preanesthesia, local anesthetics, anti-convulsant Flashcards

1
Q

antidote for alpha2-agonist

A

yohimbine, tolazoline, atipamezole

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2
Q

clonidine

A
  1. 藥理機制:α2 receptor致效劑,receptor在CNS、心血管、腎、GI都有
  2. 臨床用途:降血壓
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3
Q

comparing the relationship of E on alpha2-agonist and phenothiazine

A
  1. alpha2-agonist: increase the sensitivity of E towards heart –> 當動物受到驚嚇時,產生內生性Epinephrine,會使心臟心律不整arrythmia
  2. Phenothiazines: as alpha receptor being blocked, E reversal occurs. so it increase te effect of E on beta receptor, causing stimulation on heart and hypotension. E and phenothiazines could not be used together (E is exogenous here)
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4
Q

what is the nature/mechanism of local anesthesia

A
  1. 作用機制:Na+ channel blocker!!! 阻斷神經纖維的Na+ channel,因此神經細胞無法depolarization,action potential is then blocked,痛覺就無法傳遞
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5
Q

Absorption and metabolism of local anesthetics

A
  1. 吸收越好,全身性毒性(systemic toxicity) 越高,所以LA吸收越差越好
  2. Epinephrine讓血管收縮,降低全身性吸收及毒性
  3. Ester類的LA容易被組織和血液中的esterase水解,新生動物的esterase功能不好,比較容易造成毒性
  4. Amide類的LA則是經由肝臟代謝,尿液排除
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6
Q

Toxicity of local anesthetics

A
  1. 注射部位的毒性:刺激局部組織irritation,造成損傷damage
  2. CNS毒性:較敏感,尤其LA打在大血管附近的神經時。可能造成興奮、意志、癲癇發作,因為血液中LA濃度變高抑制cortical inhibitory pathway(Na channel blockage)

※LA造成的癲癇發作時,因為沒有拮抗劑,所以要給抗癲癇藥物(diazepam快速IV注射)以及提供氧氣

  1. 心血管毒性:敏感度小於中樞,因此毒性出現比中樞慢。LA會直接干擾心肌細胞傳導收縮,可造成心律不整。同時也會造成血管擴張、血壓下降,綜合下來的結果可能會造成心跳停止。

※心血管功能降低時給予輸液、氧氣、CPR、α-agonist

  1. 神經傷害chloroprocaine因為配方要加入抗氧化劑sodium bisulfite,而這個抗氧化劑對神經有傷害,劑量越高越容易出現
  2. 骨骼肌:造成局部刺激
  3. Methemoglobinemia變性血紅素血症Prilocaine的代謝物ο-toluidine有氧化活性,會使血紅素中的Fe2+氧化成Fe3+(無法攜帶氧氣)
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7
Q

磺胺藥和which local anesthetics不能並用, why?

A
  1. Procaine, benzocaine: local anesthetics
  2. sulfanilamide: inhibit bacterial growth by preventing the bacteria from obtaining PABA, which is essential in cell division
  3. 水解代謝物of procaine:PABA,是細菌合成葉酸的材料,因此會干擾磺胺藥(sulfanilamide) 抑制細菌合成葉酸的效果。所以磺胺藥和procaine不能並用
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8
Q

Which local anesthetic most easily cause systemic toxicity?

A
  1. Tetracaine
    1. 特殊的ester藥物,因為結構大,脂溶性高,不容易被水解
    2. 藥效強、作用時間長
    3. 因為不易水解,最容易出現全身性毒性
    4. 苯環上多了四個碳
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9
Q

local anesthetics of the least toxicity

A
  1. Prilocaine
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10
Q

Local anesthetics that is also an Antiarrhythmic agent

A

Lidocaine

  1. 可以做成溶劑 (solution) 或凝膠 (gel)
  2. 適用於所有LA的給藥方式
  3. 可以搭配Epinephrine延長藥效
  4. Antiarrhythmic agent via IV injection抗心律不整的用藥LA中只有他
  5. 肝臟代謝、尿液排除
  6. 牙科最常使用的LA
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11
Q

EMLA

A

EMLA (Eutectic Mixture of Lidocaine and Prilocaine)

  1. LidocainePrilocaine以1:1共溶為乳劑 (emulsion)
  2. 適合表皮塗抹給藥 (transcultaneous application)
  3. 藥效有60min,方便採血、打針(venipuncture)
  4. 除非過量不然不會有毒性
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12
Q

which local anesthetics could be used in fish?

