Amikacin
Amikacin is a potent aminoglycoside antibiotic primarily active against severe Gram-negative bacterial infections, *Staphylococcus aureus*, and *Nocardia* spp. It is particularly valuable for treating infections resistant to other aminoglycosides like gentamicin. **Clinical Pearl:** Streptococci and anaerobic bacteria are typically resistant. Activity is significantly reduced in low-oxygen environments (e.g., abscesses, necrotic tissue). > **Warning:** Amikacin has poor penetration across biological membranes; systemic levels require parenteral administration, and it achieves very limited concentrations in the CNS and ocular fluids. It carries significant risks of **nephrotoxicity** and **ototoxicity**.
กลไกการออกฤทธิ์: Aminoglycosides irreversibly bind to the **30S ribosomal subunit** of susceptible bacteria, inhibiting bacterial protein synthesis. They exhibit **concentration-dependent killing** → leading to a marked **post-antibiotic effect** (PAE). This allows for prolonged dosing intervals (e.g., q24h), which maximizes bacterial kill rates while minimizing accumulation in renal tubular cells, thereby reducing toxicity.
ขนาดยาตามชนิดสัตว์
- Susceptible bacterial infections · 15-30 mg/kg · IV/IM/SC · q24h · Not specified · IV doses should be given slowly over 30-60 minutes.
- Susceptible bacterial infections in Greyhounds and sight hounds · 12 mg/kg · IV/IM/SC · q24h · Not specified · Lower dose recommended due to a lower volume of distribution in these breeds.
- Sepsis · Higher than standard doses · IV/IM/SC · q24h · Not specified · Recommended by some authors, but carries an increased risk of adverse effects.
- Local infections (e.g., joints, bladder) · Varies · topical · Varies · Not specified · Considered if the site is easily accessible and if the animal shows signs of systemic nephrotoxicity.
- Susceptible bacterial infections · 10-15 mg/kg · IV/IM/SC · q24h · Not specified · IV doses should be given slowly over 30-60 minutes.
- Sepsis · Higher than standard doses · IV/IM/SC · q24h · Not specified · Recommended by some authors, but carries an increased risk of adverse effects.
- Local infections (e.g., joints, bladder) · Varies · topical · Varies · Not specified · Considered if the site is easily accessible and if the animal shows signs of systemic nephrotoxicity.
ขนาดยาเป็นข้อมูลอ้างอิงทางคลินิกสำหรับสัตวแพทย์ผู้มีใบอนุญาต โปรดตรวจสอบกับฉลากล่าสุดและผู้ป่วยแต่ละรายเสมอ
วิธีการให้ยา
ข้อห้ามใช้
- Animals with pre-existing reduced renal function (unless benefits outweigh risks)
- Dehydrated patients (without concurrent fluid therapy)
อาการไม่พึงประสงค์
- Nephrotoxicity (tubular necrosis)
- Ototoxicity (vestibular and auditory dysfunction)
- Neuromuscular blockade (rare but possible)
อันตรกิริยาระหว่างยา
- Beta-lactam antimicrobials (Penicillins, Cephalosporins) · In vivo synergism against susceptible bacteria; however, they can cause in vitro inactivation of amikacin. Do not mix in the same syringe. · moderate
- Amphotericin B · Increased risk of severe nephrotoxicity. · major
- Furosemide · Increased risk of ototoxicity and nephrotoxicity. · major
- Heparin · In vitro inactivation of amikacin. Do not mix in the same syringe. · moderate
- Neuromuscular blocking agents · Potentiation of neuromuscular blockade. · major
การติดตาม
- Serum amikacin levels (peak for efficacy, trough for toxicity)
- Renal function (BUN, serum creatinine, urinalysis for casts/proteinuria)
- Hydration status
- Auditory and vestibular function (if possible)
การได้รับยาเกินขนาด
Overdosage significantly increases the risk of **acute tubular necrosis (nephrotoxicity)** and **vestibular/auditory damage (ototoxicity)**. Treatment is supportive. Discontinue the drug immediately and initiate aggressive intravenous fluid therapy to promote diuresis and maintain glomerular filtration rate.
ข้อมูลอ้างอิงยาของ VetSheet มีไว้สำหรับสัตวแพทย์ผู้มีใบอนุญาตเพื่อช่วยในการตัดสินใจทางคลินิก ไม่ใช่สิ่งทดแทนการวินิจฉัยของผู้เชี่ยวชาญหรือฉลากล่าสุดของผู้ผลิต