ケトプロフェン
Ketoprofen
2-(3-benzoylphenyl)propanoic acid
別名: Ketofen · Anafen · Comforion Vet · ketoprofenum · RP-19583 · Ketoprofeno
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
監査済み v13 用量エビデンス
構造化された用量計算エビデンスAnti-inflammatory/analgesic (extra-label)
認証済み獣医師の確認が必要
- q12-24h
NA
必ず考慮する臨床コンテキスト (1)
- Ketoprofen injection should be stored below 25°C (77°F), with brief excursions permitted between 0°C and 40°C (32°F-104°F) and used within 4 months of first vial puncture. 13
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
ケトプロフェンは、イブプロフェン、ナプロキセン、カルプロフェンと構造的に関連する強力なプロピオン酸誘導体非ステロイド性抗炎症薬（NSAID）です。獣医学において、その強力な鎮痛、解熱、抗炎症作用のために利用されています。
主な薬理学的特徴：
- エナンチオマーのプロファイル：市販のケトプロフェンはラセミ体です。S(+)エナンチオマーは主に抗プロスタグランジン活性（および関連する消化管/腎毒性）に関与し、R(-)エナンチオマーは重大な消化管への影響なしに鎮痛作用を提供します。
- 対象動物：馬の筋骨格系の痛みに広く使用されており、一部の臨床医からは猫の短期鎮痛における第一選択のNSAIDと見なされています。犬、牛、豚、およびさまざまなエキゾチックアニマルにも使用されます。
- 臨床上のポイント：非常に有効ですが、ケトプロフェンは非選択的COX阻害薬です。そのため、特に小動物において、新しいCOX-2選択的NSAID（コキシブ系）と比較して、消化管潰瘍や腎毒性のリスクが高くなります。犬や猫での使用は通常、短期間（例：1〜5日）に制限されます。
作用機序
Ketoprofen exerts its effects primarily through the inhibition of the cyclooxygenase (COX) enzymes.
- Arachidonic Acid Cascade: Cell membrane phospholipids → Phospholipase A2 → Arachidonic Acid.
- COX Inhibition: Ketoprofen non-selectively blocks COX-1 and COX-2 enzymes. This prevents the conversion of arachidonic acid into prostaglandin precursors (endoperoxides), thereby halting the synthesis of pro-inflammatory and hyperalgesic prostaglandins (e.g., PGE2) and thromboxanes.
- LOX Inhibition (Theoretical): Ketoprofen purportedly has inhibitory activity on lipoxygenase (LOX), which would theoretically block the formation of leukotrienes. However, in vitro studies have not definitively confirmed this dual-inhibition activity at therapeutic doses in veterinary species.
- Central and Peripheral Action: By reducing peripheral prostaglandins, it decreases nociceptor sensitization. It also acts centrally to reduce fever by inhibiting prostaglandin synthesis in the hypothalamus.
安全性・警告
禁忌
- Known hypersensitivity to ketoprofen or other NSAIDs
- Active gastrointestinal ulceration or bleeding
- Significant renal or hepatic impairment
- Late pregnancy (due to risk of premature closure of the patent ductus arteriosus)
- Intra-arterial administration
- Dehydrated, hypovolaemic, or hypotensive patients
- Patients with pre-existing gastrointestinal disease
- Patients with blood clotting problems
- Pregnant animals
- Animals < 6 weeks of age
有害事象
- Horses: Gastric mucosal damage, GI ulceration, renal crest necrosis, mild hepatitis, injection site inflammation (IM)
- Dogs and Cats: Vomiting, anorexia, gastrointestinal ulceration, renal toxicity
- General: Masking of infection signs (inflammation, hyperpyrexia)
- Gastrointestinal signs (vomiting, diarrhea, anorexia)
- Gastrointestinal ulceration and bleeding
- Renal toxicity (especially in dehydrated/hypotensive patients)
- Hepatic accumulation (in patients with liver disease)
- Potential precipitation of cardiac failure (rare/unknown risk in animals)
注意事項
High Protein Binding: Because ketoprofen is highly protein-bound, patients with hypoproteinemia may have increased levels of free (active) drug, significantly increasing the risk of toxicity.
- GI and Renal Risks: Use only when potential benefits outweigh risks in patients with a history of GI ulceration or compromised renal/hepatic function.
- Masking Infection: May mask clinical signs of infection such as fever and inflammation. Use appropriate anti-infective therapy if a primary infectious process is present.
- Breeding Animals: Use with caution in breeding animals; effects on fertility and fetal health are not fully established. Avoid in late pregnancy.
- Administration Warnings: Avoid subcutaneous (SC) injections in horses. Do not administer intra-arterially in any species.
医薬品相互作用
Increased risk for nephrotoxicity.
Increased risk for bleeding.
Plasma levels of ketoprofen could decrease; increased likelihood of GI adverse effects (blood loss). Concomitant use is not recommended.
May increase risk for GI ulceration.
Concomitant administration significantly increases the risks for GI adverse effects and ulceration.
May increase risk for nephrotoxicity.
May increase NSAID levels.
Ketoprofen may reduce the saluretic and diuretic effects of furosemide.
Ketoprofen is 99% protein-bound and may displace other drugs, leading to increased serum levels and duration of action.
Serious toxicity has occurred when NSAIDs are used concomitantly; use with extreme caution.
