クロルジアゼポキシドおよびクリジニウム
Chlordiazepoxide and Clidinium
Chlordiazepoxide hydrochloride; Clidinium bromide
別名: Librium · Librax · chlordiazepoxidi hydrochloridum · methamino-diazepoxide hydrochloride · NSC-115748 · Ro5-0690
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 |
|---|---|---|---|---|---|
| Behavior indications (thunderstorm/noise phobias) | 2.2-6.6 mg/kg | PO | as needed | — | 🌎 NA |
| Symptomatic treatment of irritable bowel syndrome | 0.1-0.25 mg/kg of clidinium or 1-2 capsules | PO | two times to three times a day | Discontinued in a few days | 🌎 NA |
| Symptomatic treatment of irritable bowel syndrome | 0.44-1.1 mg/kg of clidinium | PO | two to three times a day | 1 day to 2 weeks (some require long-term treatment at 1-2 doses per day) | 🌎 NA |
- Behavior indications (thunderstorm/noise phobias): Chlordiazepoxide alone; start low
- Symptomatic treatment of irritable bowel syndrome: Using the combination product (e.g., Librax). Give when abdominal pain or diarrhea first noticed or if stressful conditions are encountered.
- Symptomatic treatment of irritable bowel syndrome: Using the combination product (e.g., Librax). Use at first signs of cramping or abdominal pain.
猫
| 適応 | 用量 | 経路 | 頻度 | 期間 | 地域 |
|---|---|---|---|---|---|
| As an anxiolytic | 0.5-1 mg/kg | PO | q12-24h | — | 🌎 NA |
- As an anxiolytic: Chlordiazepoxide alone
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
クロルジアゼポキシドは、主に抗不安作用および軽度の鎮静作用を目的として使用される長時間作用型のベンゾジアゼピン系薬です。クリジニウム臭化物は、胃腸の運動や痙攣を抑える合成第四級アンモニウム抗ムスカリン（抗コリン）薬です。
獣医療では、これらの薬剤は単独または組み合わせて使用されることがあります：
- クロルジアゼポキシド単独：犬の音響恐怖症や、猫の猫同士の攻撃行動、尿スプレーなどの行動障害の補助療法として使用されます。
- クロルジアゼポキシド + クリジニウム (Librax®)：この配合剤は、犬の過敏性腸症候群 (IBS) などのストレス誘発性胃腸疾患の治療に独自の位置を占めています。中枢性の不安要素（クロルジアゼポキシドによる）と末梢性の胃腸痙攣（クリジニウムによる）の両方に対処します。
臨床のポイント：クリジニウムは第四級アミンであるため、血液脳関門を容易に通過せず、アトロピンでよく見られる中枢性の抗コリン性副作用を回避できます。
作用機序
The combination product exerts its effects through two distinct mechanisms targeting the central nervous system and the peripheral gastrointestinal tract:
- Chlordiazepoxide (Anxiolytic/Sedative): Binds to the benzodiazepine allosteric site on the GABA-A receptor complex in the CNS → enhances the affinity of the receptor for the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) → increases the frequency of chloride channel openings → neuronal hyperpolarization. This dampens activity in the limbic system, thalamus, and hypothalamus, producing anxiolytic, muscle relaxant, and anticonvulsant effects.
- Clidinium (Antispasmodic): Acts as a competitive antagonist at muscarinic acetylcholine receptors (primarily M3 receptors in the gut) → inhibits parasympathetic nerve impulses → significantly reduces gastrointestinal smooth muscle spasms, motility, and gastric acid secretion.
安全性・警告
禁忌
- Known hypersensitivity to benzodiazepines or antimuscarinics
- Coma, shock, or significant respiratory depression
- Aggressive patients (may disinhibit bite inhibition and worsen aggression)
- Tachycardia secondary to thyrotoxicosis or cardiac insufficiency
- Myocardial ischemia
- Gastrointestinal obstructive disease or paralytic ileus
- Severe ulcerative colitis
- Obstructive uropathy
- Myasthenia gravis
- Known or suspected GI infections (may prolong retention of toxins/pathogens)
有害事象
- Paradoxical CNS excitement or agitation (especially in dogs)
- Variable sedation and lethargy
- Behavioral changes (irritability, aberrant demeanor in cats)
- Potential hepatotoxicity (idiosyncratic hepatic failure reported with oral diazepam in cats; unknown if chlordiazepoxide shares this risk)
- Dry mouth (xerostomia)
- Constipation or dysphagia
- Urinary retention or hesitancy
- Tachycardia (at higher doses) or initial bradycardia
注意事項
Warning: Use benzodiazepines with extreme caution in aggressive animals, as they may disinhibit anxiety-based bite inhibition, leading to worsened aggressive behavior.
