咪達唑侖
Midazolam
Midazolam hydrochloride
別名: Versed · Dormicum · Dormonid · Fulsed · Hypnovel · Midaselect · Zolamid · Buccolam · Epistatus · Midazolam HCl · Ro-21-3981/003 · Midazolamum · Midazolam hydrochloride
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
經審核的非計算證據經審核的非計算證據 (1)
只供證據參考，不會自動計算
Preanesthetic agent (extra-label)
Preanesthetic agent (extra-label): 0.5 – 5 mg/kg IM or IV
必須同時考慮的臨床上下文 (2)
- NOTE: There are many potential combinations that have been suggested; the following are examples and not inclusive. For additional information, refer to other anesthesia-specific references. 25
- Store midazolam injection at room temperature (15°C-30°C [59°F-86°F]) and protected from light. After being frozen for 3 days and allowed to thaw at room temperature, the injectable product is physically stable. Midazolam is stable at a pH range of 3 to 3.6.
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
咪達唑侖是一種短效的注射用苯二氮平類藥物，在獸醫學中廣泛用作麻醉前鎮靜劑、肌肉鬆弛劑和抗癲癇藥物。
臨床要點：
- 獨特的溶解性： 與地西泮（Diazepam）不同，咪達唑侖在藥瓶中（pH < 4）呈水溶性，但在生理體液 pH 值（7.4）下會變得具有高度脂溶性。這使其能安全地與其他水溶性藥物（如鴉片類藥物和氯胺酮）混合而不會產生沉澱。
- 肌肉注射吸收： 由於不含丙二醇，咪達唑侖在肌肉注射（IM）時不會引起刺痛，且能迅速可靠地被吸收，因此在肌肉注射的應用上優於地西泮。
- 矛盾性興奮： 當單獨給予健康、無焦慮的犬貓時，咪達唑侖通常無法提供可靠的鎮靜效果，反而可能引起矛盾的煩躁或興奮。與其他藥物（如鴉片類、氯胺酮或 alpha-2 致效劑）合併使用時效果最佳。
- 癲癇重積狀態： 對於阻止活動性癲癇發作非常有效，可透過靜脈（IV）、肌肉（IM）或鼻腔（IN）給藥。
作用機制
Midazolam exerts its effects by enhancing the activity of gamma-aminobutyric acid (GABA), the primary inhibitory neurotransmitter in the central nervous system.
- Target: Binds to specific allosteric benzodiazepine receptors on the GABA-A receptor complex.
- Mechanism: Binding increases the frequency of chloride channel openings → influx of chloride ions → hyperpolarization of the postsynaptic neuronal membrane → decreased neuronal excitability.
- Effects: This depression of subcortical levels (limbic, thalamic, and hypothalamic) produces anxiolytic, sedative, skeletal muscle relaxant, and anticonvulsant effects. Midazolam has approximately twice the affinity for benzodiazepine receptors compared to diazepam, making it more potent with a faster onset and shorter duration of action.
安全性與警告
禁忌症
- Hypersensitivity to benzodiazepines
- Acute narrow-angle glaucoma
- Intra-carotid artery injection (must be avoided)
- Neonates (avoid use)
不良反應
- Respiratory depression (especially when combined with opioids or other CNS depressants)
- Paradoxical excitement, dysphoria, or agitation (especially in cats and dogs when used alone)
- Hypotension and bradycardia (when combined with other anesthetics like isoflurane or ketamine)
- Pain on injection or local irritation (rare compared to diazepam)
- Severe hypotension
- Paradoxical excitement (occasionally)
注意事項
High-Risk Patients: Use cautiously in patients with hepatic or renal disease, and in debilitated or geriatric patients.
- Cardiovascular/Respiratory: Administer with extreme caution to patients in coma, shock, or with significant respiratory depression. Patients with congestive heart failure may eliminate the drug more slowly.
- Anesthetic Combinations: While midazolam alone has minimal cardiorespiratory effects, combining it with opioids, ketamine, or inhalants can lead to significant respiratory depression, bradycardia, or hypotension.
- Pregnancy: FDA Category D in humans. May cause congenital abnormalities if used in the first trimester. Excreted in milk and may cause CNS effects in nursing neonates.
藥物相互作用
Midazolam may decrease the dosages required for inhalant anesthetics.