A

benzocaine, tricaine

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13
Q

Procaine

A
  1. 在發現古柯鹼cocaine有毒性後,開發出的純化學合成藥
  2. 容易被組織的esterase分解,因此不能塗抹給藥,必須局部浸潤(infiltration) / neural block!
  3. 沒有刺激性
  4. 藥效很短,需要搭配Epinephrine(血管收縮)使用
  5. 毒性低
  6. 水解代謝物:PABA,是細菌合成葉酸的材料,因此會干擾磺胺藥(sulfanilamide) 抑制細菌合成葉酸的效果。所以磺胺藥和procaine不能並用
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14
Q

benzocaine

A
  1. 牙科常用
  2. 噴霧狀藥物噴在喉嚨(spray for intubation),減少麻醉插管造成的氣管疼痛
  3. 也會產生PABA
  4. 泡成水溶液,造成水生動物全身麻醉 for weighing, injection
  5. concentration is very important
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15
Q

chloroprocaine

A

Ester local anesthestics

  1. 因為結構中有Cl,藥效是Procaine的三倍
  2. 可脊椎注射(epidural route),用於產科的麻醉(obstetrical anesthesia)
  3. 藥效快、作用時間短,雖然脊椎注射會隨著CSF帶到大腦,但是一進到血液就會被分解 (due to ester in nature, easily hydrolyzed),所以毒性小
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16
Q

tetracaine

A
  1. 特殊的ester藥物,因為結構大,脂溶性高,不容易被水解
  2. 藥效強、作用時間長
  3. 因為不易水解,最容易出現全身性毒性
  4. 圖示:苯環上多了四個碳
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17
Q

Tricaine Mesylate(MS-222)

A
  1. 結構類似局部麻醉劑,但是一種鹽類,用於麻醉有鱗片的魚
  2. [for immobilization, anesthesia or sedation]
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18
Q

Lidocaine

A

amide 類別的!!!!

  1. 可以做成溶劑 (solution) 或凝膠 (gel)
  2. 適用於所有LA的給藥方式
  3. 可以搭配Epinephrine延長藥效
  4. Antiarrhythmic agent via IV injection抗心律不整的用藥LA中只有他
  5. 肝臟代謝、尿液排除
  6. 牙科最常使用的LA
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19
Q

prilocaine

A
  1. 類似Lidocaine
  2. 對vasodilation影響最低,因此最適合用IV給藥
  3. 毒性最小最安全
  4. 過量使用時代謝物ο-toluidine會造成變性血紅素血症methemoglobinemia
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20
Q

Bupivacaine

A
  1. 藥效是Lidocaine的4倍
  2. 局部浸潤或脊椎注射給藥
  3. 適合用在產科(obstetrical use):因為低劑量下對痛覺抑制好,而對運動功能抑制輕微 (separation between sensory and motor blockage)
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21
Q

Etidocaine

A
  1. 效果類似Bupivacaine但比較差 (little separation)
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22
Q

