フルボキサミン
Fluvoxamine
Fluvoxamine maleate
別名: Luvox CR · Dumirox · Faverin · Fevarin · DU-23000 · desifluvoxamin · Dumyrox · Favoxil · Felixsan · Flox-ex · Floxyfral · Fluvohexal · Fluvoxadura · Fluvoxin · Maveral
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 |
|---|---|---|---|---|---|
| For treatment of compulsive disorders | 0.5-2 mg/kg PO twice daily | PO | q12h | — | 🌎 NA |
| For treatment of behavioral diagnoses | 1-3 mg/kg PO once daily (q24h) | PO | q24h | allow 8 weeks for initial trial | 🌎 NA |
| For treatment of behavioral diagnoses | 1 mg/kg PO q12-24h | PO | q12-24h | Treat for 3-5 weeks minimum to assess effects; then treat until 'well' (minimum another 1-2 months). Continue for another 1-2 months minimum. | 🌎 NA |
- For treatment of behavioral diagnoses: Treatment should last for a minimum 4-6 months once initiating therapy. If weaning off, do so over 3-5 weeks (or longer).
猫
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| For treatment of compulsive disorders | 0.25-0.5 mg/kg PO once daily | PO | q24h | — | 🌎 NA |
| For treatment of behavioral diagnoses | 0.25-0.5 mg/kg PO q24h | PO | q24h | Treat for 3-5 weeks minimum to assess effects; then treat until 'well' (minimum another 1-2 months). Continue for another 1-2 months minimum. | 🌎 NA |
| For spraying | 0.25 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
| For treatment of behavioral diagnoses | 0.5-1 mg/kg PO once daily (q24h) | PO | q24h | allow 8 weeks for initial trial | 🌎 NA |
- For treatment of behavioral diagnoses: Treatment should last for a minimum 4-6 months once initiating therapy. If weaning off, do so over 3-5 weeks (or longer).
- For spraying: Avoid use with benzodiazepines
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
フルボキサミンは選択的セロトニン再取り込み阻害薬（SSRI）であり、犬や猫の攻撃性や常同行動（強迫性障害）などの様々な行動障害の治療に使用されます。
フルオキセチンほど一般的には処方されませんが、行動管理の代替薬として機能します。
臨床上のポイント:
- 他のSSRIと同様に、神経受容体のダウンレギュレーションに時間がかかるため、完全な臨床効果が現れるまでに長期間（通常6〜8週間）の継続投与が必要です。
- 急に投与を中止すべきではありません。離脱症状を避けるため、3〜5週間かけて徐々に減量することが推奨されます。
- 食欲不振は犬でよく見られる副作用ですが（通常は一過性）、手から直接食べさせたり、食事の嗜好性を高めることで管理できる場合があります。
作用機序
Fluvoxamine acts by highly selective inhibition of the serotonin transporter (SERT) in the central nervous system.
Mechanism: Blockade of presynaptic reuptake → increased concentration of serotonin (5-HT) in the synaptic cleft → prolonged receptor stimulation. Over time, this chronic elevation leads to the down-regulation and desensitization of post-synaptic 5-HT receptors, which correlates with the delayed onset of clinical behavioral improvement. It has minimal to no effect on dopamine or norepinephrine reuptake.
安全性・警告
禁忌
- Patients with known hypersensitivity to fluvoxamine or other SSRIs
- Concurrent use of Monoamine Oxidase Inhibitors (MAOIs) such as selegiline or amitraz
- Concurrent use of cisapride
有害事象
- Anorexia/decreased appetite (common)
- Lethargy or sedation
- Gastrointestinal upset (vomiting, diarrhea)
- Anxiety, irritability, or agitation
- Insomnia or hyperactivity
- Panting (dogs)
- Changes in elimination patterns (cats)
- Paradoxical aggressive behavior in previously non-aggressive dogs
注意事項
Caution: Use with care in patients with severe cardiac, renal, or hepatic disease. Dosages may need to be reduced in patients with severe renal or hepatic impairment, or in geriatric patients.