- Hepatic/Renal Impairment: Use cautiously in patients with liver or kidney disease, and in debilitated or geriatric patients.
- Working Animals: Benzodiazepines may impair the abilities of working or service animals.
- Autonomic Neuropathy: Use antimuscarinics with extreme caution.
- Pregnancy: Benzodiazepines are potentially teratogenic (FDA Category D). Use during the first trimester only if benefits clearly outweigh risks.
- Nursing: Distributed into milk and may cause CNS effects in nursing neonates.
医薬品相互作用
Pharmacologic effects of digoxin may be increased; clidinium may also increase serum levels of slow-dissolving digoxin.
Additive CNS depression and sedative effects.
May interfere with benzodiazepine metabolism in the liver, causing increased or prolonged effects.
May induce hepatic microsomal enzymes and decrease the pharmacologic effects of benzodiazepines.
May decrease the metabolism of chlordiazepoxide, leading to excessive sedation.
May decrease the metabolism of chlordiazepoxide, leading to excessive sedation.
May decrease the metabolism of chlordiazepoxide, leading to excessive sedation.
May decrease the metabolism of chlordiazepoxide, leading to excessive sedation.
May decrease chlordiazepoxide metabolism. Additionally, increased gastric pH from clidinium may decrease GI absorption of ketoconazole (administer clidinium 2 hours after ketoconazole).
May decrease the metabolism of chlordiazepoxide, leading to excessive sedation.
May decrease the metabolism of chlordiazepoxide, leading to excessive sedation.
May enhance the anticholinergic activity and toxicity of clidinium.
Antimuscarinics may aggravate signs of amitraz toxicity, leading to hypertension and further inhibition of peristalsis.
May decrease PO absorption of clidinium; give at least 1 hour prior to oral antacids.
Long-term use concurrently with antimuscarinics may increase intraocular pressure.
Clidinium and other antimuscarinics may antagonize the prokinetic actions of metoclopramide.
監視
- Clinical efficacy (reduction in anxiety, resolution of GI spasms/diarrhea)
- Adverse effects (excessive sedation, paradoxical excitement, anticholinergic signs)
- Baseline and periodic liver function tests in cats (due to idiosyncratic hepatotoxicity risks associated with oral benzodiazepines)
薬物動態
吸収
Chlordiazepoxide is rapidly absorbed following oral administration. Clidinium is incompletely absorbed from the small intestine.
分布
Chlordiazepoxide is highly lipid soluble, widely distributed, fairly highly bound to plasma proteins, and readily crosses the blood-brain barrier. Clidinium is completely ionized in vivo and does not appreciably cross into the CNS or the eye.
代謝
Chlordiazepoxide is metabolized in the liver to several active metabolites (desmethyldiazepam, desmethylchlordiazepoxide, oxazepam) which have considerable half-lives. Clidinium is metabolized principally in the liver.
消失
Both drugs and their metabolites are eliminated primarily in the urine.
過剰投与
Overdoses of chlordiazepoxide alone are generally limited to significant CNS depression (confusion, coma, decreased reflexes). Hypotension, respiratory depression, and cardiac arrest are possible but rare.
Treatment:
- Standard protocols for acute oral toxicity (gastric decontamination, binding agents like activated charcoal).
- Supportive systemic measures (fluids, cardiovascular support).
- Flumazenil may be considered as a specific reversal agent for severe benzodiazepine-induced CNS depression.
- Analeptic agents (CNS stimulants like caffeine) are generally not recommended.
製品
製剤
- Oral Capsules
ヒト用医薬品
- Chlordiazepoxide HCl Oral Capsules: 5 mg, 10 mg & 25 mg
- Chlordiazepoxide HCl 5 mg and Clidinium Br 2.5 mg Capsules (Librax®)
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
Chlordiazepoxide HCl capsules/tablets and combination capsules should be stored at room temperature in tight, light-resistant containers.
飼主向け情報
- 投与方法：獣医師の指示通りに正確に投与してください。ストレス関連の下痢に使用する場合は、痙攣の最初の兆候やストレスのかかる出来事があった時に投与してください。
- 行動の変化：一部の動物（特に犬）では、この薬が落ち着かせるどころか、逆説的な興奮や落ち着きのなさを引き起こすことがあります。ペットの行動が悪化したり、攻撃的になった場合は、すぐに獣医師に連絡してください。
- 副作用：口渇（常に新鮮な水が飲めるようにしてください）、便秘、または軽度の眠気を引き起こす可能性があります。
- 猫に関する注意：食欲不振、嘔吐、無気力、または目や歯茎の黄疸がないか注意深く観察してください。このクラスの経口抗不安薬は、まれに猫に肝臓の問題を引き起こす可能性があります。
- 安全性：子供や他のペットの手の届かないところに厳重に保管してください。密閉容器に入れて保管してください。
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。