Ropivacaine

A
  1. 效果類似Bupivacaine,
  2. Route of administration: epidural
  3. Shorter and less motor blockage
  4. 但脂溶性比較差、藥效比較短,毒性更低
  5. Lower cardiac toxicity than bupivacaine
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23
Q
  1. Tonic-clonic(grand mal) seizure
  2. Absence(petit mal) seizure
  3. Myoclonic seizure
  4. Atonic seizure
  5. Status epilepticus
A
  1. Tonic-clonic(grand mal) seizure:大發作,會失去意識,是狗主要發作類型,也是獸醫最常需要處理的動物問題,
  2. Absence(petit mal) seizure:小發作,失神性發作,通常持續5~30秒,很像被點穴
  3. Myoclonic seizure:肌陣攣性發作,肌肉會亂收縮,病灶在motor cortex發生異常
  4. Atonic seizure:失張力發作,會因失去muscle tone而突然跌倒

Status epilepticus:癲癇重積症,最嚴重,會超過30min持續性癲癇,中間都沒有恢復意識

24
Q

SCN1A

A
  1. 這個基因下游製造的蛋白質就是組成Na+ channel的一部份。被這個基因轉殖的小鼠在出生後第三周就會癲癇發作,3個月內有40%會死亡
  2. 基因轉殖,目前已經找到SCN1A是跟癲癇有關的基因 for 癲癇藥物開發
  3. 實例:受到光刺激就會誘發癲癇的小鼠;聽到特定聲音就會癲癇的狒狒
25
Q

Phenobarbital

A
  1. 藥理機制:加長GABAA打開的時間
  2. 藥物效果:
  3. 適合控制癲癇,80%的犬類可以獲得控制,貓也可以使用
  4. 對大發作、部分發作有效
  5. 藥效太慢,不適合用在癲癇重積症
    1. 副作用:
      1. 誘導酵素P450產生
      2. 影響賀爾蒙(estrogens, androgens, thyroid hormones)
      3. 有肝毒性,禁用在有嚴重肝病的動物
      4. 吃多喝多尿多,抑制腦下垂體分泌ADH,導致多尿
      5. 出現麻醉效果,鎮靜、運動失調等
      6. 降低新生鼠的大腦發育,因此用於懷孕母畜要小心 (prenatal exposure influences sexual development in rats)
26
Q

Primidone

A

Phenobarbital的前驅物 【dogs only】

  1. 藥理機制:加長GABAA打開的時間
  2. 藥物效果:同Phenobarbital
  • 適合控制癲癇,80%的犬類可以獲得控制,貓也可以使用
  • 對大發作、部分發作有效
  • 藥效太慢,不適合用在癲癇重積症
  1. 注意事項: 無法轉換Primidone成Phenobarbital,而且肝功能比較不好,會有肝毒性,因此在貓不可使用
  2. 狗:可以用於維持
27
Q

Benzodiazepines

A

癲癇重積症首選用藥

  1. 藥理機制:提高GABAA打開的頻率
  2. 藥物效果:
    1. 適合用在急性癲癇重積症
    2. Not suitable for long-term maintenanc_e容易產生耐受性_tolerance to anticonvulsant effect,容易產生耐受性,在貓還勉強可以用於維持,在狗就完全不行
    3. Lorazepam
      1. 比較能用在狗的短時間維持
      2. 肝代謝快,no active metabolite,適用於肝功能低下的動物
    4. Clonazepam可以降低巴比妥鹽類的用量
    5. Midazolam的代謝物也有活性
  3. 副作用:
    1. 鎮定、疲勞、運動失調(BZD仍有術前給藥的作用)
    2. Diazepam:在貓導致行為異常、急性肝臟壞死
    3. Midazolam:輕微呼吸抑制,嘔吐、焦慮
    4. Clonazepam:嘔吐、流口水、腸胃道症狀
    5. Lorazepam:食慾增加、興奮、焦慮
28
Q

