首先要搞明白藥物是怎么起作用的。

The first step is to understand how the drug works.

針對精神病性癥狀（Psychosis）的病理機制有幾個假說，其中一個假說就是多巴胺通路假說。

There are several hypotheses regarding the pathological mechanism of Psychosis, one of which is the dopamine pathway hypothesis.

 

這就要提到多巴胺的四條通路（指多巴胺在體內(nèi)傳播的路徑）：

This will mention the four pathways of dopamine (referring to the way dopamine spreads in the body):

一、中腦邊緣多巴胺通路：

1. Limbic dopamine pathway:

這條通路主要有兩個作用。①產(chǎn)生欣快感（獎賞機制）。②對于當前情境作出快速評估，決策。

This pathway has two main functions. ① Produce euphoria (reward mechanism). ② Make a quick assessment and decision-making for the current situation.

欣快感很好理解，多巴胺是一種大腦分泌的神經(jīng)遞質(zhì)，多巴胺水平高的時候，人會很開心，很興奮，有很多吸毒、物質(zhì)濫用的就是因為這個而上癮，因為這條通路會不斷讓人獲得精神上的|獎賞|。（所以會有那種物質(zhì)濫用誘發(fā)的精神病性癥狀（Drug-induced psychosis)）

Euphoria is well understood. Dopamine is a neurotransmitter secreted by the brain. When the level of dopamine is high, people will be very happy and excited. Many drug users and substance abusers are addicted because of this, because this pathway will continue. Let people get a spiritual |reward|. (So ??there will be that kind of substance abuse induced psychosis (Drug-induced psychosis))

但是，影響欣快感的同時，也會影響到我們的快速決策系統(tǒng)。當多巴胺分泌過多時，我們的決策系統(tǒng)會變得異?；钴S，簡單來說就是會變得過度敏感、過度反應。這就是常見的精神病性癥狀 - 妄想、幻覺產(chǎn)生的基礎。

However, while affecting euphoria, it also affects our rapid decision-making system. When dopamine is secreted too much, our decision-making system will become abnormally active. Simply put, it will become over-sensitive and over-reacting. This is the basis for common psychotic symptoms-delusions and hallucinations.

比如，本來簡單的和他人的目光接觸，演變?yōu)?ldquo;他為什么要盯著我看？他是不是想害我？“”剛才那個路人碰了我一下，他是不是借此在我飯菜里下毒？”由此產(chǎn)生的妄想、幻覺，也就是精神病性癥狀中常提到的陽性癥狀（Positive Symptoms）。

For example, the original simple eye contact with others has evolved into "Why is he staring at me? Is he trying to harm me?" The passerby just touched me, did he use it to poison my food? ?" The resulting delusions and hallucinations are the positive symptoms (Positive Symptoms) often mentioned in psychotic symptoms.

目前抗精神病藥物的主要邏輯，就是阻滯多巴胺受體，受體接受不到多巴胺了，那么就相當于多巴胺的活躍度下降，給原本過于活躍的中腦邊緣多巴胺通路[降降溫]。

At present, the main logic of antipsychotic drugs is to block dopamine receptors, and the receptors cannot accept dopamine, then it is equivalent to a decrease in dopamine activity, and to the originally overactive midbrain limbic dopamine pathway [cooling down].

二、中腦皮質(zhì)多巴胺通路：

2. Midbrain cortex dopamine pathway:

這一條通路主要和大腦的前額葉相關。前額葉在大腦結構中承擔著相對高級的功能，包括認知、思考、動力、社交。和大腦的其他區(qū)域不同，前額葉顯得相對“高級”。與之相反，比如，腦干主要是影響呼吸、影響心跳，這都是一個生物為了活著，發(fā)展出的相對基本、低級的功能，而高度發(fā)展的前額葉是[人之所以為人，區(qū)別于其他生物]的一個很大原因，因此其重要性可想而知。

This pathway is mainly related to the prefrontal lobe of the brain. The prefrontal lobe bears relatively high-level functions in the brain structure, including cognition, thinking, motivation, and social interaction. Unlike other areas of the brain, the prefrontal lobe appears relatively "advanced." On the contrary, for example, the brain stem mainly affects breathing and heartbeat. This is a relatively basic and low-level function developed by a creature in order to live, and the highly developed prefrontal lobe is [the reason why people are humans is different from other Biology] is a big reason, so its importance can be imagined.

在精神病性癥狀中，這一條與前額葉相關的多巴胺通路，恰恰不那么活躍，體現(xiàn)出機能的衰弱。因此造成的表現(xiàn)是，認知功能受損，社交功能退化。也就是常說的，陰性癥狀（Negative Symptoms）。

In psychotic symptoms, this dopamine pathway related to the prefrontal lobe is just not so active, reflecting the weakness of the function. The resulting performance is impaired cognitive function and degraded social function. That is to say, negative symptoms (Negative Symptoms).

