西咪替丁
Cimetidine
別名: Zitac · Tagamet · Cimetidinum
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GI ulceration (extra-label)
- q8-12h
NA
必須同時考慮的臨床上下文 (1)
- Cimetidine products should be stored protected from light in airtight containers and kept at room temperature, 20°C to 25°C (68°F-77°F).
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
西咪替丁 (Cimetidine) 是一種組織胺 (H2) 受體拮抗劑，用於治療特發性、尿毒症或藥物引起的糜爛性胃炎、胃和十二指腸潰瘍、食道炎，以及繼發於胃泌素瘤、肥大細胞腫瘤或短腸症候群的胃酸分泌過多症狀。
臨床警告： 其對非類固醇抗發炎藥 (NSAID) 引起的潰瘍療效尚存爭議。與較新型的H2受體阻斷劑（如法莫替丁）和質子幫浦抑制劑（如奧美拉唑）相比，其降低胃酸的效果較弱。它具有極微弱的促腸胃蠕動作用，且不具備止吐效果。
作用機制
Acts as a Histamine (H2) receptor antagonist → competitively inhibits histamine at H2 receptors of the gastric parietal cells → reduces histamine-induced gastric acid secretion. It also binds to microsomal cytochrome P450 enzymes, retarding oxidative hepatic drug metabolism. It has weak anti-androgenic effects.
安全性與警告
禁忌症
- No specific contraindications available, but use with caution in patients with known hypersensitivity.
不良反應
- Thrombocytopenia (reported in dogs)
- Transient and self-resolving slight swelling of mammary glands (female dogs)
- Hepatotoxicity (rare, reported in humans)
- Nephrotoxicity (rare, reported in humans)
- Headache (humans)
- Decreased libido (humans)
注意事項
Warning: Rebound gastric acid secretion may be seen on cessation of cimetidine, so therapy should be tapered. Concomitant treatment with sucralfate may be helpful.
Warning: If used IV, should be administered slowly over 30 minutes to prevent cardiac arrhythmias and hypotension.
- Dosage should be reduced for animals with renal impairment.
藥物相互作用
Increases plasma levels of beta-blockers due to CYP450 inhibition
Increases plasma levels of calcium-channel blockers
Increases plasma levels of diazepam
Increases plasma levels of lidocaine
Increases plasma levels of metronidazole
Increases plasma levels of pethidine
Increases plasma levels of theophylline
May exacerbate leucopenia
May decrease cimetidine bioavailability; administer sucralfate at least 2 hours before
May decrease absorption; stagger oral doses by 2 hours
Altered absorption/metabolism; stagger oral doses by 2 hours
Decreased absorption of itraconazole due to reduced gastric acidity; stagger oral doses by 2 hours
Potential interaction; stagger oral doses by 2 hours
監測
- Clinical signs of GI ulceration or bleeding
- Renal function (to guide dose reduction if impaired)
- Heart rate and blood pressure (if administering IV)
- Complete blood count (monitor for thrombocytopenia or leucopenia, especially if on concurrent myelosuppressive drugs)
藥物動力學
半衰期
吸收
Rapidly absorbed with high bioavailability.
分佈
Widely distributed.
代謝
Undergoes hepatic metabolism. Retards oxidative hepatic drug metabolism by binding to the microsomal cytochrome P450.
排除
Renal excretion.
過量
Adverse reactions are generally minor even at high doses. Supportive care should be provided if massive overdose occurs.
可用產品
劑型
- Injectable: 100 mg/ml solution in 2 ml ampoule
- Oral: 100 mg tablets
- Oral: 200 mg tablets
- Oral: 40 mg/ml syrup
獸醫用
- Zitac
人用標示
- Tagamet
- Cimetidine generics
各地核准狀態
Available as human generic OTC and Rx.
POM-V, POM
POM-V, POM
暫無法規資料: 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Normal precautions should be observed. Store at room temperature away from light and moisture.
飼主須知
西咪替丁用於治療胃潰瘍、胃酸逆流以及胃酸分泌過多的情況。
- 請勿突然停藥，因為這可能會導致胃酸反彈性大量分泌。在停止治療時，您的獸醫通常會指示您逐漸減少劑量。
- 如果您同時給予硫糖鋁 (Sucralfate)、制酸劑或其他特定藥物，請至少間隔2小時給藥，以確保兩種藥物都能被正確吸收。
- 副作用很少見，但如果您發現任何異常跡象，例如不明原因的瘀傷（可能表示血小板低下）或母狗的乳腺腫脹，請聯繫您的獸醫。
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