Phenytoin

A
  1. hydantoin derivatives
    1. 藥物機制:Na+ channel blocker(開一次後,無法回到resting stage), stabilizing neural membrane
    2. 藥物效果:broad spectrum
      1. 抗心律不整 antiarrhythmic
      2. 除了失神性癲癇,其他癲癇類型都能抑制
      3. 沒有鎮靜效果 [not GABA acting]
    3. 副作用:
      1. 狗:肝毒性 hepatoxicity in dogs
      2. 狗:牙齦增生gingival growth
      3. 狗: 影響狗的中樞系統,狗會昏沉drowsiness、厭食anorexia、嘔吐vomitting、共濟失調ataxia
      4. 致畸胎 (teratogenic effect): Fetal hydantoin syndrome,兔唇cleft palate
    4. 藥物動力學:
      1. 半衰期在動物範圍太大,貓 (42-108hr太長,增加中毒風險)、狗 (3-7hr太短,效果太差),難以維持適當濃度,只會在其他藥物都無效時當後線藥物
      2. rarely used in small animals as a result
      3. 誘導P450酵素產生,代謝提升、降低半衰期
      4. 代謝會被其他藥物影響:Carbamazepine使代謝提升;Cimetidine使代謝下降(因為抑制了P450)
29
Q

Lorazepam

A
  1. Benzodiazepines:癲癇重積症首選用藥
    1. 藥理機制:提高GABAA打開的頻率
    2. 藥物效果:
      1. 適合用在急性癲癇重積症
      2. Not suitable for long-term maintenance容易產生耐受性tolerance to anticonvulsant effect,在貓還勉強可以用於維持,在狗就完全不行
      3. Lorazepam
        1. 比較能用在狗的短時間維持
        2. 肝代謝快,no active metabolite,適用於肝功能低下的動物
    3. 副作用:
      1. 鎮定、疲勞fatigue (but some may be excited on the contrary)、運動失調ataxia (BZD仍有術前給藥的作用)
      2. Lorazepam:initially食慾增加、興奮、焦慮
30
Q

clonazepam

A
  1. Benzodiazepines:控制肌痙攣性癲癇​
    1. 藥理機制:提高GABAA打開的頻率
    2. 藥物效果:
      1. 適合用在控制肌痙攣性癲癇 (for clonazepa,m)
      2. Not suitable for long-term maintenance容易產生耐受性tolerance to anticonvulsant effect,在貓還勉強可以用於維持,在狗就完全不行
      3. Clonazepam可以降低巴比妥鹽類的用量
    3. 副作用:
      1. 鎮定、疲勞fatigue (but some may be excited on the contrary)、運動失調ataxia (BZD仍有術前給藥的作用)
      2. Clonazepam:嘔吐、流口水、腸胃道症狀
31
Q

Midazolam

A
  1. Benzodiazepines:癲癇重積症首選用藥
    1. 藥理機制:提高GABAA打開的頻率
    2. 藥物效果:
      1. 適合用在急性癲癇重積症
      2. Not suitable for long-term maintenance容易產生耐受性tolerance to anticonvulsant effect,在貓還勉強可以用於維持,在狗就完全不行
      3. Midazolam的_代謝物也有活性_
    3. 副作用:
      1. 鎮定、疲勞fatigue (but some may be excited on the contrary)、運動失調ataxia (BZD仍有術前給藥的作用)
      2. Midazolam:輕微呼吸抑制,嘔吐、焦慮
32
Q

diazepam

A
  1. Benzodiazepines:癲癇重積症首選用藥
    1. 藥理機制:提高GABAA打開的頻率
    2. 藥物效果:
      1. 適合用在急性癲癇重積症
      2. Not suitable for long-term maintenance容易產生耐受性tolerance to anticonvulsant effect,在貓還勉強可以用於維持,在狗就完全不行
    3. 副作用:
      1. 鎮定、疲勞fatigue (but some may be excited on the contrary)、運動失調ataxia (BZD仍有術前給藥的作用)
      2. Diazepam在貓導致行為異常、急性肝臟壞死(acute liver necrosis)
33
Q

which BZD may cause acute liver necrosis in cats

which BZD is toxic to liver as side effect

Which BZD may cause Fetal hydantoin syndrome

Which BZD is better for 肝臟功能不好的動物

A

acute liver necrosis: diazepam

Hepatitoxicity: phenytoin

致畸胎 (teratogenic effect): Fetal hydantoin syndrome,兔唇cleft palate: Phenytoin

肝臟功能不好的動物:Lorazepam (no active metabolite)

