Antipsychotics Flashcards
also known as ——- drugs
neuroleptic and anti-schizophrenic drugs.
Psychosis
• Persons experiencing a psychotic episode may have a constellation of symptoms such as disorganized thinking, personality changes, paranoid or delusional beliefs, and hallucinations.
Psychosis has been traditionally linked to the neurotransmitter dopamine. maybe psychosis results from an over activity of dopamine particularly in the mesolimbic pathway.
Hallucinations
defined as sensory perception in the absence of external stimuli. They are different from illusions, which are the misperception of external stimuli.
term psychosis is particularly associated with ———
schizophrenia, bipolar disorder (manic depressive disease) and severe depression.
secondary psychosis
Psychosis arising from non-psychological conditions:
- Neurological disorders
- Electrolyte disorders
- Multiple medical conditions
- Drugs – use, abuse or withdrawal
Neurological disorders associated with psychosis
Brain tumors • Alzheimer's Disease • Multi-infarct dementia • Dementia with Lewy bodies • Multiple sclerosis • Syphilis • Parkinson's Disease • Pick’s disease (robin williams)
Electrolyte disorders associated with psychosis
- Hypo/hyper calcemia
- Hypo/hyper natremia
- Hypokalemia
- Hypo/hyper magnesemia
- Hypophosphatemia
- Hypoglycemia
Medical conditions associated with psychosis
- AIDS
- Lupus
- Lyme Disease
- Sarcoidosis
- Leprosy
- Malaria
Drugs whose use, abuse or withdrawal have been associated with psychosis include:
- OTC drugs such as Dextromethorphan at high doses and antihistamines at high doses
- Atropine
- Antidepressants
- Antiepileptics
- Barbiturates
- Benzodiazepines
- L-dopa
- Narcotic analgesics
- Alcohol
- Amphetamines • Cannabis
- Cocaine
- LSD
- MDMA (ecstasy) • Mescaline
- PCP
- Psilocybin
Neuroleptic drugs
• The neuroleptic or antipsychotic drugs are currently categorized and referred to as being either:
- Typical or first generation neuroleptic
- Atypical or second generation neuroleptic
first generation antipsychotics:
Phenothiazines: Chlorpromazine (Thorazine) Fluphenazine (Prolixin) Perphenazine (Trilafon) Prochlorperazine (Compazine) Thioridazine (Mellaril) Trifluoperazine (Stelazine) Triflupromazine (Vesprin) Levomepromazine (Nozinan)
Thioxanthenes:
Flupenthixol (Depixol)
Thiothixene (Navane)
Zuclopenthixol (Clopixol)
Butyrophenones:
(See note below)
Haloperidol (Haldol)
Droperidol
Atypical antipsychotic medications include
Butyrophenone class: (To further confuse matters, this class of drugs is occasionally listed under the typical antipsychotics as well.
Haloperidol (Haldol)
Droperidol (Inapsine)
Pimozide (Orap) – also indicated for the treatment of Tourette’s syndrome
Melperone
Dibenzodazepine class: Clozapine (Clozaril) Quetiapine fumarate (Seroquel)
Thienobenzodiazepine class:
Olanzapine (Zyprexa)
Benzisoxazole class:
Respiradone (Risperdal)
general Neuroleptic drugs MOA
- The main mechanism of action of both the typical and the atypical neuroleptic drugs is blockade of dopamine receptors in the brain.
- The atypical neuroleptic drugs also serve as antagonists or partial antagonists to serotonin receptors.
- Both typical and atypical neuroleptic drugs may affect various receptor subtypes of norepinephrine, acetylcholine, and histamine as well.
The atypical neuroleptic MOA
these drugs also serve as antagonists or partial antagonists to serotonin receptors.
Both typical and atypical neuroleptic drugs may affect various receptor subtypes of norepinephrine, acetylcholine, and histamine as well.
benefits of atypical neurleptics
considered first line tx now
Two of the defining characteristic of an atypical antipsychotic is the
- decreased propensity of these agents to cause extrapyramidal side effects
- and an absence of sustained prolactin elevation.
** the Blocking D2 receptors in these other pathways is thought to produce many of the unwanted side effects that often accompany the use of the typical antipsychotics.
major dopamine receptor for neuroleptic MOA
• Five dopamine receptors have been identified and the chief antipsychotic effects of the neuroleptics appears related to dopamine blockade at the D2 receptors.
• Excess release of dopamine in the mesolimbic pathway has been linked to psychotic experiences and it is the blockade of dopamine receptors in this pathway that is thought to control psychotic experiences.

typical antipsychotics and dopamine receptors
Typical antipsychotics are relatively non- selective in regards to the mesolimbic pathway and also block dopamine receptors in the mesocortical pathway,
tuberoinfundibular pathway, and the nigrostriatal pathway.
• Blocking D2 receptors in these other pathways is thought to produce many of the unwanted side effects that often accompany the use of the typical antipsychotics.