Drugs used for Antipsychotics and Mood Stabilization

Question 1

Class: Second-generation (atypical) antipsychotic.
Indications:

Schizophrenia and schizoaffective disorder.
Bipolar disorder (acute manic or mixed episodes and as maintenance therapy).
Irritability associated with autism in children and adolescents.

Mechanism of Action:

Blocks dopamine D2 and serotonin 5-HT2A receptors, reducing both positive and negative symptoms of schizophrenia while also having mood-stabilizing effects.

Side Effects:

Common: most common 2nd gen drug to cause EPS symptoms. Weight gain, sedation, dizziness, and hyperprolactinemia (elevated prolactin levels leading to galactorrhea, gynecomastia, and menstrual irregularities).
Serious: Extrapyramidal symptoms (EPS), especially at higher doses, tardive dyskinesia, and metabolic syndrome (increased blood sugar, cholesterol, and risk of diabetes).

Answer 1

Risperidone (Risperdal)

Question 2

Class: Second-generation (atypical) antipsychotic.
Indications:

Schizophrenia and schizoaffective disorder.
Bipolar disorder (for depressive, manic, and mixed episodes, as well as maintenance therapy).
Adjunctive treatment for major depressive disorder (MDD).
Commonly used as a sedative

Mechanism of Action:

Blocks dopamine D2 and serotonin 5-HT2A receptors, with additional effects on serotonin 5-HT1A and histamine H1 receptors, contributing to its antidepressant and sedative properties.

Side Effects:

Common: Sedation, weight gain, orthostatic hypotension, and dry mouth.
Serious: Metabolic syndrome (increased blood sugar, cholesterol, and risk of diabetes), QT prolongation (risk of arrhythmias), and cataracts with long-term use.

Answer 2

Quetiapine (Seroquel)

Question 3

Class: Second-generation (atypical) antipsychotic.
Indications:

Schizophrenia and schizoaffective disorder.
Bipolar disorder (acute manic or mixed episodes and as maintenance therapy).
Adjunctive treatment for treatment-resistant depression.

Mechanism of Action:

Blocks dopamine D2 and serotonin 5-HT2A receptors, with additional antagonism of histamine H1 and muscarinic receptors, which contribute to its sedative and metabolic side effects.

Side Effects:

Common: Significant weight gain, sedation, dry mouth, and constipation.
Serious: High risk of metabolic syndrome (including significant weight gain, increased blood sugar, and risk of diabetes), hyperlipidemia, and increased risk of cardiovascular events. Also associated with EPS and tardive dyskinesia, though the risk is lower than with first-generation antipsychotics.

Answer 3

Olanzapine (Zyprexa)

Question 4

Class: Second-generation (atypical) antipsychotic.
Indications:

Schizophrenia and schizoaffective disorder.
Bipolar disorder (acute manic or mixed episodes).

Mechanism of Action:

Blocks dopamine D2 and serotonin 5-HT2A receptors, with additional serotonin-norepinephrine reuptake inhibition (SNRIs), which may contribute to its mood-stabilizing effects.

Side Effects:

Common: Drowsiness, nausea, and headache.
Serious: QT prolongation (risk of potentially life-threatening arrhythmias), though lower risk of metabolic side effects like weight gain or diabetes compared to other atypical antipsychotics. Can still cause EPS and tardive dyskinesia, especially at higher doses.

Answer 4

Ziprasidone (Geodon)

Question 5

Class: Second-generation (atypical) antipsychotic, partial dopamine agonist.
Indications:

Primarily lowers prolactin levels which may lead to manic episodes
Schizophrenia and schizoaffective disorder.
Bipolar disorder (acute manic or mixed episodes and as maintenance therapy).
Adjunctive treatment for major depressive disorder (MDD).
Irritability associated with autism.

Mechanism of Action:

Unique mechanism as a partial agonist at dopamine D2 and serotonin 5-HT1A receptors, and an antagonist at serotonin 5-HT2A receptors. This provides antipsychotic effects while reducing the risk of some side effects.

Side Effects:

Common: Insomnia, anxiety, restlessness (akathisia), headache, and gastrointestinal upset.
Serious: Lower risk of metabolic syndrome and weight gain compared to other atypical antipsychotics, but there is still a risk of EPS and tardive dyskinesia. Rarely, may cause compulsive behaviors (e.g., gambling, hypersexuality) due to its partial dopamine agonist activity.

Answer 5

Aripiprazole (Abilify)