34
Q

Lorazepam

A

BZD (so similar effect)

經由glucuronidation代謝,腎排除

no active metabolite. 適合肝臟功能低下的患者

35
Q

What dizepam derivaties are suitable for 肝功能底下的病患呢

A

Lorazepam和Oxazepam

經由glucuronidation代謝,腎排除;不會產生活性代謝物的藥品

  1. 修正行為 (anxiolytic effects)
  2. 犬貓:治療恐懼(fear)、恐慌(phobia)、亂尿尿、分離焦慮(separation anxiety)
  3. 貓:增加食慾,常用DiazepamOxazepam
  4. 雪貂(mink):降低焦慮和攻擊性以促進繁殖
36
Q

Compare the metabolism and prodcut of

lorazepam, oxazepam, diazepam, alprazolam, chlordiazepoxide, clorazepate

PS they are all BZDs

A

Lorazepam / Oxazepam

  • glucuronidation代謝,腎排除; no active metabolite

Diazepam

  • CYP450代謝
  • 有active metabolite,為Desmethyldiazepam (nordiazepam),半衰期長(於貓21 h,於狗7 h)

Alprazolam

  • CYP450代謝
  • no active metabolite
  • 藥效產生快速;可與抗憂鬱劑一起使用

chlordiazepoxide

  • 有,為demoxepam和Nordiazepam,半衰期長

Clorazepate

  • 口服經過胃被胃酸氧化成Nordiazepam,再被消化道吸收
  • 有,為Nordiazepam
37
Q

Clorazepate

A

BZD - anxiolytics

rapid onset, can TCA/SSRI being combined

口服經過胃被胃酸氧化成Nordiazepam,再被消化道吸收

有,為Nordiazepam

38
Q

dizepam

A

會導致有些貓嚴重肝臟壞死 (active metabolites)

CYP450代謝

Desmethyldiazepam (nordiazepam) as metabolite,半衰期長(於貓21 h,於狗7 h)

39
Q

Alprazolam

A
  • BZD (anxiolytic)
  • fast onset of pharm effect, 可與抗憂鬱劑一起使用

肝臟CYP450代謝; no active metabolite

40
Q

nordiazepam

A

為Desmethyldiazepam (nordiazepam),半衰期長(於貓21 h,於狗7 h)

metabolites of diazepam; chlordiazepoxide and chlorazepate

41
Q

三環抗憂鬱劑

  1. mechanism
  2. onset time
  3. side effect
  4. metabolism
  5. contraindications
A
  1. 機制:阻斷5-HT & NE reuptake (沒有阻斷DA reuptake)
  2. NE和心情也有關,若缺乏NE會昏昏欲睡、沒精神
  3. 包含Imipramine, Clomipramine, Amitriptyline, Doxepin
  4. 在人醫常用,在獸醫為標籤外用藥;有70%的臨床有效率
  5. 要3週後才開始發揮藥效
  6. 之後被SSRI取代

Side effect (in normal dorsage)

  1. anti-muscarinic: urine retention, 視力模糊, 口乾舌燥、便祕
  2. alpha-blocking: 姿態性低血壓

Metabolism

  1. 避免併用Cimetidine, Ketoconazole (抗黴菌、影響内分泌hormone), Chloramphenicol等抑制P450藥物
  2. 肝功能低下者要小心,像是年老的動物肝功能差 – 劑量調整

Contraindication

  1. 青光眼 (narrow-angle glaucoma) ,因為TCA會有anti-cholinergic的效果,會使瞳孔擴大,青光眼眼_內壓會高_,應該要使用cholinergic縮瞳效果的藥品。
  2. 乾眼性結膜炎 (keratoconjunctivitis sicca)
  3. 劑量太高會造成(heart disease)cardiomyopathies & ECG 不正常
    • 因為TCA為anti-cholinergic影響心臟功能(increase heart rate)
    • TCA為 quinidine-like,quinidine用於處理心律不整
42
Q

