硝唑尼特
Nitazoxanide
Nitrothiazolyl-salicylamide derivative
別名: Alinia · Navigator · Daxon · Heliton · PH-5776 · desacetyl-nitazoxanide (active metabolite tizoxanide)
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
經審核的 v13 劑量證據
結構化劑量計算證據Giardia spp associated diarrhea (extra-label)
須由已驗證獸醫確認
- once
NA
必須同時考慮的臨床上下文 (1)
- The human-approved powder for oral suspension should be stored at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F-86°F). Once suspended with tap water, the oral suspension should be kept in tightly closed containers at room temperature and discarded after 7 days.
Cryptosporidia spp associated diarrhea (extra-label)
須由已驗證獸醫確認
- once
NA
必須同時考慮的臨床上下文 (1)
- The human-approved powder for oral suspension should be stored at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F-86°F). Once suspended with tap water, the oral suspension should be kept in tightly closed containers at room temperature and discarded after 7 days.
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
硝唑尼特 (Nitazoxanide) 是一種廣效的噻唑類抗寄生蟲與抗菌藥物。
臨床重點：
- 廣效性：對多種原蟲（包括肉孢子蟲、梨形鞭毛蟲、隱孢子蟲）、線蟲、吸蟲及厭氧菌（如幽門螺旋桿菌）具有活性。
- 馬匹用途：過去曾獲 FDA 批准作為口服糊劑 (Navigator®) 用於治療馬原蟲性脊髓腦炎 (EPM)，但該產品已退出美國市場。
- 小動物用途：臨床上對於犬貓難治性隱孢子蟲和梨形鞭毛蟲感染的標示外使用有相當大的興趣。然而，其在小動物的臨床應用常因明顯的胃腸道副作用（尤其是犬隻）而受限。
- 人類用途：獲 FDA 批准用於治療人類由微小隱孢子蟲和梨形鞭毛蟲引起的腹瀉，且耐受性通常非常良好。
作用機制
Nitazoxanide acts as a prodrug and is rapidly converted into its active metabolites, tizoxanide and tizoxanide glucuronide.
- Mechanism: It inhibits the pyruvate:ferredoxin oxidoreductase (PFOR) enzyme-dependent electron transfer reactions.
- Pathway: Inhibition of PFOR → disruption of essential anaerobic energy metabolism → death of susceptible protozoa and anaerobic bacteria.
- Unlike nitroimidazoles (e.g., metronidazole), nitazoxanide does not appear to cause DNA damage, reducing its mutagenic potential.
安全性與警告
禁忌症
- Horses less than 1 year of age
- Horses that are sick or debilitated for reasons other than EPM
- Use with extreme caution in stallions and horses predisposed to laminitis
- Animals with compromised renal or hepatic function (safety not established)
不良反應
- Horses: Fever, anorexia, lethargy/depression, decreased gut sounds, diarrhea/enterocolitis, colic, laminitis, head/limb edema
- Horses: 'Treatment crisis' (CNS inflammation secondary to dying protozoa)
- Dogs: Excessive salivation, vomiting, diarrhea (often therapy-limiting)
- Humans: Yellow discoloration of sclera (rare, reversible)
注意事項
Use with caution in animals with compromised renal or hepatic function. In horses, monitor closely for signs of enterocolitis (disruption of normal flora) and laminitis (stallions may be more prone). A 'treatment crisis' may occur in horses during the first two weeks of EPM therapy due to CNS inflammation from dying protozoa, which may require anti-inflammatory therapy. Not evaluated in horses weighing > 1200 lbs.
藥物相互作用
Use with caution; tizoxanide is >99% protein bound and may displace or be displaced by other highly bound drugs, potentially altering free drug concentrations.
監測
- Clinical efficacy (resolution of diarrhea or neurological signs)
- Weekly body weight
- Adverse reactions (GI upset, hypersalivation)
- If adverse reactions occur: Physical exam, CBC, serum albumin, total serum protein
藥物動力學
半衰期
吸收
Absorbed orally and rapidly converted to the active metabolite tizoxanide (desacetyl-nitazoxanide).
分佈
More than 99% of tizoxanide is bound to plasma proteins.
代謝
Rapidly hydrolyzed to tizoxanide, which is further conjugated to tizoxanide glucuronide.
排除
Tizoxanide is excreted in the urine, bile, and feces; the glucuronide metabolite is secreted in the urine and bile.
過量
Information on acute toxicity is limited.
- Horses: Overdoses of 2.5X have been associated with fatalities. Doses of ~5X labeled dose caused anorexia, diarrhea, and lethargy within 4 days.
- Dogs/Cats: Oral LD50 is > 10 g/kg.
- Rats: Repeated doses of 450 mg/kg caused intense salivation and increased liver/spleen weights.
- Humans: Doses up to 4 grams have been taken without significant adverse effects.
Treatment: In the event of an overdose, observe the patient closely and provide supportive care.
可用產品
劑型
- Oral Tablets
- Powder for Oral Suspension
- Oral Paste (Veterinary - Withdrawn)
獸醫用
- Nitazoxanide oral paste (32%); Navigator® (FDA approval withdrawn; no longer marketed)
人用標示
- Nitazoxanide Oral Tablets: 500 mg; Alinia®
- Nitazoxanide Powder for Oral Suspension: 20 mg/mL (100 mg/5 mL after reconstitution); Alinia®
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
Store the human-approved powder for oral suspension at 25°C (77°F); excursions permitted to 15-30°C (59-86°F). Once reconstituted with tap water, keep the oral suspension in tightly closed containers at room temperature and discard after 7 days.
飼主須知
寵物主人重要須知：硝唑尼特在犬貓中並不常用，在獸醫學上屬於「標示外使用」(off-label use)。
- 副作用：在犬貓中，此藥物可能會引起明顯的腸胃不適，包括過度流口水、嘔吐和腹瀉。如果出現這些症狀，請聯繫您的獸醫師，可能需要停藥。
- 給藥方式：請嚴格遵循獸醫師的給藥指示。未經諮詢請勿自行調整劑量。
- 監測：在治療期間，請密切注意寵物的食慾、精神活力和體重變化。
VetSheet 藥物參考供持牌獸醫專業人員作臨床決策輔助之用，不能取代專業判斷或廠方最新藥品說明書。