Legend:
- pKi ~X.X: Affinity with a pKi value of approximately X.X.
- (PA): The medication acts as a Partial Agonist at the receptor.
- (Ag): The medication acts as an Agonist at the receptor.
- <5: pKi value less than 5, indicating very low or negligible affinity.
- –: No available or relevant data.
- Notes: Important information about the medication's action or special properties.
Explanation of Receptors:
- Dopamine Receptors (D₂, D₃, D₄):
- D₂, D₃, D₄: Targets for antipsychotic effects; blockade can lead to extrapyramidal symptoms (EPS).
- Serotonin Receptors (5-HT):
- 5-HT₁A: Agonism or partial agonism can provide anxiolytic and antidepressant effects.
- 5-HT₂A: Blockade enhances antipsychotic effects and reduces EPS.
- 5-HT₂C: Involved in weight gain and metabolic effects.
- 5-HT₇: Influences cognition and mood; blockade may improve cognitive symptoms.
- Muscarinic Acetylcholine Receptors (M1, M4):
- M1: Blockade can lead to anticholinergic side effects (e.g., dry mouth).
- KarXT: Acts as an agonist at M1/M4 receptors.
- Histamine H₁ Receptors:
- Blockade leads to sedation and weight gain.
- Alpha-1 Adrenergic Receptors:
- Blockade can cause orthostatic hypotension (dizziness upon standing).
- Sigma-1 Receptors:
- Involved in neuroprotection and neurotransmission; binding may influence antipsychotic effects.
Important Notes:
- Data Variability: Exact pKi values may vary depending on the study and measurement methods. The values provided are approximations.
- Clinical Relevance: A medication's effect depends not only on its affinity for a receptor but also on factors like intrinsic activity, pharmacokinetics, and individual patient factors.
- Personalized Therapy: The choice of an appropriate antipsychotic should be individualized based on symptoms, side effects, and patient needs.
Sources:
- PDSP Ki Database (Psychoactive Drug Screening Program, University of North Carolina)
- Current scientific literature and pharmacological databases
- Textbooks of Pharmacology and Psychopharmacology
Final Note:
This table is intended for informational purposes and provides an overview of the various mechanisms of action of antipsychotics. It does not replace professional medical advice. For questions regarding therapy or medication selection, please consult a healthcare professional.
Explanations of the individual medications:
Aripiprazole
- Mechanism of Action: Aripiprazole acts as a partial agonist at dopamine D₂ and D₃ receptors and at serotonin 5-HT₁A receptors, while antagonizing serotonin 5-HT₂A receptors. This unique mechanism allows it to modulate both overactivity and underactivity of the dopamine system.
- Indications: Used for the treatment of schizophrenia, bipolar disorder, and as an adjunctive therapy in major depressive disorder.
- Side Effects: Common side effects include akathisia (inner restlessness), nausea, headache, and insomnia. It has a lower risk of extrapyramidal symptoms (EPS) and metabolic side effects compared to other antipsychotics.
Brexpiprazole
- Mechanism of Action: Similar to aripiprazole, brexpiprazole is a partial agonist at D₂ and 5-HT₁A receptors and an antagonist at 5-HT₂A receptors. It has a higher affinity for 5-HT₂A receptors.
- Indications: Used to treat schizophrenia and as an adjunctive therapy in major depressive disorder.
- Side Effects: May cause weight gain, drowsiness, and akathisia. It has a favorable side effect profile with a low risk of EPS.
Cariprazine
- Mechanism of Action: Acts as a partial agonist at D₂ and D₃ receptors, with a particularly high affinity for the D₃ receptor, which may contribute to the improvement of negative symptoms.
- Indications: Treatment of schizophrenia and bipolar disorder, including manic and mixed episodes.
- Side Effects: Common side effects include akathisia, nausea, and dizziness. Monitoring for EPS is important.
Risperidone
- Mechanism of Action: Acts as an antagonist at D₂ and 5-HT₂A receptors, as well as alpha-1 adrenergic and histamine H₁ receptors.
- Indications: Used for schizophrenia, bipolar disorder, and behavioral disorders in dementia.
- Side Effects: EPS at higher doses, weight gain, sedation, and hyperprolactinemia (elevated prolactin levels).
Paliperidone
- Mechanism of Action: The primary active metabolite of risperidone; acts as an antagonist at D₂ and 5-HT₂A receptors.
