Antipsychotics are a category of prescription medications within psychiatry used for the treatment of psychosis.

Antipsychotic medications are psychiatric drugs employed in the management of mental illnesses characterized by a disconnect from reality, distortions in perception, impaired thinking abilities, and reduced emotional expression.

These medications are officially approved for addressing specific mental health conditions where psychotic experiences are a prominent feature of the symptom profile.

Antipsychotics, also known as neuroleptics, constitute a class of psychotropic drugs primarily intended to manage psychosis. Schizophrenia is the main target condition, but they are also utilized across a spectrum of psychotic disorders, including manic episodes that present with psychotic symptoms.

Furthermore, antipsychotics are used in conjunction with mood stabilizers in the treatment of bipolar disorder. They also play a role in managing psychosis associated with depressive disorders, bipolar affective disorder, and psychosis linked to Alzheimer’s disease.

Introduction to Psychosis

Psychosis is a term encompassing a range of mental disorders that share one or more of the following key features:

1. Impaired Information Processing: A reduced and distorted capacity to process information accurately and form logical conclusions based on reality.

2. Hallucinations: Sensory experiences occurring in the absence of external stimuli, most frequently auditory (hearing voices) or visual (seeing things), but can also involve tactile (touch) or olfactory (smell) senses.

3. Delusions: Fixed, false beliefs that are firmly held despite contradictory evidence and are not in line with cultural or educational background.

4. Disorganized Thought and Speech: Incoherent speech patterns or a noticeable loosening of associations between thoughts, making communication difficult to follow.

5. Abnormal Motor Behavior: Catatonic behavior (marked decrease in reactivity to the environment or purposeless overactivity) or generally disorganized behavior that is inappropriate or unpredictable.

6. Aggression or Violence: In some cases, psychotic states can be associated with increased agitation, aggression, or violent behavior.

Antipsychotic medications are effective in reducing these symptoms, irrespective of the specific underlying cause or combination of causes of the psychosis.

Conditions frequently associated with psychosis include:

• Schizophrenia

• Mania

• Bipolar disorder

• Schizoaffective disorder

• Severe Depression

• Alcohol withdrawal syndrome

• Delirium

Factors Potentially Contributing to Psychosis:

1. Genetic Predisposition: Inherited genetic factors can increase vulnerability to psychotic disorders.

2. Alcohol Use Disorders: Chronic alcoholism and alcohol withdrawal can induce psychosis.

3. Brain Tumors: Tumors in the brain can sometimes cause psychotic symptoms depending on their location and impact.

4. Traumatic Brain Injuries: Head injuries can, in some instances, lead to the development of psychosis.

5. Central Nervous System Stimulants: Substances that stimulate the central nervous system, such as cocaine, can trigger psychosis.

Psychosis-Inducing Substances

1. Levodopa: A medication used to treat Parkinson’s disease, can paradoxically induce psychosis in some individuals.

2. CNS Stimulants: Stimulant drugs like:

   • Cocaine

   • Amphetamines

   • Khat, cathinone, and methcathinone (psychoactive substances derived from the khat plant)

3. Other Substances:

   • Apomorphine (used in Parkinson’s and erectile dysfunction treatment)

   • Phencyclidine (PCP) – an illicit dissociative drug

Neurotransmitters

Neurotransmitters are chemical messengers in the brain, and can be broadly classified by their primary effect:

1. Excitatory Neurotransmitters: These neurotransmitters stimulate neuronal activity. Examples include:

   • Dopamine

   • Adrenaline (epinephrine)

   • Noradrenaline (norepinephrine)

   • Serotonin (5-HT – 5-hydroxytryptamine)

2. Inhibitory Neurotransmitters: These neurotransmitters reduce neuronal activity. A key example is:

   • Gama Amino Butyric acid (GABA)

SCHIZOPHRENIA

Schizophrenia is a persistent mental illness characterized by disordered thinking and a detachment from reality. It is classified as a psychotic disorder.

In essence, schizophrenia is a mental condition defined by:

• Personality Alterations: Changes in typical personality traits leading to difficulties in interpersonal relationships.

• Mood Disturbance: Disrupted emotional state and regulation.

• Impaired Environmental Perception: Difficulty in accurately understanding and interpreting the surrounding environment.

The onset of schizophrenic symptoms commonly occurs during adolescence or in early adulthood.

It is theorized that schizophrenia is associated with an overactivity of dopamine pathways in the brain. Excessive dopamine release is believed to cause overstimulation of brain cells, resulting in the characteristic abnormal behaviors and experiences of schizophrenia.

DOPAMINE

Dopamine (DA) is a crucial neurotransmitter within the brain.

Effects of Dopamine

Dopamine plays several significant roles in brain function:

• Motor Function: Dopamine is essential for the initiation and modulation of movement.

• Reward and Cognition: It is involved in reinforcement learning, reward pathways, and various cognitive functions, including attention and working memory.

• Prolactin Regulation: Dopamine normally inhibits the release of prolactin, a hormone involved in lactation.

• Emesis (Vomiting): Dopamine pathways play a role in the vomiting reflex.

• Thermoregulation: Dopamine contributes to the regulation of body temperature.

• Appetite Control: Dopamine can influence appetite and food intake.

Signs and Symptoms of Schizophrenia

Schizophrenic symptoms are broadly categorized into two main types:

• Positive Symptoms: These symptoms reflect an excess or distortion of normal functions. They are often described as “psychotic” symptoms.

• Negative Symptoms: These symptoms reflect a deficit or diminution of normal functions. They indicate a reduction in typical emotional and behavioral responses.

Positive and Negative Symptoms of Schizophrenia

Understanding Symptom Balance:

• Positive Symptoms and Stimulation: Positive symptoms are often associated with increased brain activity, particularly in dopamine pathways. Drugs that depress brain activity (like antipsychotics) are used to reduce these symptoms. However, using depressants can potentially worsen negative symptoms.

• Negative Symptoms and Depression (of Function): Negative symptoms are linked to a decrease in certain brain functions, possibly involving serotonin pathways. Historically, attempts to treat negative symptoms with stimulant-like drugs could exacerbate positive symptoms.

The clinical presentation of schizophrenia is highly variable, especially in the relative prominence of positive versus negative symptoms.

Positive symptoms are generally linked to increased activity in dopamine pathways, while negative symptoms are thought to be associated with decreased activity in serotonin pathways and potentially other neurotransmitter systems.