ジクロルボス
ジクロルボス（しばしばDDVPと略される）は、歴史的に広域スペクトルの駆虫薬および外部寄生虫駆除薬として使用されてきた揮発性の高い**有機リン系**化合物です。 * **獣医学的用途**: 主に豚の経口駆虫薬（回虫、鞭虫、結節腸虫を標的とする）として、また小動物や施設のハエ駆除用の外部寄生虫駆除薬（例：「ノーペストストリップ」）として利用されます。 * **歴史的背景**: かつては犬、猫、馬の体内用として利用可能でしたが、これらの動物種においては、より新しく、安全で効果的な駆虫薬（マクロライド系やベンズイミダゾール系など）に完全に取って代わられています。 > **臨床のポイント**: ジクロルボスは揮発性が高いため、密閉空間の飛翔昆虫や外部寄生虫を制御するために、化学物質を空気中にゆっくりと放出する樹脂ストリップでの使用に特に適しています。
作用機序: 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.
動物種別の用量
- 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
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
- Concurrent use of other cholinesterase-inhibiting drugs, pesticides, or chemicals
- Allowing fowl access to medicated feed or manure from treated animals
有害事象
- Vomiting
- Tremors
- Bradycardia
- Respiratory distress
- Hyperexcitability
- Salivation
- Diarrhea
薬物相互作用
- 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.
モニタリング
- Efficacy (resolution of parasite burden)
- Signs of organophosphate toxicity (SLUDDE signs, tremors, respiratory distress)
過量投与
> **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 の薬剤リファレンスは、獣医療従事者向けの臨床意思決定支援を目的としており、専門的判断やメーカーの最新添付文書に代わるものではありません。