トブラマイシン
Tobramycin
Tobramycin sulfate
別名: TOBI · Brulamycin · Gernebcin · Mytobrin · Tobrex · tobramycin sulphate · Tobramycinum
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 |
|---|---|---|---|---|---|
| General susceptible infections | 2 mg/kg | IV, IM, SC | q8h | — | 🌎 NA |
| Susceptible UTI | 1-2 mg/kg | SC | q8h | — | 🌎 NA |
| Sepsis | 2-4 mg/kg | IV | q8h | — | 🌎 NA |
| Soft tissue, systemic infections | 1-1.7 mg/kg IV q8h or 3-5.1 mg/kg IV q24h | IV | q8h or q24h | < 7 days | 🌎 NA |
| Systemic infections | 2 mg/kg SC q8-12h or 4-6 mg/kg SC q24h | SC | q8-12h or q24h | < 7 days | 🌎 NA |
| Persistent bacteremia | 3-5 mg/kg IV, IM, SC q8h or 9-15 mg/kg IV, IM or SC q24h | IV, IM, SC | q8h or q24h | <= 7 days | 🌎 NA |
| Gram-negative infections | 4-6 mg/kg | IV/IM/SC | q24h | Assess according to clinical response | 🌍 EU |
- General susceptible infections: Avoid use or reduce dosage in patients with renal failure; recommend therapeutic drug monitoring, particularly in young animals. Consider consolidating to once-daily dosing (e.g., 6 mg/kg q24h).
- Gram-negative infections: For severe infections (including sepsis), doses as high as 12 mg/kg/day have been advocated, but should be used with caution given potential adverse effects.
猫
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| General susceptible infections | 2 mg/kg | IV, IM, SC | q8h | — | 🌎 NA |
| Susceptible UTI | 1-2 mg/kg | SC | q8h | — | 🌎 NA |
| Sepsis | 2-4 mg/kg | IV | q8h | — | 🌎 NA |
| Soft tissue, systemic infections | 2 mg/kg IV, IM or SC q12h or 4 mg/kg IV, IM, SC q24h | IV, IM, SC | q12h or q24h | <= 5 days | 🌎 NA |
| Persistent bacteremia | 2 mg/kg IV, IM, SC q8h or 6 mg/kg IV, IM or SC q24h | IV, IM, SC | q8h or q24h | <= 5 days | 🌎 NA |
| Gram-negative infections | 4-6 mg/kg | IV/IM/SC | q24h | Assess according to clinical response | 🌍 EU |
- General susceptible infections: Consider consolidating to once-daily dosing.
- Gram-negative infections: Cats may be more sensitive to toxicity. For severe infections (including sepsis), doses as high as 12 mg/kg/day have been advocated, but should be used with caution.
小型哺乳類
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Susceptible infections (Llamas) | 4 mg/kg IV q24h; 0.75 mg/kg IV q8h | IV | q8h or q24h | — | 🌎 NA |
- Susceptible infections (Llamas): Dosing specifically for Llamas.
鳥
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Susceptible infections | 5 mg/kg | IM | q12h | — | 🌎 NA |
| Susceptible infections | 2.5-5 mg/kg/day | Parenteral | Daily | — | 🌎 NA |
爬虫類
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Susceptible infections | 2.5 mg/kg | IM | q24h | — | 🌎 NA |
馬
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Susceptible infections | 4 mg/kg | IV | q24h | — | 🌎 NA |
- Susceptible infections: Allows achievement of Cmax/MIC ratio higher than 10 for pathogen strains with a MIC of 1 microgram/mL.