Clomipramine

A
  1. TCA中最具選擇性的5-HT reuptake inhibitor
  2. FDA approval: 用於犬的分離焦慮症 (separation anxiety)
  3. 其他用途還有:治療追尾巴行為、口舔致皮膚炎(lick dermatitis)、心因性脫毛(psychogenic alopecia)
  4. 代謝產物desmethylclomipramine:
  • 具更強的antimuscarinic effect
  • Conjugation的過程在 較緩慢, leading to
  • 血中濃度維持較高,因此副作用較強
  • 消化道症狀、散瞳mydriasis、食慾改變等副作用較強 (anti-muscarinic effect)
43
Q

what drugs interact with TCA?

A
  1. MAO inhibitors → 導致serotonin syndrome(serotonin is non-reuptaked and metabolized, leading to an excess amount of 5-HT)!
  2. 鎮定藥物 → 加強鎮定效果
44
Q

Comparing BZD and TCA

A
  1. BZD treats seizure, while TCA對於有癲癇發作傾向的動物(predisposed animals)會降低癲癇的threshold
  2. BZD has disinhibition effect (leading to overexcitemnt in some animals), while TCA doesn’t.
45
Q

desmethylclomipramine

A

Metabolite of clomipramine

  • 具更強的antimuscarinic effect
  • Conjugation的過程在 貓 較緩慢, leading to
  • 血中濃度維持較高,因此副作用較強
  • 消化道症狀、散瞳mydriasis、食慾改變等副作用較強 (anti-muscarinic effect)
46
Q

imipramine

A

TSA (5HT-reuptake inhibitor)

  1. 犬貓:治療尿失禁(urinary incontinence)
    1. _Anti-muscarinic effects_放鬆膀胱平滑肌
    2. NE 活化bladder spinsters’ α受體,使其收縮
  2. 種馬stallion:治療射精功能異常 (ejaculatory dysfunction)
  3. 藥物使用會造成oxidative damage出現hemolysis → 紅血球破裂和尿液顏色改變
47
Q

Doxepin

A

TSA

unique 特性

  1. antipruritic effects:加強 H1 & H2 inhibitory effects (H1為 histamine 受體,histamine 和皮膚發炎反應有關)
  2. 可作為心因性皮膚發炎 (psychogenic dermatitis) 的合併治療藥物

TSA general feature: 治療攻擊性、吠叫、強迫性行為、亂尿尿等異常行為

48
Q

Clomipramine

A

TSA general feature: 治療攻擊性、吠叫、強迫性行為、亂尿尿等異常行為

Unique feature

  1. TCA中最具選擇性的5-HT reuptake inhibitor
  2. FDA approval: 用於犬的分離焦慮症 (separation anxiety)
  3. 其他用途還有:治療追尾巴行為、口舔致皮膚炎(lick dermatitis)、心因性脫毛(psychogenic alopecia)
  4. 代謝產物desmethylclomipramine:
  • 具更強的antimuscarinic effect
  • Conjugation的過程在 較緩慢, leading to
  • 血中濃度維持較高,因此副作用較強
  • 消化道症狀、散瞳mydriasis、食慾改變等副作用較強 (anti-muscarinic effect)
49
Q

Fluoxetine

A

SSRI (selective serotonin reuptake inhibitors)

Fluoxetine (Prozac® ) 中文名為百憂解,為1980年代後橫掃人醫用抗憂鬱藥物

  1. 要3週後才開始發揮藥效
  2. 安全性極佳,副作用少
  3. 為CYP450的競爭型抑制劑,與TCA或MAO inhibitors一起用可能導致嚴重的serotonin syndrome,因為其會干擾TCA代謝,TCA會被CYP2D6(CYP450的一種)代謝。
50
Q

