ピペラジン
ピペラジンは、主に犬、猫、馬、豚、家禽の**回虫**感染症の治療に使用される狭域駆虫薬です。 * 胃腸炎を併発している動物や妊娠中の動物にも安全に使用できると考えられています。 * **臨床のポイント**: ピペラジンは成虫の回虫にのみ有効であり、鉤虫、鞭虫、条虫には効果がないため、ピランテル、フェンベンダゾール、マクロライド系などの新しい広域駆虫薬の登場により、現代の獣医療での使用は大幅に減少しています。 * 様々な塩の形態（クエン酸塩、アジピン酸塩、リン酸塩、六水和物、二塩酸塩）で提供されており、それぞれ有効成分であるピペラジン塩基の含有量が異なります。
作用機序: Piperazine exerts a **'curare-like' effect** on susceptible nematodes. * It acts as a **GABA receptor agonist** and blocks **acetylcholine** at the myoneural junction of the parasite. * This causes **flaccid paralysis** (narcotizing the worm), allowing the live, paralyzed worms to be passed out of the host's gastrointestinal tract with the feces. * In ascarids, it also inhibits succinic acid production.
動物種別の用量
- Treatment of ascarids · 45-65 mg of base/kg PO; 150 mg maximum · PO · once · Retreat in 2-3 weeks · Larval stages in tissues are not affected, necessitating retreatment
- Treatment of ascarids · 110 mg/kg PO · PO · once · Repeat in 21 days
- Treatment of ascarids · 100 mg/kg PO · PO · once · Repeat in 3 weeks
- Treatment of ascarids · 20-30 mg/kg PO once · PO · once
- Treatment of ascarids · 110 mg/kg (base) PO · PO · once · Repeat in 3-4 weeks · Retreating at 10-week intervals for P. equorum infections in young animals is recommended
- Treatment of ascarids · 200 mg/kg, PO · PO · once · Maximum of 80 grams in adults, 60 grams in yearlings, and 30 grams in foals
- Ascarids in poultry · 100-500 mg/kg PO once · PO · once · Repeat in 10-14 days · Not effective in psittacines
- Nematodes in raptors · 100 mg/kg · PO · once · Piperazine citrate
- Nematodes in parakeets and canaries · 0.5 mg/gram · PO · once · Piperazine citrate
- Ascaridia galli in poultry · 32 mg/kg (as base) (approximately 0.3 grams for each adult) · PO · once · Given in each of 2 successive feedings or for 2 days in drinking water · Citrate or adipate salts usually used in feed; hexahydrate in drinking water
- Ascaris suum and Oesophagostomum · 0.2-0.4% in the feed, or 0.1-0.2% in the drinking water · PO · once · Consume within 12 hours · Fasting or withholding water overnight may be beneficial. Retreat in 2 months. Safe in young animals and pregnancy.
- Ascaris suum and Oesophagostomum · 110 mg/kg (as base) · PO · once · Consume in 8-12 hours · Citrate salt usually used in feed as a one-day treatment, and hexahydrate in drinking water.
- Pinworms (Mice, rats, hamsters, gerbils, and rabbits) · Piperazine citrate in drinking water at 3 grams/liter · PO · continuous · 2 weeks
- Pinworms (Rabbits) · 100 mg/kg PO q24h · PO · q24h · 2 days · Piperazine citrate. Wash the perianal area.
- Pinworms (Rabbits) · Adults: 200-500 mg/kg PO q24h. Young rabbits: 750 mg/kg, PO once daily · PO · q24h · 2 days · Piperazine adipate. Wash the perianal area.
- Pinworms/tapeworms (Mice, Rats, Gerbils, Hamsters, Guinea pigs, Chinchillas) · 2-5 mg/mL drinking water · PO · continuous · 7 days, off 7 days and repeat · Piperazine citrate
- Treatment of ascarids · 45-65 mg of base/kg PO; for pups less than 2.5 kg: 150 mg maximum · PO · once · Retreat in 2-3 weeks · Larval stages in tissues are not affected, necessitating retreatment
- Treatment of ascarids · 110 mg/kg PO · PO · once · Repeat in 21 days
- Treatment of ascarids · 100 mg/kg PO · PO · once · Repeat in 3 weeks
- Treatment of ascarids · 20-30 mg/kg PO once · PO · once
- Nematodes · 40-60 mg/kg PO · PO · once · Repeat in two weeks · Follow with a fecal examination 14 days after the second dose. If positive, give a third dose and continue cycle until cleared.
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
- Chronic liver disease
- Chronic kidney disease
- Gastrointestinal hypomotility
- Chronic renal failure
- Hepatic impairment
- Heavy worm burdens (relative contraindication due to risk of intestinal impaction)
有害事象
- Diarrhea
- Emesis
- Ataxia
- Transient softening of feces (horses)
- Neurological signs at high doses (ataxia, tremors)
薬物相互作用
- Chlorpromazine · May precipitate seizures if used concomitantly (data conflicts, but caution is advised) · moderate
- Laxatives (Purgatives) · Not recommended; may eliminate piperazine from the GI tract before its full efficacy is established
- Pyrantel / Morantel · Antagonistic modes of action (pyrantel causes spastic paralysis, piperazine causes flaccid paralysis); should not be used together
- Pyrantel · Antagonistic mechanism of action (Pyrantel causes spastic paralysis, Piperazine causes flaccid paralysis) · major
- Morantel · Antagonistic mechanism of action · major
モニタリング
- Clinical and/or laboratory efficacy (fecal examinations)
- Adverse effects (neurological signs, GI upset)
- Fecal flotation (to confirm clearance of roundworms)
- Adverse neurological signs
過量投与
Piperazine generally has a wide margin of safety (oral LD50 of piperazine adipate in mice is 11.4 g/kg). However, acute massive overdosage can lead to **paralysis and death**. **Feline Toxicity:** In cats, adverse effects occur within 24 hours after a toxic dose is ingested. Clinical signs include: * Emesis, hypersalivation, dehydration * Weakness, dyspnea, depression * Muscular fasciculations of ears, whiskers, tail, and eyes * Rear limb ataxia, head-pressing * Positional nystagmus and slowed pupillary responses *(Many of these effects may also be seen in dogs after toxic ingestions.)* **Treatment:** * Symptomatic and supportive care. * If ingestion was recent, use of **activated charcoal** and a cathartic is suggested. * Intravenous fluid therapy. * Keep the animal in a quiet, dark place. * Recovery generally takes place within 3-4 days.
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。