氟西汀
Fluoxetine
Fluoxetine hydrochloride
別名: Prozac · Reconcile · Sarafem · fluoxetini hydrochloridum · LY110140 · Fluoxetine 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
劑量為合格獸醫專業人員的臨床參考。請務必對照最新仿單及個別病患確認。
各物種劑量
🌎 NA — North America🌍 EU — Europe
狗
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Treatment of canine separation anxiety in conjunction with a behavior modification plan | 1-2 mg/kg PO once daily | PO | q24h | — | 🌎 NA |
| Separation anxiety and noise aversions | 1-2 mg/kg PO once daily | PO | q24h | Continue until 2 months after satisfactory response, then discontinue gradually | 🌎 NA |
| Adjunctive pharmacological intervention for conflict-related aggression | 1-2 mg/kg PO once a day | PO | q24h | — | 🌎 NA |
| Compulsive disorders | 1-2 mg/kg PO once daily | PO | q24h | — | 🌎 NA |
| Adjunctive treatment of behavior disorders | 1-1.5 mg/kg PO once daily | PO | q24h | — | 🌎 NA |
| Adjunctive treatment of behavior disorders | 1 mg/kg PO once daily (up to 3 mg/kg PO once daily) | PO | q24h | — | 🌎 NA |
| Separation anxiety, compulsive disorders, and aggression | 1-2 mg/kg | PO | q24h | Long-term as directed | 🌍 EU |
- Separation anxiety and noise aversions: Use with behavioral therapy. May use long-term. Some dogs require life-long treatment. May add a benzodiazepine during seasonal noise fears.
- Adjunctive pharmacological intervention for conflict-related aggression: May take up to 4 weeks for efficacy.
- Separation anxiety, compulsive disorders, and aggression: Use in association with a behaviour modification plan. Caution with aggression.
貓
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Adjunctive treatment of aggression | 0.5-1.5 mg/kg PO once daily | PO | q24h | — | 🌎 NA |
| To help control urine marking or separation anxiety | 0.5-1 mg/kg (2.55 mg per cat) PO once daily | PO | q24h | — | 🌎 NA |
| To control pruritus when other therapies have failed | 1-5 mg/cat PO once daily | PO | q24h | Assess therapy after 1-4 weeks. Taper off dose over 6-8 weeks. | 🌎 NA |
| Generalized anxiety disorder | 0.5-1.5 mg/kg PO once daily | PO | q24h | — | 🌎 NA |
| Urine spraying, psychogenic alopecia, and aggression | 0.5-1.0 mg/kg | PO | q24h | Long-term as directed | 🌍 EU |
- To control pruritus when other therapies have failed: Advise obtaining baseline lab work.
- Urine spraying, psychogenic alopecia, and aggression: Similar precautions for aggression apply as in dogs.
劑量為合格獸醫專業人員的臨床參考。請務必對照最新仿單及個別病患確認。
概覽
氟西汀 (Fluoxetine) 是一種廣泛使用的選擇性血清素再攝取抑制劑 (SSRI) 抗憂鬱藥，在獸醫學中用於治療犬貓的各種行為障礙。
在犬隻中，它已獲得 FDA 批准（商品名 Reconcile®），用於結合行為矯正計畫治療分離焦慮症。它也常被標示外用於攻擊行為、刻板行為（強迫症）和廣泛性焦慮。在貓咪中，常被處方用於不當排泄（尿液記號）、攻擊行為、焦慮和心因性脫毛/搔癢。
臨床要點： 氟西汀通常需要 4 到 8 週 的顯著滯後時間才能觀察到完整的臨床療效。這是因為突觸後受體向下調節需要時間。必須建議飼主在初期保持耐心並按時給藥。
作用機轉
Fluoxetine acts by selectively binding to and inhibiting the presynaptic serotonin transporter (SERT) in the central nervous system.
- Inhibition of Reuptake: Blockade of SERT prevents the reuptake of serotonin (5-HT) into the presynaptic neuron.
- Increased Synaptic Serotonin: This leads to an accumulation of serotonin in the synaptic cleft → prolonged activation of postsynaptic 5-HT receptors.