- Indications: Treatment of schizophrenia and schizoaffective disorder.
- Side Effects: Similar to risperidone, including EPS, weight gain, and hyperprolactinemia.
Olanzapine
- Mechanism of Action: Blocks D₂, 5-HT₂A, histamine H₁, muscarinic M1, and alpha-1 adrenergic receptors.
- Indications: Treatment of schizophrenia and bipolar disorder (manic and depressive episodes).
- Side Effects: Weight gain, sedation, anticholinergic effects (e.g., dry mouth, constipation), increased risk of metabolic syndrome and type 2 diabetes mellitus.
Quetiapine
- Mechanism of Action: Acts as an antagonist at D₂ and 5-HT₂A receptors, with high affinity for histamine H₁ and alpha-1 adrenergic receptors. Its metabolite norquetiapine inhibits norepinephrine reuptake.
- Indications: Treatment of schizophrenia, bipolar disorder, and as an adjunctive therapy in major depressive disorder.
- Side Effects: Sedation, weight gain, orthostatic hypotension. Low risk of EPS.
Clozapine
- Mechanism of Action: Blocks D₂, D₄, 5-HT₂A, muscarinic M1, histamine H₁, and alpha-1 adrenergic receptors.
- Indications: Effective in treatment-resistant schizophrenia and reduces suicidal ideation.
- Side Effects: Risk of agranulocytosis (requires regular blood monitoring), sedation, hypersalivation, weight gain, increased risk of seizures and metabolic syndrome.
Haloperidol
- Mechanism of Action: A potent antagonist at D₂ receptors with low affinity for other receptors.
- Indications: Treatment of acute psychosis, schizophrenia, and manic episodes.
- Side Effects: High risk of EPS (e.g., parkinsonism, akathisia), hyperprolactinemia, low risk of sedation and anticholinergic effects.
Lurasidone
- Mechanism of Action: Acts as an antagonist at D₂ and 5-HT₂A receptors, a partial agonist at 5-HT₁A receptors, and an antagonist at 5-HT₇ receptors.
- Indications: Treatment of schizophrenia and depressive episodes associated with bipolar disorder.
- Side Effects: Akathisia, insomnia, nausea. Low risk of metabolic side effects.
Amisulpride
- Mechanism of Action: A selective antagonist at D₂ and D₃ receptors. At low doses, it increases dopamine release by blocking presynaptic autoreceptors.
- Indications: Effective for negative symptoms of schizophrenia.
- Side Effects: EPS at higher doses, hyperprolactinemia, low risk of weight gain.
Ziprasidone
- Mechanism of Action: Acts as an antagonist at D₂ and 5-HT₂A receptors, an agonist at 5-HT₁A receptors, and inhibits the reuptake of serotonin and norepinephrine.
- Indications: Treatment of schizophrenia and manic or mixed episodes in bipolar disorder.
- Side Effects: Risk of QT interval prolongation (requires ECG monitoring), sedation, low risk of weight gain.
Sertindole
- Mechanism of Action: Acts as an antagonist at D₂, 5-HT₂A, and alpha-1 adrenergic receptors.
- Indications: Treatment of schizophrenia, but less commonly used due to cardiac risks.
- Side Effects: QT prolongation (increased risk of arrhythmias), weight gain, dizziness.
Flupentixol
- Mechanism of Action: Acts as an antagonist at D₂ receptors, also affects 5-HT₂A, histamine H₁, and alpha-1 adrenergic receptors.
- Indications: Treatment of schizophrenia and other psychotic disorders; may have activating properties.
- Side Effects: EPS, insomnia, restlessness, sedation, orthostatic hypotension.
KarXT
- Mechanism of Action: A combination of xanomeline (an M1/M4 muscarinic receptor agonist) and trospium (a peripheral muscarinic receptor antagonist). It aims to activate central muscarinic receptors while minimizing peripheral side effects.
- Indications: Under development for the treatment of schizophrenia, particularly to improve cognitive and negative symptoms.
- Side Effects: Early studies show reduced anticholinergic side effects due to the combination with trospium.
Note: These explanations are intended for informational purposes only and do not replace professional medical advice. If you have health-related questions or concerns, please consult your physician or a qualified healthcare professional.
Zuletzt bearbeitet:
