モキシデクチン
Moxidectin
Semi-synthetic methoxime derivative of nemadectin
別名: Cydectin · ProHeart · Advantage Multi · Quest · ComboCare · Advocate · Bravecto Plus · Endectrid · Moxiclear · Prinovox · CL-301423 · Moxidectina · Moxidectinum
VetSheet 獣医チームが監修更新日 2026年4月5日エビデンスに基づく獣医学リファレンス
用量は獣医専門家向けの臨床参考資料です。必ず最新の医薬品情報および個別症例に基づいて確認してください。
動物種別用量
🌎 NA — North America🌍 EU — Europe
犬
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Prevention of heartworm disease, adult fleas, hookworms, roundworms, and whipworms (Advantage Multi) | 10 mg/kg imidacloprid with 2.5 mg/kg moxidectin once a month by topical administration | topical | q30d | — | 🌎 NA |
| Heartworm prevention, hookworms (ProHeart 6) | 0.05 mL of the constituted suspension/kg body weight (provides 0.17 mg moxidectin/kg) | SC | q6mo | — | 🌎 NA |
| Scabiocidal therapy | 0.25 mg/kg SC every 7 days for three treatments OR 0.4 mg/kg PO every 3-4 days for 3-6 weeks | SC/PO | q7d or q3-4d | 3-6 weeks | 🌎 NA |
| Generalized demodicosis | 0.2-0.4 mg/kg PO once a day | PO | q24h | Until parasitic cure (averages 112 days) | 🌎 NA |
| Treatment of canine sarcoptic mange | 10 mg/kg body weight imidacloprid and 2.5 mg/kg body weight moxidectin | topical | q14d | 3 occasions | 🌍 EU |
| Flea, lice, mite, nematode treatment and heartworm/angiostrongylosis prevention | 10 mg/kg body weight imidacloprid and 2.5 mg/kg body weight moxidectin | topical | monthly | Ongoing for prevention | 🌍 EU |
- Prevention of heartworm disease, adult fleas, hookworms, roundworms, and whipworms (Advantage Multi): For dogs 3-9 lb = 0.4 mL; 9.1-20 lb = 1 mL; 20.1-55 lb = 2.5 mL, 55.1-88 lb = 4 mL.
- Heartworm prevention, hookworms (ProHeart 6): Do not overdose growing puppies. Mix at least 30 minutes prior to use.
- Scabiocidal therapy: May cause toxicity in ABCB1 mutant genotype dogs.
- Generalized demodicosis: May cause toxicity in ABCB1 mutant genotype dogs.
- Treatment of canine sarcoptic mange: Apply via spot-on pipette.
- Flea, lice, mite, nematode treatment and heartworm/angiostrongylosis prevention: Frequent shampooing may reduce efficacy.
猫
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Prevention of heartworm disease, adult fleas, ear mites, hookworms, and roundworms (Advantage Multi) | 10 mg/kg imidacloprid/1 mg/kg moxidectin once a month by topical administration | topical | q30d | — | 🌎 NA |
| Feline Aelurostrongylosis (Aelurostrongylus abstrusus) | One to three topical applications of 1 mg/kg moxidectin (in combination with imidacloprid) | topical | 1-3 applications | — | 🌎 NA |
| Flea, mite, nematode treatment and heartworm prevention | 10 mg/kg body weight imidacloprid and 1.0 mg/kg body weight moxidectin | topical | monthly | Ongoing for prevention | 🌍 EU |
| Flea/tick control and heartworm/nematode prevention (Bravecto Plus) | 280 mg/ml fluralaner and 14 mg/ml moxidectin (volume based on weight) | topical | q12w for flea/tick control, q8w for heartworm prevention | Ongoing | 🌍 EU |
- Prevention of heartworm disease, adult fleas, ear mites, hookworms, and roundworms (Advantage Multi): For cats 2-5 lb = 0.23 mL; 5.1-9 lb = 0.4 mL; 9.1-18 lb = 0.8 mL.
- Flea, mite, nematode treatment and heartworm prevention: Apply via spot-on pipette. Severe effects may be seen if applied to cats with adult heartworm disease.
- Flea/tick control and heartworm/nematode prevention (Bravecto Plus): Not for use in kittens <9 weeks or cats <1.2 kg.
馬
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Gastrointestinal parasites (Oral Gel) | Dial in the weight of the animal on the syringe | PO | single dose | — | 🌎 NA |
| Mucosal stages of small strongyles | 400 micrograms/kg PO | PO | single dose | — | 🌎 NA |
- Gastrointestinal parasites (Oral Gel): Horses weighing more than 1250 lb require additional gel from a second syringe.
