosphate toxicity: Administer IV very slowly over 15-30 minutes. Can also be given as a continuous rate infusion (CRI). Must be given in conjunction with atropine.
貓
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Organophosphate toxicity | 10-20 mg/kg | IV/IM/SC | bid to tid | Until nicotinic signs resolve (usually 1-2 days) | 🌍 EU |
- Organophosphate toxicity: Administer IV very slowly over 15-30 minutes. Must be given in conjunction with atropine.
劑量為持牌獸醫專業人員的臨床參考。請務必對照最新藥品說明書及個別病患確認。
概覽
解磷定（通常稱為2-PAM）是獸醫學中用於治療有機磷（OP）中毒的特效解毒劑。它用於逆轉與有機磷中毒相關的神經肌肉麻痺。
警告： 解磷定通常禁忌用於氨基甲酸酯（Carbamate）中毒，因為它可能會使臨床症狀惡化或無效。
臨床提示： 解磷定不易穿過血腦屏障；因此，它主要緩解周邊菸鹼受體症狀（肌肉震顫、無力、麻痺），但不能緩解中樞神經系統症狀。它必須始終與阿托品（Atropine）結合使用，阿托品可解決危及生命的毒蕈鹼受體症狀（心動過緩、支氣管收縮和SLUDGE症狀：流涎、流淚、排尿、排便、腸胃不適、嘔吐）。為了有效，解磷定必須在有機磷-酵素複合物發生「老化」（永久不可逆結合）之前儘早給藥，這通常發生在暴露後24-48小時內。
作用機制
Pralidoxime works by reactivating the acetylcholinesterase (AChE) enzyme that has been inactivated by organophosphate binding. It binds to the OP-AChE complex → cleaves the phosphate bond → releases the OP → restores the enzyme's ability to break down acetylcholine at the synaptic cleft.
Additionally, it directly detoxifies certain unbound OP molecules through chemical inactivation and retards the 'aging' of phosphorylated cholinesterase into a non-reactive, permanently damaged form.
安全性與警告
禁忌症
- Carbamate toxicity (can exacerbate toxicity)
- Poisoning by non-anticholinesterase compounds
- Hypersensitivity to pralidoxime
不良反應
- Tachycardia
- Muscle rigidity
- Transient neuromuscular blockade (if given too rapidly IV)
- Hypertension
- Hyperventilation
注意事項
Rapid IV Administration: Must be given slowly (over 15-30 minutes). Rapid intravenous injection can cause tachycardia, cardiac arrest, and paradoxical muscle rigidity or neuromuscular blockade.
- Timing is critical: Efficacy drops significantly if administered >24-48 hours post-exposure due to enzyme 'aging'.
- Renal Impairment: Use with caution and reduce dose in patients with renal failure, as the drug is primarily excreted unchanged in the urine.
- Concurrent Therapy: Always ensure adequate atropinization and airway management before or during pralidoxime administration.
藥物相互作用
May exacerbate organophosphate toxicity
Prolonged neuromuscular blockade due to cholinesterase inhibition
May exacerbate respiratory depression in OP toxicity
May exacerbate toxicity
監測
- Heart rate and rhythm (ECG)
- Respiratory rate and effort
- Resolution of muscle fasciculations and weakness
- Blood pressure
- Renal function (urine output)
藥物動力學
半衰期
吸收
Poorly absorbed orally; must be given parenterally. Peak plasma concentrations are reached rapidly after IM or SC injection.
分佈
Distributed primarily in extracellular fluid. It is a quaternary ammonium compound and does not readily cross the blood-brain barrier.
代謝
Metabolized in the liver to a small extent.
排除
Rapidly excreted in the urine, primarily as unchanged drug via active tubular secretion.
過量
Overdose can cause paradoxical neuromuscular blockade, muscle rigidity, tachycardia, and worsening of cholinergic signs. Treatment is supportive, including artificial ventilation if respiratory paralysis occurs.
可用產品
劑型
- Powder for reconstitution: 1 g vial (produces 50 mg/ml solution)
人用標示
- Protopam Chloride 1 g powder for injection
各地核准狀態
Human approved drug used extra-label in veterinary medicine.
Available as a POM (Prescription Only Medicine).
POM-V or POM depending on specific formulation.
暫無法規資料: 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Store intact vials at room temperature. Reconstituted solutions should be used promptly as they generally do not contain preservatives. Discard any unused portion.
飼主須知
解磷定是一種緊急解毒劑，專門在獸醫醫院環境中使用，用於治療某些殺蟲劑或農藥（有機磷）引起的嚴重中毒。
- 它透過將毒物從寵物體內的重要酵素上「解開」，幫助恢復正常的肌肉功能和呼吸。
- 它幾乎總是與另一種稱為阿托品的解毒劑一起給藥。
- 時間至關重要；這種藥物在接觸毒物後的最初24小時內給藥最為有效。
VetSheet 藥物參考供持牌獸醫專業人員作臨床決策輔助之用，不能取代專業判斷或廠方最新藥品說明書。