敵敵畏 / 二氯松
敵敵畏（通常縮寫為 DDVP）是一種高揮發性的**有機磷**化合物，歷史上被用作廣效驅蟲藥和體外寄生蟲殺滅劑。 * **獸醫用途**：主要用於豬隻的口服驅蟲（針對蛔蟲、鞭蟲和結節蟲），以及作為小型哺乳動物和環境蒼蠅控制的體外寄生蟲殺滅劑（例如「防蟲吊牌」）。 * **歷史背景**：雖然它曾經可用於狗、貓和馬的體內驅蟲，但在這些物種中，它已完全被更新、更安全且更有效的驅蟲藥（如巨環內酯類和苯并咪唑類）所取代。 > **臨床要點**：由於敵敵畏具有高揮發性，它非常適合用於樹脂吊牌中，將化學物質緩慢釋放到空氣中，以控制密閉空間內的飛蟲和體外寄生蟲。
作用機制: Dichlorvos acts by phosphorylating and inhibiting the enzyme **acetylcholinesterase (AChE)**. * **AChE Inhibition** → Prevents the breakdown of the neurotransmitter **acetylcholine (ACh)**. * **ACh Accumulation** → Continuous overstimulation of **nicotinic** and **muscarinic** receptors at the neuromuscular junction and autonomic synapses. * In susceptible parasites, this sustained depolarization leads to spastic paralysis and subsequent death. > **Pharmacological Note**: Organophosphate binding to AChE can become irreversible over time through a process called "aging." Prompt treatment of toxicity is required before aging occurs.
各物種劑量
- Internal parasites (Ascaris, Trichuris, Ascarops strongylina, Oesophagostomum spp.) · Specific amounts of feed per packet are dependent on pig weight. See the label for specific recommendations. · PO · Once · Single treatment · Administered by adding to feed (crumble-type or dry meal).
- Ectoparasite control · Hang 5 cm of a dichlorvos strip (e.g., Vapona No Pest Strip) 6 inches above cage for 24 hours, twice weekly for 3 weeks; OR hang in room for 24 hours once a week for 6 weeks; OR a 1 inch square laid on cage for 24 hours once a week for 6 weeks · Environmental · Twice weekly or once weekly · 3 to 6 weeks · For Mice, Rats, Gerbils, Hamsters, Guinea pigs, Chinchillas
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。
給藥途徑
禁忌症
- Concurrent use of other cholinesterase-inhibiting drugs, pesticides, or chemicals
- Allowing fowl access to medicated feed or manure from treated animals
不良反應
- Vomiting
- Tremors
- Bradycardia
- Respiratory distress
- Hyperexcitability
- Salivation
- Diarrhea
藥物相互作用
- Acepromazine (and other phenothiazines) · May potentiate organophosphate toxicity; should not be given within one month of worming with an organophosphate.
- Anticholinesterase drugs (e.g., neostigmine, physostigmine, pyridostigmine) · Additive cholinesterase inhibition; avoid concurrent use.
- DMSO (Dimethyl sulfoxide) · Has anticholinesterase activity; avoid concurrent use with organophosphates.
- Morphine · Can inhibit cholinesterase; avoid concurrent use.
- Pyrantel pamoate or tartrate · Adverse effects could be intensified if used concomitantly.
- Succinylcholine · Prolonged neuromuscular blockade; do not use depolarizing muscle relaxants for at least 48 hours after organophosphate administration.
監測
- Efficacy (resolution of parasite burden)
- Signs of organophosphate toxicity (SLUDDE signs, tremors, respiratory distress)
過量
> **Toxicity Warning**: Organophosphate overdosage causes severe cholinergic crisis, classically remembered by the acronym **SLUDDE** (Salivation, Lacrimation, Urination, Defecation, Dyspnea, Emesis). **Clinical Signs of Toxicity**: * Vomiting, diarrhea, and hypersalivation. * Muscle tremors, hyperexcitability, and seizures. * Bradycardia and severe respiratory distress (bronchoconstriction and increased secretions). **Treatment & Antidotes**: * **Atropine**: Acts as a muscarinic receptor antagonist to control life-threatening bradycardia, bronchoconstriction, and excessive secretions. * **Pralidoxime (2-PAM)**: An AChE reactivator that can reverse neuromuscular blockade (tremors/weakness) if administered before the enzyme-toxin complex "ages." * **Avoid**: Succinylcholine, theophylline, aminophylline, reserpine, or respiratory depressant drugs (e.g., narcotics, phenothiazines). * **Human Exposure**: If ingested by a human, immediately contact a poison control center, physician, or hospital emergency room.
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。