牛
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Internal and external parasites (Pour-On) | 1 mL (5 mg)/10 kg (22 lb) bodyweight applied directly to the hair and skin along the top of the back | topical | single dose | — | 🌎 NA |
| Internal and external parasites (Injectable) | 0.2 mg/kg [1 mL for each 110 lb (50 kg) of bodyweight] subcutaneously | SC | single dose | — | 🌎 NA |
羊
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Internal parasites | 0.2 mg/kg [1 mL per 11 lb (1 mL per 5 kg) bodyweight] PO (drench) | PO | single dose | — | 🌎 NA |
| Gastrointestinal helminthes in Camelids (NWC) | 0.2 mg/kg | PO | single dose | — | 🌎 NA |
- Gastrointestinal helminthes in Camelids (NWC): Regimen of choice for camelids.
ヤギ
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Internal parasites | Twice the sheep dose (0.4 mg/kg) | PO | single dose | — | 🌎 NA |
用量は獣医専門家向けの臨床参考資料です。必ず最新の医薬品情報および個別症例に基づいて確認してください。
概要
モキシデクチンは、小動物および大動物の獣医療で広く使用されている強力な第2世代マクロライド系（アベルメクチン/ミルベマイシン・サブクラス）抗寄生虫薬です。
主な薬理学的特徴は以下の通りです：
- 広域スペクトル：広範囲の体内線虫（回虫、鉤虫、鞭虫、犬糸状虫の幼虫）および体外節足動物（ノミ、ダニ、シラミ、ウシバエ幼虫）に対して有効です。
- 高脂溶性：モキシデクチンはイベルメクチンの約100倍の脂溶性を持ちます。これにより、組織への広範な分布、半減期の延長、および徐放性製剤（例：6ヶ月持続型の犬糸状虫予防注射薬）の実現が可能になります。
- ABCB1 (MDR1) の安全性：ABCB1-1∆遺伝子変異を持つ犬はマクロライド系薬物に敏感ですが、FDA承認の標準ラベル用量（スポットオンおよび経口の犬糸状虫予防）でのモキシデクチンは、これらの犬種に対しても一般的に安全とされています。ただし、適応外の高用量使用（毛包虫症の治療など）は重篤な神経毒性を引き起こす可能性があります。
スポットオン（イミダクロプリドとの合剤が多い）、徐放性注射液、経口ゲル、ポアオン（滴下）液など、さまざまな剤形で提供されています。
作用機序
Moxidectin exerts its antiparasitic effects by disrupting the neurological function of invertebrates:
- Glutamate-Gated Chloride Channels (GluCl): Moxidectin binds selectively and with high affinity to GluCl channels present in invertebrate nerve and muscle cells → increases membrane permeability to chloride ions → causes cellular hyperpolarization → results in flaccid paralysis and death of the parasite.
- GABA Receptors: It also enhances the release of gamma-aminobutyric acid (GABA) at presynaptic neurons, further blocking post-synaptic stimulation.
Mammalian Safety: Mammals do not possess GluCl channels. Furthermore, the P-glycoprotein (P-gp) efflux pump at the mammalian blood-brain barrier actively prevents moxidectin from entering the central nervous system, protecting mammalian GABA receptors from exposure.
安全性・警告
禁忌
- Hypersensitivity to the drug
- Dogs not tested for heartworm infection prior to use
- Sick, debilitated, or underweight dogs (specifically for the 6-month injectable)
- Female dairy cattle of breeding age
- Horses intended for food purposes
- Foals younger than 4 months of age
- Kittens < 9 weeks of age
- Dogs < 7 weeks of age
- Dogs with Class 4 heartworm disease
- Cats < 1.2 kg (for fluralaner combination)
- Breeding males (for fluralaner combination)
有害事象
- Dogs: Lethargy, vomiting, ataxia, anorexia, diarrhea, nervousness, weakness, polydipsia, pruritus
- Dogs (Injectable): Rare but serious reports of anaphylaxis, liver disease, autoimmune hemolytic disease, convulsions
- Cats: Recumbency (rare)
- Horses: Minimal at labeled doses; CNS depression and coma reported in foals at high doses
- Cattle: Minimal to nonexistent at labeled doses
- Transient pruritus at application site
- Erythema at application site
- Hypersalivation (if licked)
- Emesis and haematemesis
- Diarrhoea
- Pyrexia
- Tachypnoea
- Mydriasis
- Severe systemic reactions in cats with adult heartworm disease
注意事項
Heartworm Testing: Always test dogs for existing heartworm infections before initiating moxidectin therapy. Adult heartworms and microfilariae should be removed prior to therapy.
- ABCB1 (MDR1) Mutants: Safe at standard labeled preventative doses. However, off-label high doses (e.g., for demodicosis or scabies) can cause severe neurotoxicity in herding breeds with this mutation.
- Body Condition: Animals with very low body fat (neonates, cachexia) may experience significantly higher serum levels due to the drug's extreme lipophilicity, making them more prone to adverse reactions.
- Vaccinations: Caution is advised when administering the 6-month sustained-release injection concurrently with vaccinations, as anaphylaxis has been reported.
医薬品相互作用
Effects may be potentiated by moxidectin; concurrent use is generally not advised.
