메트로니다졸
Metronidazole
2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethanol; Metronidazole benzoate
다른 이름: Flagyl · Metrobactin · Stomorgyl · Metronidazole benzoate · Bayer-5360 · metronidazolum · SC-32642 · NSC-50364 · RP-8823 · SC-10295
VetSheet 수의사 팀 검수업데이트 2026년 4월 5일근거 기반 수의학 참고자료
감사 완료 v13 용량 근거
구조화 용량 계산 근거Anaerobic infections (extra-label) — less severe anaerobic infections
- q8-12h
NA
반드시 함께 고려할 임상 맥락 (6)
- 1. Dosages are for metronidazole base unless otherwise noted. If metronidazole benzoate is being used, dosages should be adjusted unless provided by pharmacy as “mg/mL of the base.”
- One mg of metronidazole base = 1.6 mg of metronidazole benzoate. For example, if the calculated metronidazole dose is 200 mg (of the base), the corresponding dose using metronidazole benzoate would be 320 mg (metronidazole benzoate).
- 2. Because of the drug’s extreme bitterness, using a flavored, compounded metronidazole benzoate or putting quartered tablets in an empty gelatin capsule may be considered.
- Anaerobic infections (extra-label):
- ■ Give this medication with food.
- Metronidazole tablets and solution for injection should be stored at temperatures less than 30°C (86°F) and protected from light. The shelf life of divided tablets is 3 days. 5
Hepatic encephalopathy (extra-label)
- q8-12h
NA
반드시 함께 고려할 임상 맥락 (5)
- 1. Dosages are for metronidazole base unless otherwise noted. If metronidazole benzoate is being used, dosages should be adjusted unless provided by pharmacy as “mg/mL of the base.”
- One mg of metronidazole base = 1.6 mg of metronidazole benzoate. For example, if the calculated metronidazole dose is 200 mg (of the base), the corresponding dose using metronidazole benzoate would be 320 mg (metronidazole benzoate).
- 2. Because of the drug’s extreme bitterness, using a flavored, compounded metronidazole benzoate or putting quartered tablets in an empty gelatin capsule may be considered.
- ■ Give this medication with food.
- Metronidazole tablets and solution for injection should be stored at temperatures less than 30°C (86°F) and protected from light. The shelf life of divided tablets is 3 days. 5
용량은 수의사 전문가를 위한 임상 참고자료입니다. 반드시 최신 약물 정보 및 개별 환자에 따라 확인하시기 바랍니다.
개요
메트로니다졸은 수의학에서 널리 사용되는 합성 니트로이미다졸계 항균 및 항원충제입니다.
주요 임상 적용:
- 항원충: 지알디아(Giardia), 트리코모나스(Trichomonas), 이질아메바(Entamoeba histolytica), 대장섬모충(Balantidium coli)에 매우 효과적입니다.
- 항혐기성균: 절대 혐기성균(예: 박테로이데스, 클로스트리디움, 푸소박테리움)에 대해 우수한 효능을 보입니다. 패혈증, 복막염, 깊은 교상 등을 포함한 장내 및 전신 혐기성 감염 치료에 자주 사용됩니다.
- 위장관 조절: 염증성 장질환(IBD) 및 만성 대장염 관리에 자주 활용됩니다. 임상 팁: 항균 특성 외에도 메트로니다졸은 세포 매개 면역을 억제함으로써 위장관에서 국소적인 면역 조절 및 항염증 효과를 갖는 것으로 여겨집니다.
중요 고려사항:
- FDA에 의해 식용 동물에 대한 사용이 엄격히 금지되어 있습니다.
- 매우 쓴 금속성 맛으로 악명이 높으며, 특히 고양이에서 심한 침흘림과 투약 거부를 유발할 수 있습니다. 고양이 환자의 경우 타액에 덜 녹아 쓴맛이 덜한 조제용 메트로니다졸 벤조에이트가 종종 선호됩니다.