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
トブラマイシンは、主に重篤なグラム陰性好気性細菌感染症に対して優れた有効性を示す、強力な非経口アミノグリコシド系抗生物質です。
主な臨床的特徴：
- 抗菌スペクトル： 好気性グラム陰性桿菌（緑膿菌、大腸菌、クレブシエラ、プロテウスなど）および一部の好気性グラム陽性菌（ブドウ球菌など）に対して高い有効性を示します。嫌気性菌および真菌には無効です。
- 臨床的有用性： 固有の毒性があるため、全身投与は通常、他の毒性の低い抗菌薬が無効な重篤で生命を脅かす感染症、または既知のゲンタマイシン耐性株の治療に限定されます。
- 毒性プロファイル： 全てのアミノグリコシド系と同様に、腎毒性および耳毒性の重大なリスクを伴います。一部の実験室データではゲンタマイシンより腎毒性がわずかに低い可能性が示唆されていますが、臨床的には依然として議論の余地があります。
臨床のポイント： アミノグリコシド系は濃度依存性の殺菌作用と有意なポストアンチビオティックエフェクト（PAE）を示します。このPK/PDプロファイルは、現代の高用量・投与間隔延長（1日1回）投与法を強く支持するものです。このアプローチにより、細菌死滅のための$C_{max}$/MIC比を最大化しつつ、腎尿細管細胞が薬物をクリアランスするための休薬期間を設け、腎毒性を最小限に抑えることができます。
作用機序
Tobramycin is a bactericidal antibiotic that disrupts bacterial protein synthesis.
- Cellular Entry: The drug enters the bacterial cell via an oxygen-dependent active transport mechanism.
Note: Because this transport requires oxygen, aminoglycosides are completely ineffective against obligate anaerobic bacteria and have reduced efficacy in anaerobic environments (e.g., abscesses, necrotic tissue).
- Target Binding: Once inside, tobramycin irreversibly binds to the 30S ribosomal subunit.
- Mechanism: Binding → misreading of mRNA → incorporation of incorrect amino acids into the growing peptide chain → production of non-functional or toxic proteins → bacterial cell death.
- Environmental Factors: Antimicrobial activity is significantly enhanced in an alkaline environment and diminished in acidic, purulent conditions.
安全性・警告
禁忌
- Known hypersensitivity to aminoglycosides
- Rabbits and hares (causes fatal disruption of GI flora)
- Pre-existing severe renal disease (unless benefits outweigh risks)
- Dehydration
- Corneal ulceration (specifically for ophthalmic preparations)
有害事象
- Nephrotoxicity (acute tubular necrosis)
- Ototoxicity (vestibular and auditory damage, potentially irreversible)
- Facial edema
- Pain or inflammation at the injection site
- Peripheral neuropathy
- Hypersensitivity reactions
- Rarely: GI signs, hematologic, and hepatic effects
- Neuromuscular blockade (rare)
注意事項
Extreme Caution Required:
- Renal Impairment: Use with extreme caution in patients with preexisting renal disease. Dosage intervals must be extended, and therapeutic drug monitoring is highly recommended.
- Risk Factors: Neonatal and geriatric patients, fever, sepsis, and dehydration significantly increase the risk of toxicity.
- Working Dogs: Use cautiously in working dogs (e.g., seeing-eye, herding, hearing-assistance dogs) due to the risk of irreversible ototoxicity (deafness or vestibular dysfunction).
- Neuromuscular Disorders: Avoid or use with extreme caution in patients with myasthenia gravis or other neuromuscular disorders due to the drug's neuromuscular blocking activity.
- Feline Sensitivity: Cats appear to be particularly sensitive to the vestibular toxic effects of aminoglycosides.
医薬品相互作用
Synergistic antibacterial effects in vivo; however, can cause physical inactivation of aminoglycosides if mixed in the same syringe or IV line, or in vivo in patients with severe renal failure.
Potential for additive nephrotoxicity (historically documented with older generation cephalosporins like cephalothin).
Increased risk of nephrotoxicity and ototoxicity.
Increased risk of nephrotoxicity and ototoxicity.
Significantly increased risk of acute kidney injury.
Concomitant use can potentiate and prolong neuromuscular blockade, potentially leading to respiratory paralysis.
