青黴素V鉀 (盤尼西林V鉀)
Penicillin V Potassium
Phenoxymethylpenicillin potassium
別名: Veetids · fenoximetilpenicilina · penicillin phenoxymethyl · phenomycilline · phenoxymethylpenicillinum
由 VetSheet 獸醫團隊審訂更新於 2026年4月5日本內容以實證獸醫文獻為本
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各物種劑量
🌎 NA — North America🌍 EU — Europe
狗
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Susceptible infections | 5.5-11 mg/kg | PO | q6-8h | — | 🌎 NA |
| Soft tissue infections | 10 mg/kg | PO | q8h | 7 days | 🌎 NA |
貓
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Susceptible infections | 5.5-11 mg/kg | PO | q6-8h | — | 🌎 NA |
| Soft tissue infections | 10 mg/kg | PO | q8h | 7 days | 🌎 NA |
馬
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Susceptible infections | 110,000 U/kg (68.75 mg/kg) | PO | q8h | — | 🌎 NA |
| Susceptible infections | 110,000 U/kg | PO | q6-12h | — | 🌎 NA |
- Susceptible infections: May yield supra-optimal levels against uncomplicated infections by sensitive organisms
劑量為持牌獸醫專業人員的臨床參考。請務必對照最新藥品說明書及個別病患確認。
概覽
青黴素V鉀是一種天然的窄效β-內醯胺類抗生素。與青黴素G相比，它對胃酸的抵抗力更強，因此在單胃動物中口服吸收更好，常用於治療輕至中度的敏感性細菌感染。
作用機制
Penicillin V is a time-dependent, bactericidal antibiotic.
It works by targeting the bacterial cell wall:
- Binds to specific penicillin-binding proteins (PBPs) (such as transpeptidases and carboxypeptidases) located inside the bacterial cytoplasmic membrane.
- Inhibits the third and final stage of bacterial cell wall synthesis by preventing the cross-linking of peptidoglycan strands.
- This leads to a defective, osmotically unstable cell wall (spheroplast) → cell lysis and death.
Note: Like all beta-lactams, it is only effective against actively growing and dividing bacteria.
安全性與警告
禁忌症
- Known hypersensitivity to penicillins
- Oral administration in patients with septicemia, shock, or grave illness (due to delayed/diminished GI absorption)
- Use in sensitive species (snakes, birds, turtles, guinea pigs, chinchillas) without extreme caution
不良反應
- GI effects (anorexia, vomiting, diarrhea)
- Hypersensitivity reactions (rashes, fever, eosinophilia, anaphylaxis)
- Antibiotic-associated diarrhea and superinfections (due to altered gut flora)
- Neurotoxicity (e.g., ataxia in dogs) at very high doses
- Elevated liver enzymes
- Tachypnea, dyspnea, edema, and tachycardia (reported in dogs)
注意事項
Use with caution in patients with documented hypersensitivity to other beta-lactam antibiotics (e.g., cephalosporins, carbapenems) due to potential cross-reactivity. High doses of potassium salts can cause electrolyte imbalances, particularly in small animals with preexisting renal disease, congestive heart failure, or electrolyte abnormalities. Safe use during pregnancy is not firmly established (FDA Category B), and it is excreted in maternal milk, which could cause diarrhea or candidiasis in nursing offspring.
藥物相互作用
In vitro synergism against certain bacteria; however, mixing them in the same syringe or fluid line can cause physical inactivation of the aminoglycoside.
May antagonize the bactericidal activity of penicillins, which require actively dividing bacteria to be effective.
Penicillins may decrease the renal elimination of methotrexate, potentially increasing its toxicity.
Competitively blocks the renal tubular secretion of penicillins, significantly increasing their serum levels and half-lives.
監測
- Clinical efficacy (resolution of infection signs)
- Adverse GI effects
- Signs of hypersensitivity or allergic reaction
藥物動力學
半衰期
吸收
Significantly more resistant to acid-catalyzed inactivation in the gut compared to Penicillin G. Oral bioavailability is 60-73% in humans, but only 30% in calves. In dogs, food decreases the rate and extent of absorption.
分佈
Distributes widely into tissues. Bound to plasma proteins to a larger extent than Penicillin G (approximately 80%). Crosses the placenta and is excreted in maternal milk.
代謝
Minimal hepatic metabolism.
排除
Excreted rapidly in the urine via the kidneys (tubular secretion and glomerular filtration).
過量
Acute oral overdoses are unlikely to cause significant problems other than gastrointestinal distress (vomiting, diarrhea). In humans, massive overdoses of parenteral penicillins (especially in patients with renal impairment) have induced CNS effects and seizures. Treatment is supportive.
可用產品
劑型
- Tablets
- Powder for oral solution
人用標示
- Penicillin V Potassium Tablets: 250 mg & 500 mg (Veetids, generic)
- Penicillin V Potassium Powder for Oral Solution: 25 mg/mL & 50 mg/mL in 100 mL & 200 mL (Veetids, generic)
各地核准狀態
暫無法規資料: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Tablets and powder for oral solution should be stored in tight containers at room temperature (15-30°C). After reconstitution, the oral solution must be stored in the refrigerator (2-8°C) and any unused portion discarded after 14 days.
飼主須知
請在空腹時（飯前1小時或飯後2小時）給予此藥物。如果是口服懸浮液，請冷藏保存，並在14天後丟棄未用完的部分。若寵物出現嚴重腹瀉或過敏反應，請立即聯繫獸醫。
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