작용 기전
Metronidazole is a concentration-dependent bactericidal agent.
Mechanism Pathway:
- Entry: The drug enters the cell of the organism via passive diffusion.
- Activation: In obligate anaerobes and certain protozoa, the nitro group of metronidazole is reduced by electron-transport proteins (such as ferredoxin).
- DNA Disruption: This reduction process creates highly reactive, short-lived cytotoxic intermediate compounds (free radicals) → These radicals bind to and disrupt DNA and nucleic acid synthesis → leading to rapid cell death.
Because aerobic bacteria lack the specific electron-transport proteins required to reduce and activate the drug, metronidazole is virtually inactive against obligate aerobes.
안전성·주의사항
금기사항
- Hypersensitivity to metronidazole or other nitroimidazole derivatives
- Food-producing animals (FDA prohibited)
- Pregnancy (potential teratogen, especially in early pregnancy)
- Severe hepatic disease (requires dose reduction)
부작용
- Neurologic disorders (ataxia, nystagmus, seizures, head-tilt)
- Lethargy and weakness
- Neutropenia
- Hepatotoxicity
- Hematuria
- Anorexia, nausea, vomiting, and diarrhea
- Hypersalivation (especially in cats due to bitter taste)
- CNS toxicity (nystagmus, ataxia, knuckling, head tilt, seizures)
- Haematuria
- Excessive salivation/foaming (especially in cats)
- Impaired sense of smell (reported in explosive detection dogs)
주의
Neurotoxicity Warning: In dogs, total daily doses should not exceed 65 mg/kg/day to minimize the risk of central vestibular and cerebellar toxicity. Toxicity can occur with acute high doses or chronic moderate-to-high dose therapy.
- Hepatic Impairment: Use with caution in animals with hepatic dysfunction. Consider reducing the dose to 25-50% of the usual dose in significant liver impairment.
- Pregnancy: Potential teratogen. Avoid use during pregnancy, particularly during the first 3 weeks of gestation, unless benefits clearly outweigh risks.
- Nursing: Consider alternative therapy or switching to milk replacer due to potential tumorigenicity.
- Debilitated Patients: Use with extreme caution in severely debilitated animals.
약물 상호작용
May induce a disulfiram-like reaction (nausea, vomiting, cramps).
May decrease the metabolism of metronidazole, increasing the likelihood of dose-related side effects.
May increase the metabolism of metronidazole, thereby decreasing blood levels.
May increase the metabolism of metronidazole, thereby decreasing blood levels.
May prolong the prothrombin time (PT). Avoid concurrent use or intensify monitoring.
Should not be used concurrently with Spiramycin (in combination products) as the combination may be antagonistic.
모니터링
- Clinical efficacy (resolution of diarrhea, negative fecal tests)
- Adverse effects (especially neurologic signs like ataxia or nystagmus)
- Neurological signs (for early detection of CNS toxicity)
- Liver function tests (ALT, AST, Bilirubin) in patients with pre-existing hepatic disease
- Complete Blood Count (for neutropenia)
약동학
반감기
흡수
Relatively well absorbed after oral administration. Oral bioavailability in dogs is high (50-100%) and enhanced with food. In cats, bioavailability averages ~65%. In horses, oral bioavailability averages ~80% (decreased by 50% if given rectally).
분포
Highly lipophilic and widely distributed to most body tissues and fluids, including bone, abscesses, the CNS, and seminal fluid. Less than 20% bound to plasma proteins.
대사
Primarily metabolized in the liver via several pathways, including glucuronidation.
배설
Both metabolites and unchanged drug are eliminated in the urine and feces.