- Pregnancy: FDA Category C. Animal studies in rats showed increased pup mortality at birth and decreased birth weights.
- Lactation: Fluvoxamine enters maternal milk, though it appears unlikely to be of significant clinical concern.
医薬品相互作用
Fluvoxamine may paradoxically decrease the clinical efficacy of buspirone.
Fluvoxamine may increase plasma levels of cisapride, leading to toxicity. Concurrent use is contraindicated.
May decrease or reverse the effects of SSRIs (useful in treating serotonin syndrome).
Fluvoxamine may increase diazepam (and other benzodiazepine) levels.
Fluvoxamine may increase the effects of diltiazem; bradycardia has been reported in humans.
High risk for serotonin syndrome; contraindicated. A 5-week washout is required after stopping fluvoxamine, and a 2-week washout if stopping the MAOI first.
Fluvoxamine may increase plasma levels of methadone, leading to toxicity.
Increased plasma levels of phenytoin possible.
Fluvoxamine may increase these beta-blockers' plasma levels; atenolol may be safer.
Fluvoxamine may increase plasma levels of theophylline.
SSRIs can inhibit the metabolism of tramadol to active metabolites, decreasing efficacy and increasing toxicity risk (serotonin syndrome, seizures).
Fluvoxamine may increase TCA blood levels and increase the risk for serotonin syndrome.
Fluvoxamine may increase the risk for bleeding.
監視
- Clinical efficacy (behavioral improvement)
- Adverse effects, particularly appetite and body weight
- Baseline liver function tests (consider re-testing as needed)
- ECG (consider baseline and re-test as needed)
薬物動態
半減期
吸収
In dogs, fluvoxamine appears to be completely absorbed. In humans, it is absorbed after oral administration with a bioavailability of around 50%. Food does not appear to affect absorption.
分布
In humans, it is widely distributed in the body and about 80% bound to plasma proteins.
代謝
Extensively metabolized in the liver to non-active metabolites.
消失
Eliminated primarily in the urine. In dogs, only about 10% of a dose is excreted unchanged in the urine.
過剰投与
Limited data exists for animals. Any dosage over 10 mg/kg can reportedly cause tremors and lethargy.
Clinical Signs of Overdose: Vomiting, somnolence/coma, tremors, diarrhea, hypotension, heart rate/rhythm disturbances (bradycardia/tachycardia, ECG changes), and seizures. Fatalities have been reported in human overdoses.
Treatment:
- Standard protocols for GI decontamination (drug adsorption/removal) for potentially dangerous overdoses.
- Symptomatic and supportive therapy.
- Serotonin Syndrome Management: Cyproheptadine (1.1 mg/kg PO or rectally) may be used as an adjunctive treatment to negate serotonin effects.
- Seizure Control: Diazepam may be used to treat seizures or other severe neurologic signs.
製品
製剤
- Oral tablets
- Oral extended-release capsules
ヒト用医薬品
- Fluvoxamine Oral Tablets: 25 mg, 50 mg, & 100 mg (Luvox®, generic)
- Fluvoxamine Oral Extended-release Capsules: 100 mg & 150 mg (Luvox CR®)
規制ステータス
規制データなし: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
保管・安定性
Commercially available tablets should be stored in tight containers at room temperatures of 15-30°C (59-86°F) and protected from high humidity.
飼主向け情報
- 忍耐が必要です: この薬はすぐには効果が現れません。行動の顕著な改善が見られるまで、通常6〜8週間の継続的な投与が必要です。
- 行動療法: フルボキサミンは、専門的な行動修正プログラムと併用することで最も効果を発揮します。
- 副作用: 食欲低下、無気力、嘔吐、または異常な行動（不安の増強や攻撃性など）に注意してください。ペットが全く食事をとらなくなった場合は、獣医師に連絡してください。
- 安全な保管: 子供や他のペットの手の届かない場所に厳重に保管してください。
- 急に服用を中止しないでください: 治療を中止する必要がある場合、離脱症状を防ぐために獣医師が徐々に減量する方法を指導します。
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