May inhibit midazolam metabolism, increasing midazolam blood levels.
May increase midazolam levels.
May increase midazolam levels by inhibiting hepatic metabolism.
May increase the risk of profound sedation and respiratory depression.
May increase midazolam levels.
May increase the hypnotic effects of midazolam; hypotension has been reported when used with meperidine. Combination causes greater respiratory depression.
May decrease peak levels and AUC of midazolam via enzyme induction.
May decrease peak levels and AUC of midazolam.
Midazolam may decrease the dosages required for induction.
Potentiates effect, reducing the dose required for induction
Potentiates effect, reducing the dose required
May enhance the sedative effect
May enhance the sedative effect
May enhance the sedative effect
May increase the hypnotic and hypotensive effects of midazolam; enhances sedation
Inhibits the metabolism of midazolam
監測
- Level of sedation and central nervous system depression
- Respiratory rate, effort, and oxygenation (especially when combined with other drugs)
- Heart rate and blood pressure
- Respiratory rate and effort
- Heart rate and rhythm
- Level of sedation and consciousness
藥物動力學
半衰期
吸收
Following IM injection, midazolam is rapidly and nearly completely (91%) absorbed. Oral absorption is good, but bioavailability is low (31-72%) due to a rapid first-pass effect. Rectal bioavailability in dogs is very low. Intranasal administration (especially via compounded gel) provides good absorption and high peak levels.
分佈
Highly protein bound (94-97%). Due to its high lipophilicity at physiologic pH, it rapidly crosses the blood-brain barrier. Changes in plasma protein concentrations can significantly alter the response to a given dose.
代謝
Metabolized in the liver, principally by microsomal oxidation. Forms an active metabolite (alpha-hydroxymidazolam), which has a very short half-life and negligible clinical effects.
排除
Eliminated primarily via hepatic metabolism and subsequent excretion. The duration of activity is considerably shorter than that of diazepam.
過量
Accidental overdoses should be managed with supportive care (e.g., cardiovascular and respiratory support), similar to diazepam.
- Reversal Agent: Flumazenil is a specific benzodiazepine antagonist and can be used to reverse midazolam's effects.
- However, because midazolam has a very short duration of effect and flumazenil is costly, supportive therapy is usually sufficient for all but the most massive overdoses.
可用產品
劑型
- Injection (solution)
- Oral syrup
- Injectable solution: 1 mg/ml, 2 mg/ml, 5 mg/ml
- Oromucosal solution: 5 mg/ml (in 0.5 ml, 1 ml, 1.5 ml, 2 ml pre-filled syringes)
- Oromucosal solution: 10 mg/ml pre-filled syringe
獸醫用
- None (No veterinary-labeled products currently available)
- Buccolam
- Epistatus
- Hypnovel
人用標示
- Midazolam HCl Injection: 1 mg/mL in 2 mL, 5 mL, 10 mL vials
- Midazolam HCl Injection: 5 mg/mL in 1 mL, 2 mL, 5 mL, 10 mL vials & 2 mL syringes
- Midazolam HCl Syrup: 2 mg/mL in 118 mL
- Buccolam
- Epistatus
- Hypnovel
各地核准狀態
POM
POM-V
暫無法規資料: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Store midazolam injection at room temperature (15°-30°C) and protect from light. It is physically stable after being frozen for 3 days and thawed. Midazolam is stable at a pH from 3-3.6. Compounded oral suspensions (e.g., with Syrpalta) retain >90% potency for 56 days when stored at 7°C, 20°C, or 40°C and protected from light.
飼主須知
注意： 咪達唑侖幾乎只在獸醫院內或在專業人員的直接監督下給藥。
- 用途： 您的寵物可能會接受此藥物，以幫助牠們在手術前放鬆、提供肌肉鬆弛，或迅速停止活動性癲癇發作。
- 行為改變： 如果單獨給藥，有些寵物（尤其是健康的犬貓）可能會暫時變得焦躁、發出嗚嗚聲或步態不穩，而不是變得想睡。這是已知的反應，且會很快消退。
- 安全性： 因為當它與其他麻醉劑結合使用時可能會影響呼吸和心跳速率，您的獸醫團隊會在藥物作用期間密切監測您寵物的生命徵象。
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