과다투여
Signs of intoxication in dogs and cats are primarily neurologic and include:
- Anorexia and/or vomiting
- Depression
- Mydriasis (dilated pupils)
- Nystagmus (rapid eye flicking, very common in dogs)
- Ataxia (stumbling, uncoordinated gait)
- Head-tilt, proprioceptive deficits, joint knuckling
- Tremors, seizures, rigidity, and stiffness
These effects may be seen with acute massive overdoses, or more commonly with chronic therapy at doses >60 mg/kg/day (though sometimes seen at 'recommended' doses like 30 mg/kg/day).
Treatment:
- Discontinue metronidazole immediately. Most dogs with mild to moderate signs improve rapidly within 1-2 days of stopping the drug.
- Diazepam has been used successfully to rapidly decrease the CNS effects associated with metronidazole toxicity.
- For acute massive ingestions, standard decontamination protocols (emesis, activated charcoal) apply, but use extreme caution before inducing vomiting if the patient is already showing CNS signs, due to aspiration risk.
제품
제형
- Oral capsules
- Extended-release oral tablets
- Injection (IV)
- Compounded oral suspensions (often using metronidazole benzoate)
- 5 mg/ml i.v. infusion
- 250 mg tablet
- 500 mg tablet
- 25 mg metronidazole + 46.9 mg spiramycin tablet (Stomorgyl 2)
- 125 mg metronidazole + 234.4 mg spiramycin tablet (Stomorgyl 10)
- 250 mg metronidazole + 469 mg spiramycin tablet (Stomorgyl 20)
- 40 mg/ml oral solution
동물용의약품
- None (Prohibited for use in food animals by the FDA)
- Metrobactin 250 mg, 500 mg tablets
- Stomorgyl 2, 10, 20 tablets (combination with spiramycin)
인용의약품
- Metronidazole Oral Tablets: 250 mg & 500 mg (Flagyl, generic)
- Metronidazole Oral Capsules: 375 mg (Flagyl 375, generic)
- Metronidazole Extended-Release Oral Tablets: 750 mg (Flagyl ER)
- Metronidazole Injection: 5 mg/mL in 100 mL vials
- Bismuth Subsalicylate, Metronidazole & Tetracycline HCl Combination (Helidac)
- Flagyl 200 mg, 400 mg tablets
- Metronidazole 5 mg/ml IV infusion
규제 현황
POM-V classification. Prohibited for use in food-producing animals.
POM-V classification.
규제 데이터 없음: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
보관·안정성
Tablets and HCl powder for injection should be stored at temperatures less than 30°C and protected from light. The injection should be protected from light and freezing and stored at room temperature. Compounded metronidazole benzoate suspensions can be stable for up to 90 days or longer depending on the specific vehicle used.
보호자 정보
반려동물 보호자를 위한 중요 안내:
- 매우 쓴 맛: 메트로니다졸 알약은 동물에게 매우 끔찍한 맛이 납니다. 절대적으로 필요한 경우가 아니라면 알약을 부수지 마십시오. 쓴맛으로 인해 반려동물(특히 고양이)이 침을 심하게 흘리거나 음식을 거부할 수 있습니다. 약을 먹이는 데 어려움이 있다면, 쓴맛을 훨씬 잘 숨겨주는 조제용 액상 약(메트로니다졸 벤조에이트)에 대해 수의사에게 문의하십시오.
- 음식과 함께 투여: 이 약을 식사와 함께 먹이면 흡수율을 높이고 위장 장애를 줄이는 데 도움이 될 수 있습니다.
- 신경계 증상 관찰: 반려동물에게 신경 독성 징후가 나타나면 즉시 수의사에게 연락하십시오. 비틀거리거나 "술 취한" 듯한 걸음걸이(운동 실조), 눈동자가 빠르게 좌우로 흔들림(안구 진탕), 고개 기울어짐, 극도의 무기력, 떨림 또는 발작이 있는지 관찰하십시오.
- 처방된 기간을 끝까지 채울 것: 반려동물의 설사나 증상이 호전되더라도, 감염이나 기생충이 완전히 제거될 수 있도록 처방된 약을 끝까지 모두 먹이십시오.
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