スルファジメトキシン/オルメトプリム
Sulfadimethoxine/Ormetoprim
Sulfadimethoxine and Ormetoprim
別名: Primor · Rofenaid 40 · Romet 30 · NSC-95072 · ormetoprima · ormétoprime · ormetoprimum · Ro-5-9754 · solfadimetossina · solfadimetossipirimidina · sulphadimethoxine · Chemiosalfa · Deltin · Risulpir · Ritarsulfa · Sulfadren · Sulfastop · Sulfathox
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 |
|---|---|---|---|---|---|
| Susceptible infections (skin and soft tissue) | Initially 55 mg/kg (combined drug) PO on the first day of therapy, then 27.5 mg/kg PO once daily for at least 2 days after remission of clinical signs. Not approved for treatment longer than 21 days. | PO | q24h | Up to 21 days | 🌎 NA |
- Susceptible infections (skin and soft tissue): Dose is based on combined drug weight.
鳥
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| Susceptible infections | Medicated premix: 113.5 grams sulfadimethoxine and 68.1 grams ormetoprim per pound in 50 lb bags | PO | Continuous in feed | Varies | 🌎 NA |
- Susceptible infections: FDA-approved for chickens (broilers, replacements), turkeys, ducks, & Chukar partridges. 5-day slaughter withdrawal. Do not feed to chickens over 16 weeks of age, or turkeys/ducks producing eggs for food.
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
これは強化サルファ系抗菌薬であり、感受性ブドウ球菌や大腸菌による犬の皮膚および軟部組織の感染症治療薬としてFDAに承認されています。他のサルファ剤に比べて副作用が少ない可能性があり、1日1回の投与が可能です。注意: 前立腺への移行性が低いため、前立腺感染症には無効です。
作用機序
Sulfadimethoxine/ormetoprim is bactericidal due to the synergistic, sequential inhibition of enzymes in the bacterial folic acid synthesis pathway.
- Sulfadimethoxine (a sulfonamide) acts as a false substrate, competitively inhibiting the conversion of para-aminobenzoic acid (PABA) → dihydrofolic acid (DFA).
- Ormetoprim (a diaminopyrimidine) blocks the subsequent conversion of DFA → tetrahydrofolic acid (THFA) by reversibly inhibiting the enzyme dihydrofolate reductase.
This dual blockade halts bacterial thymidine synthesis, ultimately preventing DNA replication. It has a broad spectrum of activity against many Gram-positive (e.g., Staphylococcus, Streptococcus, Nocardia) and Gram-negative organisms (excluding Pseudomonas aeruginosa), as well as certain protozoa (Pneumocystis, Coccidia, Toxoplasma).
安全性・警告
禁忌
- Hypersensitivity to sulfonamides, thiazides, or sulfonylurea agents
- Severe renal or hepatic impairment
- Marked liver parenchymal damage
- Blood dyscrasias
- Doberman Pinschers (highly susceptible to sulfonamide-induced poly-systemic immune complex disease)
有害事象
- Keratoconjunctivitis sicca (KCS/dry eye) - potentially irreversible
- Acute neutrophilic hepatitis with icterus
- Vomiting
- Anorexia
- Diarrhea
- Fever
- Hemolytic anemia
- Urticaria
- Polyarthritis
- Facial swelling
- Polydipsia and polyuria
- Cholestasis
- Hypersensitivity reactions (Type I anaphylaxis or Type III serum sickness)
- Hypothyroidism (with extended use)
- Crystalluria and hematuria (especially in cats)
- Leukopenias and anemias
注意事項
Use with caution in patients with pre-existing hepatic or thyroid disease, diminished renal function, urinary obstruction, or urolithiasis. Hypersensitivity reactions appear more common in large breed dogs. Potentially teratogenic (cleft palate reported in lab animals with TMP/sulfa); weigh risk versus benefit in pregnant animals.
医薬品相互作用
Specific interactions are not explicitly noted for this combination, but it is expected to share the interaction profile of trimethoprim/sulfa (e.g., potential antagonism with cyclosporine, increased risk of bleeding with anticoagulants).
監視
- Clinical efficacy and resolution of infection
- Adverse effects (especially signs of hypersensitivity or liver issues)
- Tear production via Schirmer Tear Test in dogs (baseline, at 5 days post-initiation, and then every 2-3 weeks)
薬物動態
分布
Ormetoprim does not attain clinically effective levels in the prostate for treating bacterial prostatic infections.
過剰投与
In experimental dog studies, doses >80 mg/kg resulted in slight tremors and increased motor activity. Higher doses may cause depression, anorexia, or seizures.
Treatment: For very high oral overdoses, empty the gut using standard precautions and protocols. Treat clinical signs supportively and symptomatically.
製品
製剤
- Tablets
- Medicated premix
動物用医薬品
- Sulfadimethoxine/Ormetoprim Tablets (scored): 120 mg (100 mg sulfa/20 mg ormetoprim), 240 mg, 600 mg, 1200 mg (Primor)
- Sulfadimethoxine/Ormetoprim medicated premix (Rofenaid 40, Romet 30)
規制ステータス
規制データなし: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
保管・安定性
Unless otherwise instructed by the manufacturer, store tablets in tight, light-resistant containers at room temperature.
飼主向け情報
- 水分の確保：脱水や尿結石を防ぐため、常に新鮮な水を飲めるようにしてください。
- 目の観察：「ドライアイ」の兆候（目を細める、充血、粘り気のある目やに）に注意してください。これらの症状が出た場合は、永久的な目の損傷を防ぐため、すぐに獣医師に連絡してください。
- アレルギー反応：顔の腫れ、じんましん、嘔吐、発熱、関節痛、または極度の無気力が見られた場合は、投薬を中止し、すぐに獣医師に連絡してください。
- 処方通りに正確に投薬し、ペットの症状が良くなったように見えても、耐性菌の発生を防ぐために最後まで薬を飲み切ってください。
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。