Sertraline

A

SSRI (selective serotonin reuptake inhibitors)

要3週後才開始發揮藥效

安全性極佳,副作用少

為CYP450的競爭型抑制劑,與TCA或MAO inhibitors一起用可能導致嚴重的serotonin syndrome,因為其會干擾TCA代謝,TCA會被CYP2D6(CYP450的一種)代謝。

51
Q

Paroxetine

A

SSRI (selective serotonin reuptake inhibitors)

要3週後才開始發揮藥效

安全性極佳,副作用少

為CYP450的競爭型抑制劑,與TCA或MAO inhibitors一起用可能導致嚴重的serotonin syndrome,因為其會干擾TCA代謝,TCA會被CYP2D6(CYP450的一種)代謝。

52
Q

Sertraline

A

Sertraline

SSRI (selective serotonin reuptake inhibitors)

要3週後才開始發揮藥效

安全性極佳,副作用少

為CYP450的競爭型抑制劑,與TCA或MAO inhibitors一起用可能導致嚴重的serotonin syndrome,因為其會干擾TCA代謝,TCA會被CYP2D6(CYP450的一種)代謝。

53
Q

serotonin syndrome

A

cause: too much serotonin !!!!! (due to presence fo too much serotonin or unability to remove the serotonin due to MAO inhibitor)
1. MAO inhibitors和以下物質會有很強、危險的藥物之間交互作用 (交感過度興奮)

  • Sympathomimetics
  • 含有tyramine的食物
  • CNS stimulants (caffeine)
  • Reuptake inhibitors (TCA、SSRI)

出現幻覺、昏迷(cognitive)、發抖、發汗、心悸、高血壓、心跳加快(autonomic)、肌肉震顫 (somatic) 可以致死

54
Q

Tyramine

A
  1. Precursor of catecholamines
  2. indirect-acting sympathomimetics:
  3. 類似ephedrine作用,導致NE、EP、DA釋放
  4. 由MAO-A代謝
  5. MAO-A inhibitors和起司一起吃會產生hypertensive crisis血壓飆高
  6. 在啤酒、起司、香蕉、肉、魚、豆類、堅果、巧克力有
55
Q

Selegiline

A
  1. 相對具選擇性的MAO-B inhibitors:影響dopamine (for MAO inhibitor, since side effects are hard to be avoided with a low-specificity, so mostly not being used now. )
  2. 具輕微amphetamine-like特性,會抑制NE和5-HT reuptake
  3. 用途:
    1. Original approval: 治療犬的pituitary-dependent hyperadrenocorticism (DA缺乏導致腦下垂體(pituitary gland)分泌過多ACTH);治療人的Parkinson’s disease
    2. Supplemental approval —治療犬的Cognitive Dysfunction Syndrome (CDS),其類似人的Alzheimer’s disease
    3. 治療progressive irreversible neurodegeneration漸行性不可逆的神經退化【機轉不清楚】
    4. 治療貓的情緒行為異常
    5. 訓練年輕或年長病患的learning
    6. 治療貓的congnitive dysfunction (but not in supplemental approval list)
  4. 要2-3週後才開始發揮藥效
  5. 會產生amphetamine-like的興奮效果
  6. 副作用:除非高劑量,否則副作用很少;包括不安、激動、嘔吐、失去方向感、下痢、嗅覺靈敏度降低等等 (for other MAO, side effects are common!!)
  7. 代謝產物有L –amphetamine (和毒品的D –form不同,其效果弱很多)
  • so it got amphetamine-like stimulant effect
  • Restlessness, agitation, vomiting , disorientation, diarrhea and decreased hearing in dogs
56
Q

L –amphetamine

A
  1. Selegiline代謝產物有L –amphetamine (和毒品的D –form不同,其效果弱很多)
    * so it got amphetamine-like stimulant effect

Restlessness, agitation, vomiting , disorientation, diarrhea and decreased hearing in dogs