May inhibit the efflux pump at the blood-brain barrier, potentially increasing the risk of moxidectin neurotoxicity, especially in dogs with the ABCB1-1∆ mutation.
Increased risk of neurological toxicity due to competitive inhibition at the blood-brain barrier
Additive toxicity and increased risk of adverse neurological effects
監視
- Heartworm status prior to initiation of therapy
- Fecal egg count reduction testing (FECRT) in horses (target >95% reduction to monitor for resistance)
- Signs of neurotoxicity, especially in herding breeds or animals with low body fat
- Heartworm status (antigen/microfilariae testing) prior to initiating preventative therapy
- Resolution of clinical signs of parasitic infection
- Application site for erythema or pruritus
薬物動態
半減期
吸収
Highly lipophilic (100 times that of ivermectin).
分布
Volumes of distribution are very high due to extreme lipophilicity. Animals with very low body fat (neonates, cachexia) may have significantly higher serum levels than normal patients.
代謝
Hepatic metabolism (inferred from macrocyclic lactone class properties).
消失
Long duration of plasma residence (14-15 days in cattle). After SC injection in cows, approximately 5% of the dose can be passed to the suckling calf.
過剰投与
Moxidectin generally has a wide margin of safety when administered at labeled doses.
- Dogs: Dosages up to 300X (1120 mcg/kg) demonstrated little to no effects in normal dogs. However, in dogs with the ABCB1 (MDR1) mutant genotype, toxicity can be seen at doses as low as 90 mcg/kg.
- Clinical Signs of Toxicity: Dysorexia, hypersalivation, mydriasis, fasciculations, ataxia, tremors, seizures, vomiting, hyperesthesia, and recumbency/coma.
- Treatment: Supportive care. Intravenous fat emulsion (IVFE) has been successfully used to treat toxicity associated with macrocyclic lactones due to their highly lipid-soluble nature.
製品
製剤
- Sustained-release injection (microspheres)
- Topical solution (spot-on)
- Pour-on solution
- Injectable solution
- Oral drench
- Oral gel
- Topical spot-on: 10 mg/kg imidacloprid + 1.0 mg/kg moxidectin (Cats)
- Topical spot-on: 10 mg/kg imidacloprid + 2.5 mg/kg moxidectin (Dogs)
- Topical spot-on: 280 mg/ml fluralaner + 14 mg/ml moxidectin (Cats - Bravecto Plus)
動物用医薬品
- ProHeart 6: 10% Sustained-Release Injectable (598 mg/vial)
- Cydectin Pour-On for Cattle: 0.5% (5 mg/mL)
- Cydectin Injectable Solution: 10 mg/mL
- Cydectin Oral Drench for Sheep: 1 mg/mL
- Quest Oral Gel: 20 mg/mL
- Quest Plus Oral Gel: 20 mg/mL moxidectin + 125 mg/mL praziquantel
- Advantage Multi for Cats: 10 mg/mL moxidectin + 100 mg/mL imidacloprid
- Advantage Multi for Dogs: 25 mg/mL moxidectin + 100 mg/mL imidacloprid
- Advocate spot-on solution
- Bravecto Plus spot-on solution
- Endectrid spot-on solution
- Moxiclear spot-on solution
- Prinovox spot-on solution
規制ステータス
プール期間: cattle meat 14-65 days depending on formulation
POM-V classification.
POM-V classification.
規制データなし: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
保管・安定性
ProHeart 6: Store unconstituted product at or below 25°C (77°F) and protect from light. Once constituted, stable for 4 weeks under refrigeration at 2°-8°C (36°-46°F). Cydectin injection/drench: Store at or below 25°C (77°F) and protect from light. Cydectin Pour-on: Store at or below room temperature; do not freeze. Quest gel: Store at room temperature (59°F-86°F); avoid freezing.
飼主向け情報
- フィラリア（犬糸状虫）検査：この薬の投与を開始する前に、必ずフィラリア検査を受けてください。フィラリアに感染しているペットにこの薬を投与すると、重篤な反応を引き起こす可能性があります。
- 使用方法：スポットオン（滴下薬）を使用する場合は、ペットが舐められない首の付け根や肩甲骨の間の皮膚に直接（毛をかき分けて）塗布してください。塗布部位が乾くまでは、治療したペットを他のペットや子供から数時間遠ざけてください。
- 副作用：無気力、嘔吐、ふらつき（運動失調）、過度なよだれなどの兆候がないか観察してください。神経学的な異常が見られた場合は、直ちに獣医師に連絡してください。
- ProHeart 6（持続性注射薬）：愛犬が6ヶ月持続型の注射を受けた場合は、獣医師から提供される飼い主向け情報シートを必ず読み、注射後数日間はアレルギー反応（顔の腫れ、じんましん、重度の無気力など）の兆候がないか観察してください。
VetSheet医薬品リファレンスは獣医専門家の臨床意思決定支援を目的としており、専門的判断または製造業者の最新医薬品情報の代替にはなりません。