- Receptor Downregulation: Chronic elevation of synaptic serotonin eventually leads to the downregulation and desensitization of autoreceptors (e.g., 5-HT1A), which correlates with the onset of anxiolytic, anticompulsive, and anti-aggressive clinical effects.
Fluoxetine has minimal affinity for other neurotransmitter receptors (such as dopamine, norepinephrine, histamine, or acetylcholine), which accounts for its relatively favorable side effect profile compared to tricyclic antidepressants (TCAs).
安全性與警告
禁忌症
- Known hypersensitivity to fluoxetine
- Concurrent use of Monoamine Oxidase Inhibitors (MAOIs), including selegiline and amitraz (found in some tick collars)
- Patients with epilepsy or a history of seizures
- Concurrent use with drugs that lower the seizure threshold (e.g., acepromazine, chlorpromazine)
- Known sensitivity to fluoxetine or other SSRIs
- History of seizures or epilepsy
不良反應
- Anorexia or decreased appetite (common, often transient)
- Lethargy or depression
- Gastrointestinal upset (vomiting, diarrhea)
- Anxiety, irritability, or restlessness
- Insomnia or hyperactivity
- Panting (dogs)
- Changes in elimination patterns (cats)
- Paradoxical aggressive behavior (in previously unaggressive animals)
- Seizures (rare but possible)
- Weight loss
- Trembling
- Gastrointestinal disturbances
- Paradoxical increase in anxiety
- Increased aggression
注意事項
- Seizure Disorders: Use is contraindicated in patients with a history of seizures.
- Diabetes Mellitus: Use with caution as fluoxetine may alter blood glucose levels, necessitating insulin adjustments.
- Hepatic Impairment: Dosages may need to be reduced in patients with severe liver disease due to decreased clearance.
- Tapering: Because of the long half-life of the active metabolite (norfluoxetine), tapering off the drug is generally only necessary when a patient has been on the drug long-term (>8 weeks).
- Pregnancy/Nursing: Safety is not fully established (FDA Category C in humans). Excreted in milk at 20-30% of plasma levels; use caution in nursing animals.
藥物交互作用
Increased risk for serotonin syndrome
May decrease or reverse the effects of SSRIs (acts as a serotonin antagonist)
Fluoxetine may increase diazepam and alprazolam plasma levels
Increased risk for hyponatremia
May alter insulin requirements (can alter blood glucose)
Increased risk for serotonin syndrome
High risk for serotonin syndrome; use contraindicated. A 5-week washout is required after stopping fluoxetine before starting an MAOI, and a 2-week washout if switching from an MAOI to fluoxetine.
Serotonin syndrome-like adverse effects possible
Increased plasma levels of phenytoin possible
Fluoxetine may increase these beta-blocker's plasma levels; atenolol may be safer to use
SSRIs can inhibit the metabolism of tramadol to active metabolites, decreasing efficacy and increasing toxicity risk (serotonin syndrome, seizures)
Fluoxetine may increase TCA blood levels and increase the risk for serotonin syndrome
Increased plasma levels of trazodone possible
Fluoxetine may increase the risk for bleeding
Risk of fatal serotonin syndrome. Fluoxetine should not be used within 2 weeks of MAOI treatment, and MAOIs should not be used within 6 weeks of fluoxetine treatment.
Fluoxetine antagonizes the effects of anticonvulsants and lowers the seizure threshold.
Lowers seizure threshold, increasing the risk of seizures.
Increased risk of bleeding in the case of tissue trauma.
Increased risk of serotonin syndrome. Use alongside trazodone may be considered in exceptional cases only with careful monitoring.
Increased risk of serotonin syndrome.
監測
- Efficacy of the behavior modification plan and reduction of clinical signs
- Appetite and body weight (due to risk of anorexia)
- Signs of adverse effects (GI upset, lethargy, paradoxical aggression, seizures)
- Behavioral response and changes in aggression
- Signs of serotonin syndrome (tremors, agitation, hyperthermia)
- Gastrointestinal tolerance
藥物動力學
半衰期
吸收
Well absorbed after oral administration. In dogs, ~70% of an oral dose reaches systemic circulation. Food alters the rate, but not the extent, of absorption. Transdermal bioavailability in cats is poor (~10% of oral route).
