氯硝西泮 (可洛那西泮)
Clonazepam
5-(2-chlorophenyl)-7-nitro-1,3-dihydro-1,4-benzodiazepin-2-one
別名: Klonopin · Antelepsin · Clonagin · Clonapam · Clonax · Clonex · Diocam · Epitril · Iktorivil · Kenoket · Kriadex · Neuryl · Paxam · Rivatril · Rivotril · Solfidin · Linotril · clonazepamum · Ro-5-4023
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 |
|---|---|---|---|---|---|
| Adjunctive medication in the treatment of seizures | 1-2 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
| Adjunctive medication in the treatment of seizures | 0.5 mg/kg PO two to three times a day | PO | q8-12h | — | 🌎 NA |
| Anxiolytic | 0.05-0.25 mg/kg PO q12-24h | PO | q12-24h | — | 🌎 NA |
| Anxiolytic | 0.1-1 mg/kg PO two to three times a day | PO | q8-12h | — | 🌎 NA |
| Muscular hypertonicity (episodic falling) / Anxiolytic | 0.5 mg/kg | PO | q8-12h | — | 🌍 EU |
- Adjunctive medication in the treatment of seizures: May need to lower phenobarbital dose by 10-20%
- Muscular hypertonicity (episodic falling) / Anxiolytic: Suggested starting dose but there is a wide range of recommendations.
貓
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Anxiolytic | 0.05-0.25 mg/kg PO q12-24h | PO | q12-24h | — | 🌎 NA |
| Anxiolytic | 0.02-0.2 mg/kg PO once to two times a day | PO | q12-24h | — | 🌎 NA |
| Anxiolytic | 0.1-0.2 mg/kg PO as needed or up to two times a day | PO | PRN or q12h | — | 🌎 NA |
| Adjunctive medication in the treatment of seizures | Starting dose is 0.5 mg (total dose) PO q12-24h | PO | q12-24h | — | 🌎 NA |
| Adjunctive medication in the treatment of seizures | 1/8th to 1/4 of a 0.5 mg tablet PO two to three times daily | PO | q8-12h | — | 🌎 NA |
| Anxiolytic / Hyperaesthesia / Epilepsy | 0.5 mg/cat | PO | q12-24h | — | 🌍 EU |
- Adjunctive medication in the treatment of seizures: Anecdotally more effective for maintenance and to decrease cluster seizures; acute hepatic necrosis possible
- Anxiolytic / Hyperaesthesia / Epilepsy: Suggested starting dose but there is a wide range of recommendations.
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
氯硝西泮 (Clonazepam) 是一種強效、長效的苯二氮平類 (Benzodiazepine) 藥物，在獸醫學中主要用作輔助性抗癲癇藥和抗焦慮藥。
臨床要點：在犬隻中，作為長期維持性抗癲癇藥的實用性非常有限，因為牠們會迅速對其抗癲癇效果產生耐受性（通常在 1 到 4 週內）。這是由於受體下調和藥代動力學改變所致。因此，它更適合用於短期脈衝治療或叢集性癲癇發作的管理。
- 在貓中，它可用於較長期的癲癇或焦慮輔助治療。雖然口服苯二氮平類藥物（最著名的是地西泮）在貓身上有引發特異體質性急性肝壞死的已知風險，但一般認為氯硝西泮發生此情況的可能性較低，不過仍需進行監測。
- 由於具有人類濫用和成癮的潛力，氯硝西泮屬於第四級管制藥品 (C-IV)。
作用機制
Clonazepam acts as a positive allosteric modulator at the GABA-A receptor complex in the central nervous system.
- It binds to specific benzodiazepine receptors (located primarily in the limbic, thalamic, and hypothalamic regions) → enhances the affinity of the receptor for the inhibitory neurotransmitter gamma-aminobutyric acid (GABA).
- This increases the frequency of chloride channel opening → influx of chloride ions → cellular hyperpolarization → decreased neuronal excitability.
- Additional postulated mechanisms include antagonism of serotonin and diminished release or turnover of acetylcholine in the CNS.
安全性與警告
禁忌症
- Hypersensitivity to clonazepam or other benzodiazepines
- Significant liver disease or dysfunction
- Acute narrow-angle glaucoma
- Myasthenia gravis (may exacerbate weakness)
- Marked CNS depression
- Respiratory depression
- Severe muscle weakness
- Hepatic impairment (may worsen hepatic encephalopathy)
不良反應
- Sedation and lethargy
- Ataxia (incoordination)
- Paradoxical excitement, hyperactivity, or vocalization
- Increased salivation
- Gastrointestinal upset (vomiting, diarrhea, constipation)
- Dogs: Rapid tolerance to anticonvulsant effects
- Cats: Polyphagia, potential for acute hepatic necrosis (rare)
- Respiratory suppression (at higher doses)
- Acute hepatic necrosis (idiosyncratic in cats)
- Tolerance development
注意事項
Do not discontinue therapy abruptly, especially in patients on chronic or high-dose therapy, as this may precipitate withdrawal signs or status epilepticus; taper the dose gradually. Use with caution in nursing dams, as benzodiazepines can enter milk and accumulate to toxic levels in neonates. Monitor cats closely for signs of hepatotoxicity.