May cause a significant increase in serum levels and half-life of ketoprofen.
Increased risk of severe gastrointestinal ulceration and renal toxicity. Do not administer concurrently or within 24 hours.
Increased risk of severe gastrointestinal ulceration and bleeding. Do not administer concurrently or within 24 hours.
Increased risk of nephrotoxicity.
監視
- Clinical efficacy (reduction in pain, lameness, or fever)
- Adverse effects (monitor for vomiting, diarrhea, melena, or anorexia)
- Baseline and periodic liver and renal function tests (BUN, Creatinine, ALT, AST) are recommended with long-term therapy
- Clinical signs of gastrointestinal ulceration (vomiting, melena, anorexia)
- Renal parameters (BUN, Creatinine, USG) especially in older or compromised patients
- Hepatic enzymes
- Hydration status and blood pressure
薬物動態
半減期
吸収
Rapidly and nearly completely absorbed after oral administration in rats, dogs, and humans. Presence of food or milk decreases oral absorption. Oral absorption is poor in horses. IV and IM areas under the curve are relatively equivalent in horses.
分布
Volume of distribution is low in adult horses, but higher in foals (doses may need to be 1.5X higher in neonates). Enters synovial fluid. Highly bound to plasma proteins (99% in humans, ~93% in horses).
代謝
Metabolized to a conjugated metabolite (primarily glucuronidation in dogs and horses). In cats, thioesterification is proposed as a major elimination mechanism.
消失
Eliminated via the kidneys both as a conjugated metabolite and unchanged drug.
過剰投与
As with any NSAID, overdosage can lead to severe gastrointestinal and renal toxicity.
- Dogs: The LD50 after oral ingestion is reported to be 2000 mg/kg, but exposures as low as 0.44 mg/kg have caused GI ulcers. Common clinical signs of toxic exposure include vomiting.
- Cats: Highly sensitive; have developed renal toxicity at doses as low as 0.7 mg/kg.
- Horses: Generally tolerate higher doses. Doses up to 11 mg/kg IV once daily for 15 days showed no toxicity. However, severe laminitis occurred at 33 mg/kg/day (15X label dose) for 5 days. At 55 mg/kg/day (25X label dose), horses developed anorexia, depression, icterus, abdominal swelling, gastritis, nephritis, and hepatitis.
Treatment:
- Decontamination: Emetics and/or activated charcoal are appropriate for recent oral exposures.
- GI Protection: Use of gastrointestinal protectants (e.g., omeprazole, sucralfate, misoprostol) is strongly warranted if GI effects are expected.
- Renal Protection: Aggressive IV fluid diuresis is warranted to support renal perfusion if renal effects are expected.
製品
製剤
- Veterinary Injection: 100 mg/mL, 10 mg/mL
- Veterinary Tablets: 5 mg, 10 mg, 20 mg
- Human Capsules: 50 mg, 75 mg
- Human Extended-Release Capsules: 100 mg, 150 mg, 200 mg
- Injectable: 1% solution
- Oral: 5 mg tablets
- Oral: 20 mg tablets
動物用医薬品
- Ketoprofen Injection: 100 mg/mL (Ketofen, generic)
- Ketoprofen Injection: 10 mg/mL (Anafen, Ketofen - Canada/UK)
- Ketoprofen Tablets: 5 mg, 10 mg, 20 mg (Anafen, Ketofen - Canada/UK)
- Ketofen 1% injection
- Ketofen 5 mg tablets
- Ketofen 20 mg tablets
ヒト用医薬品
- Ketoprofen Capsules: 50 mg, 75 mg
- Ketoprofen Extended-Release Capsules: 100 mg, 150 mg, 200 mg
- Oruvail
- Orudis
規制ステータス
プール期間: pig meat 4 days · cattle meat 4 days · cattle milk 0 hours · horse meat 28 days
POM-V classification.
POM-V classification.
規制データなし: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
保管・安定性
Oral capsules should be stored at room temperature in tight, light-resistant containers. Veterinary injection should be stored at room temperature.
飼主向け情報
ケトプロフェンは、ペットの痛み、炎症、発熱を軽減するために使用される薬です。
重要な安全上のガイドライン：
- 食事と一緒に与える：経口でケトプロフェンを与える場合は、胃の不調を減らすために食事と一緒に与えるのが最適です。
- 胃腸の問題に注意する：最も一般的な副作用は、嘔吐、食欲不振、下痢です。ペットが嘔吐したり、食事を食べなくなったり、黒いタール状の便や嘔吐物・便に血が混じっているのに気づいた場合は、すぐに薬の投与を中止し、獣医師に連絡してください。これらは胃潰瘍の兆候である可能性があります。
- 薬を混ぜないでください：獣医師の特別な指示がない限り、ケトプロフェンを服用している間は、アスピリン、イブプロフェン、または他の鎮痛薬（リマダイル、メタカム、デラマックスなど）を絶対に与えないでください。これらを混ぜると、致命的な胃出血や腎不全を引き起こす可能性があります。
- 指示に正確に従う：処方された以上に用量を増やしたり、頻繁に与えたりしないでください。犬や猫はNSAIDの過剰摂取に対して非常に敏感です。
- 水分補給が重要：腎臓を保護するために、ペットが常に新鮮な飲み水にアクセスできるようにしてください。
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