硫酸ゲンタマイシン
Gentamicin Sulfate
Gentamicin sulfate
別名: Gentocin · Garamycin · Amtech Gentamax 100 · Gentafuse · Gentaved · Gentozen · Legacy · Garasol · Garacin · Gen-Gard · Clinagel Vet · Easotic · Otomax · Tiacil · Genticin · gentamicin sulphate · gentamicini sulfas · NSC-82261 · Sch-9724 · Gentamicine · Gentamycin
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Susceptible infections (extra-label)
認証済み獣医師の確認が必要
- q24h
NA
必ず考慮する臨床コンテキスト (3)
- NOTE: Most infectious disease clinicians agree that aminoglycosides should be dosed once a day in most patients (mammals) with uncompromised renal function. This dosing regimen yields higher peak levels with resultant greater bacterial kill, and as aminoglycosides exhibit a postantibiotic effect, surviving susceptible bacteria generally do not replicate as rapidly even when antibiotic concentrations are below MIC. Periods where levels are low may decrease the adaptive resistance (bacteria take up less drug in the presence of continuous exposure) that can occur. Once-daily dosing may also decrease the toxicity of aminoglycosides, as lower urinary concentrations may mean less uptake into renal tubular cells.
- ■ Therapeutic drug monitoring (TDM) when possible in patients with uncompromised renal function; highly recommended for patients with risk factors for nephrotoxicity. Peak and trough levels are determined through samples collected 30 minutes after administration (peak) and immediately before administration of the next dose (trough). Generally, peak levels (≈30 to 60 minutes post IV dose) should be greater than 32 μg/mL and trough levels less than 1 – 2 μg/mL. 34 A clinical laboratory may be able to assist in sample-time determination and dosage amount and frequency adjustment.
- Gentamicin sulfate for injection and the oral solution should be stored at room temperature (15°C-30°C [59°F-86°F]); freezing or temperatures above 40°C (104°F) should be avoided. The soluble powder should be stored from 2°C to 30°C (46°F-86°F). Do not store or offer medicated drinking water in rusty containers or the drug may be destroyed.
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
ゲンタマイシンは、主に重篤なグラム陰性好気性細菌感染症に使用される強力な非経口アミノグリコシド系抗生物質です。
主な薬理学的特徴は以下の通りです：
- 抗菌スペクトル：グラム陰性好気性菌（大腸菌、クレブシエラ、プロテウス、シュードモナス、サルモネラなど）および一部のブドウ球菌に対して優れた効果を示します。嫌気性菌、真菌、ウイルスには無効です。
- 濃度依存性殺菌作用：病原体の最小発育阻止濃度（MIC）に対して高い血清中ピーク濃度を達成することが有効性の鍵となります。
- ポストアンチバイオティックエフェクト（PAE）：薬物濃度がMICを下回った後も細菌の増殖が抑制されるため、現代の1日1回投与の根拠となっています。
- 毒性プロファイル：腎毒性および耳毒性の重大なリスクがあるため、全身投与は通常、毒性の低い代替薬が無効な重篤な感染症に限定されます。
臨床上のポイント：毒性の危険因子には、既存の腎疾患、年齢（新生児および高齢）、発熱、敗血症、脱水が含まれます。猫は前庭（耳毒性）の影響に対して特に敏感です。
作用機序
Gentamicin is a concentration-dependent bactericidal antibiotic.
- Mechanism: It actively transports across the bacterial cell membrane via an oxygen-dependent mechanism → irreversibly binds to the 30S ribosomal subunit → causes misreading of mRNA → inhibits bacterial protein synthesis, leading to cell death.
- Environmental Factors: Antimicrobial activity is significantly enhanced in an alkaline environment and inhibited in acidic, purulent, or necrotic environments.
- Resistance: Because the transport mechanism requires oxygen, anaerobic bacteria are inherently resistant to all aminoglycosides.
安全性・警告
禁忌
- Known hypersensitivity to aminoglycosides
- Use with extreme caution in preexisting renal disease
- Use with caution in working dogs (e.g., seeing-eye, herding, hearing-impaired assistance dogs) due to irreversible ototoxicity
- Use with caution in patients with neuromuscular disorders (e.g., myasthenia gravis)
- Do not use in animals with botulism
- Use with caution in rabbits (adversely affects GI flora)
- Use with caution in neonates, geriatrics, and dehydrated patients
- Perforated tympanum (for aural preparations)
- Concurrent use of other nephrotoxic drugs
- Systemic use exceeding 7 days
- Pregnancy
有害事象
- Nephrotoxicity (tubular necrosis)
- Ototoxicity (auditory and vestibular; cats are highly sensitive to vestibular effects)
- Facial edema
- Pain or inflammation at the injection site
- Peripheral neuropathy
- Hypersensitivity reactions
- Rarely: GI signs, hematologic, and hepatic effects
- Nephrotoxicity (acute tubular necrosis)
- Neuromuscular blockade (rare)
- Delayed epithelial healing of corneal ulcers (ophthalmic use)
- Local irritation
注意事項
Aminoglycosides are eliminated primarily through renal mechanisms; use cautiously with serum monitoring and dosage adjustments in neonatal or geriatric animals. Sighthound dogs have significantly smaller volumes of distribution and may require reduced dosages. IM injections in horses can cause muscle irritation; IV is preferred. Monitor for antibiotic-associated diarrhea/colitis in horses (may promote Beta-2 toxin production by C. perfringens).