分佈
Widely distributed throughout the body with highest levels in the lungs and liver. CNS concentrations are detected within 1 hour. Highly protein-bound (~95% in humans). Crosses the placenta and enters maternal milk (20-30% of plasma levels).
代謝
Primarily metabolized in the liver to a variety of metabolites, including the active metabolite norfluoxetine.
排除
Both fluoxetine and norfluoxetine are eliminated slowly. Renal impairment does not substantially affect elimination, but liver impairment decreases clearance rates.
過量
The LD50 for rats is 452 mg/kg.
Clinical Signs of Toxicity:
- Dogs: Vomiting, mydriasis (dilated pupils), lethargy, hyperactivity, and seizures. Seizures have been reported at doses twice the highest recommended human dose.
- Cats: Hypersalivation, vomiting, mydriasis, and excessive vocalization.
Treatment:
- Treatment is symptomatic and supportive.
- Gut emptying techniques (emesis, activated charcoal) should be employed if recent and not contraindicated (e.g., patient is seizing or comatose).
- Diazepam is the treatment of choice for controlling seizures.
- Cyproheptadine can be administered as a serotonin antagonist if serotonin syndrome is suspected.
可用產品
劑型
- Chewable tablets
- Oral capsules
- Oral solution
- Transdermal gel (compounded - note: poor bioavailability in cats)
- Oral tablets: 8 mg, 16 mg, 20 mg, 32 mg, 64 mg
獸醫用
- Fluoxetine Chewable Tablets: 8 mg, 16 mg, 32 mg, & 64 mg; Reconcile® (Lilly)
- Reconcile (8 mg, 16 mg, 32 mg, 64 mg chewable tablets)
人用標示
- Fluoxetine HCl Oral Tablets: 10 mg, 15 mg & 20 mg
- Fluoxetine HCl Oral Capsules: 10 mg, 20 mg, 40 mg & 90 mg (delayed-release); Prozac®, Sarafem®
- Fluoxetine HCl Oral Solution: 20 mg/5 mL (may contain alcohol, sucrose); Prozac®
- Prozac (10 mg, 20 mg, 60 mg capsules/tablets)
各地核准狀態
Veterinary formulation (Reconcile) is licensed within Europe.
POM-V, POM. Monograph notes veterinary formulation is not currently available in the UK, though human generics may be used under the cascade.
暫無法規資料: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Capsules and tablets should be stored in well-closed containers at room temperature. The oral liquid should be stored in tight, light-resistant containers at room temperature.
飼主須知
- 耐心是關鍵： 此藥物通常需要 4 到 8 週才能發揮最大效用。請勿因為沒有立即看到效果就停止給藥。
- 行為矯正： 當與獸醫師建議的行為矯正和訓練計畫結合使用時，氟西汀的效果最佳。
- 副作用： 最常見的副作用包括嗜睡、食慾不振、嘔吐、發抖、焦躁不安、腹瀉和過度鳴叫。如果這些症狀嚴重或持續存在，請聯繫您的獸醫師。
- 食慾減退： 如果您的寵物食慾下降，可以嘗試親手餵食或暫時增加食物的適口性（例如添加少量濕糧或低鈉肉湯）。
- 請勿突然停藥： 未經獸醫師指導，請勿突然停止使用此藥物，因為這可能會導致戒斷症狀或行為復發。
- 癲癇警告： 極少數情況下，犬隻在服用此藥物期間可能會出現癲癇發作。如果發生癲癇，請立即聯繫獸醫師。
- 防壁蝨項圈： 如果您使用防壁蝨項圈，請告知獸醫師，因為某些項圈含有雙甲脒 (amitraz)，與氟西汀結合使用時會引起危險的藥物交互作用（血清素症候群）。
- 請將此藥物存放在兒童和其他寵物接觸不到的安全地方。
VetSheet 藥物參考供合格獸醫專業人員作臨床決策輔助之用，不能取代專業判斷或廠商最新仿單。