莨菪鹼
Hyoscyamine
Hyoscyamine sulfate
別名: Anaspaz · ED-SPAZ · HyoMax · Cystospaz · Neosol · NuLev · Symax · Levbid · Levsinex · IB-Stat · Egazil Duretter · Neo-Allospasmin · daturin · duboisine · tropine-L-tropate
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
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。
各物種劑量
🌎 NA — North America🌍 EU — Europe
狗
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Irritable bowel syndrome | 0.003-0.006 mg/kg PO two to three times a day | PO | q8-12h | — | 🌎 NA |
| Long-term management of symptomatic patients with sinus node disease | 0.003-0.006 mg/kg PO q8h | PO | q8h | Long-term | 🌎 NA |
- Irritable bowel syndrome: Assumed to be for immediate release oral dosage forms.
- Long-term management of symptomatic patients with sinus node disease: Assumed to be for immediate release oral dosage forms.
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
莨菪鹼（Hyoscyamine）是一種顛茄生物鹼，為外消旋阿托品（atropine）的高活性左旋異構物。由於它是具活性的對映異構體，其中樞與周邊的抗膽鹼作用明顯強於阿托品。
在獸醫學中，其應用相對有限，但可作為其他抗膽鹼藥物（如格隆溴銨或阿托品）的有效替代品。主要用於：
- 胃腸道蠕動過速： 透過減少痙攣來控制大腸激躁症（IBS）等疾病。
- 心血管支持： 治療有症狀的心搏過緩或竇房結疾病。
- 圍手術期使用： 潛在可用於減少唾液分泌過多、尿道痙攣及呼吸道分泌物，儘管動物的臨床數據較少。
臨床要點： 由於莨菪鹼比格隆溴銨等四級抗膽鹼藥物更容易穿透血腦屏障，應密切監測病患是否出現中樞神經系統（CNS）副作用，如矛盾性興奮或鎮靜。
作用機制
Hyoscyamine acts as a competitive, reversible antagonist of acetylcholine at muscarinic receptors (M1-M5) located on smooth muscle, cardiac muscle, and glandular cells.
- Gastrointestinal/Urinary: Blocks parasympathetic stimulation → relaxes smooth muscle → decreases GI and urinary tract motility and spasms.
- Secretions: Inhibits glandular muscarinic receptors → dose-dependent reduction in salivary, bronchial, pharyngeal, and gastric secretions.
- Cardiovascular: Blocks vagal (parasympathetic) tone at the sinoatrial (SA) node → increases heart rate.
- Ocular: Paralyzes the pupillary sphincter muscle → causes mydriasis (pupil dilation).
安全性與警告
禁忌症
- Hypersensitivity to hyoscyamine or other belladonna alkaloids
- Glaucoma (narrow or wide angle)
- Intestinal obstruction or intestinal atony
- Toxic megacolon
- Severe ulcerative colitis
- Obstructive uropathy
- Acute hemorrhage with cardiovascular instability
不良反應
- Mydriasis (pupil dilation)
- Xerostomia (dry mouth)
- Constipation
- Urinary retention
- Xerophthalmia (dry eyes)
- Tachycardia
- CNS effects (somnolence, delirium, or paradoxical excitement at higher doses)
注意事項
Use with extreme caution in patients with renal dysfunction, as drug elimination may be reduced. Carefully consider the risks before using in patients with tachyarrhythmias, cardiac valve disease, or congestive heart failure due to its chronotropic effects. May aggravate myasthenia gravis. FDA Pregnancy Category C; use during pregnancy only if clearly needed. It is excreted in trace amounts in milk; while likely safe, risk to nursing offspring cannot be entirely ruled out.
藥物相互作用
May interfere with the gastrointestinal absorption of hyoscyamine.
Additive anticholinergic actions and increased risk of adverse effects.
Additive anticholinergic actions and increased risk of adverse effects.
Hyoscyamine may antagonize and counteract their gastrointestinal prokinetic effects.
監測
- Clinical efficacy (resolution of GI spasms or improvement in heart rate)
- Heart rate and rhythm
- Bowel elimination (monitor for constipation/ileus)
- Urinary elimination (monitor for urinary retention)
藥物動力學
吸收
Rapidly and nearly completely absorbed after oral or sublingual administration. Extended-release oral dosage forms may have somewhat reduced oral bioavailability.
分佈
Distributed widely throughout the body. Readily enters the central nervous system (CNS) and crosses the placenta.
代謝
Partially hydrolyzed in the liver to tropic acid and tropine.
排除
The majority of the drug is excreted unchanged in the urine.
過量
Significant overdosage can be life-threatening; contacting an animal poison control center is strongly advised. The LD50 in rats is 375 mg/kg.
Clinical Signs of Toxicity:
- Intensified anticholinergic effects: severe tachycardia, mydriasis, urinary retention, and absent gut sounds (ileus).
- CNS signs: behavioral changes, severe depression, delirium, or seizures.
Treatment:
- Decontamination: Protocols to decrease oral absorption (e.g., emesis, activated charcoal) should be considered if the overdose was recent and the patient is asymptomatic.
- Antidote: Severe anticholinergic effects can be treated with physostigmine or neostigmine, but this should only be done under the strict guidance of a poison control center due to the risk of cholinergic crisis.
- Supportive Care: Delirium or excitement can be managed with small doses of short-acting barbiturates or benzodiazepines. Hyoscyamine can be removed by hemodialysis.
可用產品
劑型
- Oral tablets (immediate, chewable, orally disintegrating, sublingual)
- Extended-release tablets and capsules
- Oral solution and elixir
- Oral spray
- Injection (solution)
人用標示
- Hyoscyamine Oral Tablets: 0.125 mg (regular & chewable), 0.15 mg
- Hyoscyamine Orally Disintegrating Tablets: 0.125 mg, 0.25 mg
- Hyoscyamine Sublingual Oral Tablets: 0.125 mg
- Hyoscyamine Extended/Sustained-Release Oral Tablets: 0.25 mg, 0.375 mg
- Hyoscyamine Extended/Timed-Release Oral Capsules: 0.375 mg
- Hyoscyamine Oral Solution: 0.125 mg/mL
- Hyoscyamine Oral Elixir: 0.025 mg/mL
- Hyoscyamine Oral Spray: 0.125 mg/spray
- Hyoscyamine Injection: 0.05 mg/mL
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
Unless otherwise advised by the manufacturer, oral products should be stored at room temperature in tight containers and protected from light. Injectable products should be stored at room temperature and protected from freezing.
飼主須知
莨菪鹼用於緩解胃腸道痙攣或幫助提高過慢的心跳速率。
- 充足飲水： 此藥物經常會導致口乾。請確保您的寵物隨時有充足的新鮮飲水。
- 監測排泄： 密切觀察寵物的排泄習慣。如果您的寵物排尿困難、無法排尿或出現便秘，請立即聯繫您的獸醫師。
- 其他副作用： 如果您發現寵物有眼睛乾澀、吞嚥困難或行為出現異常改變（如極度嗜睡、焦躁不安或激動），請聯繫獸醫師。
- 忘記服藥： 如果忘記服藥，請在想起時盡快補服。但如果已經接近下一次服藥時間，請跳過漏服的劑量，切勿一次給予雙倍劑量。
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