Increased risk of nephrotoxicity
Increased risk of ototoxicity and nephrotoxicity
In vitro chemical inactivation if mixed
Enhanced non-depolarizing neuromuscular blockade
監視
- Clinical efficacy (resolution of fever, improved clinical signs, negative follow-up cultures)
- Renal toxicity: Baseline and serial urinalysis (monitoring for tubular casts, which are often the first sign of impending toxicity), urine specific gravity, serum creatinine, and BUN
- Gross monitoring for vestibular toxicity (head tilt, nystagmus, ataxia) or auditory toxicity (deafness)
- Therapeutic drug monitoring (peak and trough serum levels) is highly recommended to ensure efficacy and prevent toxicity
- Urinalysis (daily, looking for cellular casts as an early warning)
- Serum creatinine and BUN (baseline and periodically)
- Hydration status and urine output
- Auditory and vestibular function
薬物動態
半減期
吸収
Not appreciably absorbed after oral or intrauterine administration. Absorbed from topical administration during surgical irrigations. Bioavailability from extravascular injection (IM or SC) is >90%. SC injection results in slightly delayed peak levels compared to IM.
分布
Distributed primarily in the extracellular fluid. Found in ascitic, pleural, pericardial, peritoneal, synovial, and abscess fluids. High levels in sputum, bronchial secretions, and bile. Minimally protein bound (<20%). Does not readily cross the blood-brain barrier or penetrate ocular tissue. Crosses the placenta (fetal concentrations 15-50% of maternal serum). Accumulates in inner ear and kidneys. Volume of distribution (horses): 0.24-0.55 L/kg.
代謝
Aminoglycosides are not significantly metabolized.
消失
Eliminated almost entirely by glomerular filtration. Clearance (horses): 101-130 mL/kg/hr. Patients with decreased renal function can have significantly prolonged half-lives.
過剰投与
In the event of an inadvertent overdose, rapid intervention is required to prevent permanent renal and otic damage:
- Hemodialysis: Highly effective in reducing serum levels of the drug, though rarely available in veterinary practice.
- Peritoneal Dialysis: Can reduce serum levels but is significantly less efficacious than hemodialysis.
- Drug Complexation: Intravenous administration of carbenicillin or ticarcillin (12-20 grams/day in humans) can complex with tobramycin in the blood, inactivating it. This is reportedly nearly as effective as hemodialysis.
製品
製剤
- Injection solution
- Powder for injection
- Inhalation solution
- Ophthalmic preparations
- Injectable: 40 mg/ml solution
動物用医薬品
- Tobramycin 40 mg/ml injectable solution
ヒト用医薬品
- Tobramycin Sulfate Injection: 0.8 mg/mL and 1.2 mg/mL in single-dose containers
- Tobramycin Sulfate Solution for Injection: 10 mg/mL and 40 mg/mL
- Tobramycin Sulfate Powder for Injection: 1.2 grams (40 mg/mL after reconstitution)
- Tobramycin Solution for inhalation: 60 mg/mL (TOBI)
- Nebcin 40 mg/ml injectable solution
規制ステータス
POM (Prescription Only Medicine)
POM-V
規制データなし: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
保管・安定性
Store at room temperature (15-30°C); avoid freezing and temperatures above 40°C. Do not use the product if discolored.
飼主向け情報
トブラマイシンは重篤な感染症のために予約されている強力な抗生物質です。その強力な作用のため、ペットの安全を確保するための慎重なモニタリングが必要です。
- 投与方法： 自宅で皮下注射を行うよう指示された場合は、正確な技術と投与スケジュールを完全に理解していることを確認してください。処方された量を超えて投与しないでください。
- 潜在的なリスク： この薬には腎臓の損傷や聴覚または平衡感覚の問題（耳毒性）を引き起こすリスクがあります。
- 注意すべき症状： 以下のいずれかに気づいた場合は、直ちに獣医師に連絡してください：
- 排尿の変化（水を多く飲む、尿量が増える、または減る）
- バランスの喪失、つまずき、頭の傾き、または異常な眼球運動
- 明らかな難聴または音に対する無反応
- 無気力、嘔吐、または食欲不振
- フォローアップ： 血液検査および尿検査の予約は必ず守ってください。これらの検査は、永久的な損傷が起こる前に腎臓への負担の初期兆候を捉えるために非常に重要です。
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。