補充說明：陰性癥狀：指人們似乎對周圍的世界感到孤立，對日常的社會交往不感興趣，而且經(jīng)常表現(xiàn)得沒有感情和平淡

Supplementary note: Negative symptoms: People seem to feel isolated from the world around them, are not interested in daily social interactions, and often show no emotion and flatness

藥物的副作用（藥物的作用機制是讓多巴胺受體阻滯，接收不到多巴胺），可能會加重陰性癥狀。不過這種副作用已經(jīng)在非典型抗精神病藥物（新一代）中得以改善，非典型抗精神病藥物可以在降溫中腦邊緣多巴胺通路的同時（即減輕陽性癥狀），增加中腦皮質(zhì)多巴胺通路的活性（減輕陰性癥狀）。

The side effects of the drug (the mechanism of action of the drug is to block the dopamine receptors and not receive dopamine), which may aggravate the negative symptoms. However, this side effect has been improved in atypical antipsychotics (new generation). Atypical antipsychotics can reduce the temperature of the limbic dopamine pathway (that is, reduce the positive symptoms) and increase the activity of the dopamine pathway in the midbrain cortex ( Alleviate negative symptoms).

三、黑質(zhì)紋狀體多巴胺通路：

3. Dopamine pathway in substantia nigra striatum:

這條通路是錐體外系神經(jīng)系統(tǒng)的一部分，控制著運動神經(jīng)，如果有問題可能會產(chǎn)生帕金森病。這條通路的過度活躍，可能會產(chǎn)生運動機能亢進（比如舞蹈癥、局部抽搐）。

This pathway is part of the extrapyramidal nervous system and controls the motor nerves. If there is a problem, Parkinson's disease may occur. Overactivity of this pathway may cause hyperkinesis (such as chorea, local convulsions).

精神分裂癥患者的這條通路本身沒有大問題。但是由于抗精神病藥物是專注于多巴胺的，我們很難控制多巴胺在具體某個通路上的活動如何，所以當給藥時，影響到通路一，就會影響到通路二、三、四。也就產(chǎn)生了，抗精神病藥物的常見副作用：

There is no major problem with this pathway for schizophrenic patients. However, since antipsychotic drugs are focused on dopamine, it is difficult for us to control how dopamine is active in a specific pathway. Therefore, when the drug is administered, it affects pathway one, and will affect pathway two, three, and four. This also resulted in the common side effects of antipsychotic drugs:

①靜坐不能（Akathisia):表現(xiàn)為煩躁不安，不能靜坐或靜臥，反復走動或原地踏步走，可伴有不自主運動。

①Akathisia: manifested as irritability, inability to sit or lie still, walk around repeatedly or walk in place, which may be accompanied by involuntary movement.

②急性肌張力不全：表現(xiàn)為眼、面、口、頸等局部性肌痙攣所致的怪異表現(xiàn)。

②Acute dystonia: manifested as strange manifestations caused by local muscle spasms of the eyes, face, mouth, and neck.

四、結節(jié)漏斗多巴胺通路：

4. Nodular funnel dopamine pathway:

從下丘腦發(fā)出投射到垂體前葉，影響催乳素的分泌。

Projections from the hypothalamus to the anterior pituitary gland affect the secretion of prolactin.

精神分裂癥患者這一條通路本身沒有大問題。只是藥物的副作用對這條通路有所影響。多巴胺受體 D2 被阻滯后，會引起催乳素升高，引起泌乳現(xiàn)象（即使未懷孕），月經(jīng)紊亂等。確實在病房里，經(jīng)常會看到，剛進來比較瘦弱的女孩子，吃藥吃了一個多月之后，體重明顯上升,這種現(xiàn)象比較常見。

There is no major problem with this pathway in schizophrenia. It's just the side effects of the drug that affect this pathway. The delayed dopamine receptor D2 will cause the increase of prolactin, cause lactation (even if not pregnant), menstrual disorders, etc. Indeed, in the ward, one often sees that a relatively thin girl who has just come in has a significant increase in weight after taking medicine for more than a month. This phenomenon is more common.

to sum up:

本文介紹了一些常見的抗精神病藥物（Antipsychotics)的副作用，包括：錐體外系癥狀（靜坐不能、急性肌張力不全等）、引發(fā)泌乳，月經(jīng)紊亂等。其余的副作用通常還包括體重增加

、口干、便秘等。

This article introduces the side effects of some common antipsychotics, including: extrapyramidal symptoms (akathisia, acute dystonia, etc.), lactation, menstrual disorders, etc. Other side effects usually include weight gain

, dry mouth, constipation, etc.

副作用這么多，我該怎么選擇？

With so many side effects, how should I choose?

總的來說，醫(yī)生會根據(jù)你的情況，幫你匹配合適的藥物，這通常需要一些“試驗”和耐心。不是副作用越小就越好，雖然副作用小，但這藥可能對你也沒有用。而且不是所有的副作用對每個人來說都同等重要。比如，一個肝功能代謝本來就不太好的人，可能不適合藥物 A（藥物 A 對肝臟的影響更大，但療效更好），更適合藥物 B；而另一個沒有代謝問題的人，可能就適合藥物 A 多一些（但是肝臟負擔重一些）。副作用只是我們選擇藥物時考慮的其中一個維度。

In general, the doctor will help you match the right medicine according to your situation, which usually requires some "testing" and patience. It’s not that the smaller the side effects, the better. Although the side effects are small, the medicine may not be useful for you. And not all side effects are equally important to everyone. For example, a person with poor liver function metabolism may not be suitable for drug A (drug A has a greater impact on the liver, but the effect is better), and is more suitable for drug B; while another person without metabolic problems may It is more suitable for drug A (but heavier burden on the liver). Side effects are just one of the dimensions we consider when choosing drugs.