藥物相互作用
May increase clonazepam levels by inhibiting its metabolism.
May decrease the metabolism of benzodiazepines, increasing their effects.
Additive CNS depression; may cause profound sedation or respiratory depression.
May decrease the metabolism of benzodiazepines.
May decrease clonazepam concentrations via hepatic enzyme induction.
May decrease clonazepam concentrations.
May decrease clonazepam concentrations.
May induce hepatic microsomal enzymes and decrease the pharmacologic effects of benzodiazepines.
Inhibition of CYP450 enzymes may decrease clonazepam clearance, increasing its plasma levels and risk of toxicity.
Additive sedation and respiratory depression.
監測
- Clinical efficacy (seizure frequency, anxiety levels)
- Adverse effects (sedation, ataxia, paradoxical excitement)
- Therapeutic blood levels (reported target: 0.015-0.07 mcg/mL)
- Cats: Baseline and periodic liver function tests
- Degree of sedation and ataxia
- Respiratory rate and effort
- Hepatic function panel (especially in cats)
- Clinical response (seizure frequency, muscle tone, or behavioral changes)
藥物動力學
半衰期
吸收
In dogs, oral bioavailability is variable (20-60%) but absorption is rapid. In humans, it is well absorbed from the GI tract with peak serum levels occurring about 3 hours after oral dosing.
分佈
Highly lipophilic; rapidly crosses the blood-brain barrier and placenta. Protein binding in dogs is approximately 82%.
代謝
Metabolized in the liver to several metabolites. In dogs, clonazepam exhibits saturation kinetics, meaning elimination rates are dose-dependent.
排除
Metabolites are excreted primarily in the urine.
過量
Overdoses commonly cause profound sedation, depression, and ataxia.
- Paradoxical Reactions: Some animals may exhibit paradoxical signs such as hyperactivity, disorientation, agitation, and vocalization. Paradoxical excitation can be treated with a mild sedative, such as diphenhydramine.
- Management: Emesis is generally NOT indicated due to the risk of rapid CNS depression and aspiration. Mild to moderate overdoses can often be monitored at home if the animal is rousable and not showing paradoxical signs. Keep the animal confined and minimize stimulation.
- Severe Toxicity: Massive overdoses can lead to respiratory depression or hypotension. Flumazenil (a specific benzodiazepine antagonist) can be used to reverse severe respiratory or CNS depression. Because flumazenil has a short half-life, multiple doses may be required.
可用產品
劑型
- Oral tablets
- Orally disintegrating tablets (ODT)
- Compounded oral suspension
- 0.25 mg tablet
- 0.5 mg tablet
- 1.0 mg tablet
- 2 mg tablet
- 500 mcg tablet
- 500 mcg/5 ml oral solution
- 2 mg/5 ml oral solution
人用標示
- Clonazepam Oral Tablets: 0.5 mg, 1 mg, & 2 mg (Klonopin, generic)
- Clonazepam Orally Disintegrating Tablets: 0.125 mg, 0.25 mg, 0.5 mg, 1 mg & 2 mg (Klonopin Wafers, generic)
- Linotril
- Rivotril
各地核准狀態
POM (Prescription Only Medicine). Subject to national controlled drug regulations.
POM. Prescriptions are subject to controlled drug requirements.
暫無法規資料: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Tablets should be stored in airtight, light-resistant containers at room temperature. Compounded oral suspensions (0.1 mg/mL in Ora-Plus/Ora-Sweet) retain >90% potency for 60 days when stored at 5°C or 25°C, but must be protected from light.
飼主須知
- 按時服藥至關重要：抗癲癇治療失敗的一個主要原因是未按醫囑服藥。在規定的時間規律給藥非常重要。
- 切勿突然停藥：在沒有獸醫指導的情況下，絕對不要突然停止使用此藥物。突然停藥可能引發嚴重、危及生命的持續性癲癇發作（癲癇重積狀態）。如果需要停藥，您的獸醫會提供漸進式減量計畫。
- 副作用：剛開始服藥時，輕微的嗜睡和步態不穩很常見，但通常會逐漸改善。如果您的寵物變得異常過動或焦躁，請聯繫您的獸醫。
- 貓咪飼主注意事項：密切觀察您的貓咪是否出現食慾不振、嘔吐或眼白/牙齦發黃（黃疸）。這些可能是罕見但嚴重的肝臟問題的徵兆。如果您注意到這些跡象，請立即聯繫您的獸醫。
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