医薬品相互作用
Synergistic effects against some bacteria; however, potential for in vitro inactivation of aminoglycosides (do not mix in the same syringe/bag) and in vivo inactivation in patients with renal failure.
Potential additive nephrotoxicity (well documented with older cephalosporins like cephalothin).
Concurrent use may increase the nephrotoxic or ototoxic potential of aminoglycosides.
Increased risk for nephrotoxicity.
Concomitant use could potentiate neuromuscular blockade.
Increased risk of nephrotoxicity and ototoxicity
Increased risk of nephrotoxicity and ototoxicity
In vitro chemical inactivation (do not mix in same syringe)
Enhanced neuromuscular blockade
監視
- Clinical efficacy (resolution of clinical signs, negative cultures)
- Renal toxicity: Baseline and ongoing urinalysis (casts in urine are often the initial sign of impending nephrotoxicity), serum BUN, and creatinine
- Gross monitoring for vestibular (balance) or auditory (hearing) toxicity
- Therapeutic Drug Monitoring (TDM): Serum levels drawn at 1, 2, and 4 hours post-dose. Peak should be >20 mcg/mL; 4-hour trough should be <10 mcg/mL
- Urinalysis (monitor for cellular casts as an early indicator of tubular damage)
- Serum creatinine and BUN
- Hydration status
- Therapeutic Drug Monitoring (TDM): Peak >20 μg/ml, Trough <1 μg/ml
- 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%. Peak levels occur 0.5 to 1 hour after IM administration.
分布
Distributed primarily in extracellular fluid. Accumulates in inner ear and kidneys. Minimal protein binding (<20%). Does not readily cross the blood-brain barrier or penetrate ocular tissue. Vd is 0.15-0.3 L/kg in adult dogs/cats, and 0.26-0.58 L/kg in horses. Crosses the placenta.
代謝
Not significantly metabolized.
消失
Eliminated almost entirely by glomerular filtration. Patients with decreased renal function can have significantly prolonged half-lives.
過剰投与
In the event of an inadvertent overdose, three treatments are recommended:
- Hemodialysis: Very effective in reducing serum levels, but rarely a viable option in veterinary medicine.
- Peritoneal dialysis: Reduces serum levels but is much less effective than hemodialysis.
- Complexation: Administration of ticarcillin (12-20 g/day in humans) is reportedly nearly as effective as hemodialysis in complexing and deactivating the drug.
製品
製剤
- Injection (100 mg/mL, 40 mg/mL, 10 mg/mL, 5 mg/mL, etc.)
- Oral solution (5 mg/mL)
- Soluble powder
- Ophthalmic preparations
- Otic preparations
- Topical preparations
- Injectable solution: 40 mg/ml, 100 mg/ml
- Ophthalmic gel: 0.3% w/w
- Ophthalmic drops: 0.5% w/v
- Aural drops/ointment: Combination products (e.g., with miconazole/hydrocortisone or clotrimazole/betamethasone)
動物用医薬品
- Gentamicin Sulfate Injection: 100 mg/mL (horses, poultry)
- Gentamicin Sulfate Injection: 5 mg/mL (piglets)
- Gentamicin Sulfate Oral Solution: 5 mg/mL (swine)
- Gentamicin Soluble Powder: 333.33 mg/g and 2 g/30 g (swine)
- Ophthalmic, otic, and topical preparations
- Clinagel Vet (Ophthalmic)
- Easotic (Aural combination)
- Genta (100 mg/ml Injectable)
- Otomax (Aural combination)
- Tiacil (Ophthalmic)
ヒト用医薬品
- Gentamicin Sulfate Injection: 40 mg/mL, 10 mg/mL, 0.8 mg/mL, 0.9 mg/mL, 1 mg/mL, 1.2 mg/mL, 1.4 mg/mL, 1.6 mg/mL
- Topical, otic, and ophthalmic preparations
- Genticin (40 mg/ml Injectable)
規制ステータス
POM-V / POM status
POM-V / POM status
規制データなし: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
保管・安定性
Store injection and oral solutions at room temperature (15-30°C); avoid freezing or temperatures above 40°C. Store soluble powder from 2-30°C. Do not store or offer medicated drinking water in rusty containers, as the drug may be destroyed.
飼主向け情報
ゲンタ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。
- 投与方法：自宅で皮下注射を行うよう指示された場合は、獣医療チームから適切な訓練を受けていることを確認してください。
- 毒性のリスク：この薬には、腎臓の損傷（腎毒性）および聴覚・平衡感覚の異常（耳毒性）の重大なリスクがあります。
- 注意すべき症状：ペットの飲水量が増えた、尿の回数が増減した、嘔吐、食欲不振、耳が聞こえない兆候がある、または首の傾き、つまずき、ふらつきなどが見られた場合は、直ちに獣医師に連絡してください。
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