antipsychotic drugs

1. NEUROLEPTICS=
ANTIPSYCHOTICS

2. DEFINITION
• Neuroleptics, also known as antipsychotic medications, are
used to treat and manage symptoms of many psychiatric
disorders.
• They are a class of medication primarily used to manage
psychosis (including delusions, hallucinations, paranoia or
disordered thought), principally in schizophrenia but also in a
range of other psychotic disorders.
• They are also the mainstay together with mood stabilizers in
the treatment of bipolar disorder.

3. ANTIPSYCHOTIC DRUGS
Antipsychotic drugs are used primarily to
treat schizophrenia (a biologic illness), but
they are also effective in other psychotic
states, including manic states with psychotic
symptoms such as grandiosity, paranoia,
and hallucinations, and delusions.
Antipsychotic drugs are not curative and do
not eliminate the chronic thought disorder,
but they often decrease the intensity of
hallucinations and delusions and permit the
person with schizophrenia to function in a
supportive environment.

4. CO M PA R I N G P S YC H O S I S
A N D P S YC H OT I C D I S O R D E R S
• Psychosis is NOT the same as psychotic
disorders.
• Psychosis is a symptom of several mental
health disorders, including psychotic
disorders. It can occur in conditions that
are not psychotic disorders.
• For example, people with alcohol
addiction can develop symptoms of
psychosis even though alcoholism isn’t a
psychotic disorder. Brain tumors and
stroke can also result in psychosis.
• Psychosis is a break from reality
characterized by delusions, hallucinations
and disorganized speech and behavior.
• Medical professionals refer to the onset
of a psychotic episode as a psychotic
break.

5. T Y P E S O F P S YC H OT I C
D I S O R D E R S
People with psychotic disorders can
experience a range of symptoms, including
paranoia and suicidal thoughts. They have
an impaired relationship with reality and
may hear or see things that do not exist.
Psychotic disorders can be short- or long-
term conditions. People can experience a
single psychotic episode triggered by
extreme stress or other temporary
changes to the brain. They can also deal
with multiple psychotic breaks.
Many types of psychotic disorders exist.
Schizophrenia is the most common type of
psychotic disorder and is one of the
leading causes of disability worldwide. But
other types of psychotic conditions can
also create significant health problems.

6. CAUSES OF PSYCHOTIC DISORDERS
Psychosis and psychotic disorders are typically
caused by chemical changes in the brain. Trauma
can trigger the onset of psychotic conditions, but it
is rarely considered to be the sole cause.
Acute stress can provoke a psychotic break,
especially when it occurs alongside a medical
condition or substance abuse. But unless a person
has an underlying disorder, these episodes quickly
resolve and rarely recur. Psychotic episodes
triggered by substance use and stress rarely develop
into chronic conditions like schizophrenia.

7. SCHIZOPHRENIA
• Schizophrenia is a psychosis, a type of mental illness characterized by distortions in
thinking, perception, emotions, language, sense of self, and behavior
• Someone diagnosed with schizophrenia may lose their sense of reality and have
bizarre and abnormal behaviors.
• Schizophrenia comprises positive and negative symptoms.

8. SCHIZOPHRENIA
Positive symptoms add abnormal cognitive or perceptual experiences
and are the symptoms most commonly associated with schizophrenia,
including:
• Hallucinations
• Delusions
• Disorganized speech
• Disordered movement
Negative symptoms are those that subtract something that
psychiatrically stable people normally experience or do. For example,
while schizophrenia can manifest through rambling, excessive speech,
it can also take form in silence.
Negative symptoms of schizophrenia include:
• Flat affect (reduced emotional expression)
• Social withdrawal (loss of interest in social activities)
• Anhedonia (reduction or loss of ability to experience pleasure)
• Avolition (reduced motivation or inability to sustain normal

11. PHARMACOKINETICS
Absorption and Distribution
• Most antipsychotics are readily but incompletely absorbed.
• Significant first-pass metabolism.
• Bioavailability is 25-65%.
• Most are highly lipid soluble.
• Most are highly protein bound (92-98%).
• High volumes of distribution (>7 L/Kg).
• Slow elimination.
• Duration of action longer than expected, metabolites are present and relapse occurs, weeks after discontinuation
of drug!

12. PHARMACOKINETICS
Metabolism
• Most antipsychotics are almost completely metabolized
• Most have active metabolites, although not important in
therapeutic effect

13. PHARMACOKINETICS
Excretion
• Antipsychotics are almost completely metabolized
and thus, very little is eliminated unchanged.
• Elimination half-lives are 10-24 hrs.

14. ADMINISTRATION
• Most first-generation antipsychotic medications are available in oral formulations.
• Several are also available in injectable intramuscular formulations, which are useful in
the treatment of psychotic agitation.
• Clinicians sometimes use intravenous formulations of haloperidol and droperidol to
treat psychosis, agitation, or delirium in acute medical settings.
• Second-generation antipsychotics are available in oral form.
• The injectable form is for use in older and non-complaint patients, so the steady dose
of the antipsychotic is available without any withdrawal effects.

16. There are important differences
regarding adverse effects
profiles.
First generation antipsychotics
are associated with higher risk
of neurological side effects.
On the other hand, second-
generation antipsychotics
gained popularity thanks to a
lower risk of neurological side
effects. Later, it was discovered
that these drugs are associated
with an increased risk of
developing metabolic side
effects: hyperglycemia, weight
gain and dyslipidemia.

17. ADVERSE EFFECTS

18. DRUG INTERACTIONS
• Pharmacokinetic interactions occur when the combination of drugs results in alterations in
the absorption, distribution, metabolism or excretion of either agent.
• As a group, the antipsychotics are highly protein bound (>90%) and distribute widely into
tissues.
• As a consequence, interactions can arise from combining antipsychotics with other agents
that are also highly protein bound.
• Antipsychotics undergo phase I and II metabolism to more water-soluble compounds to aid
in excretion from the body.
• Most antipsychotics are metabolised by the CYP system and potential drug interactions
could occur when they are administered with other agents that affect or are metabolised by
the same isozymes.

19. DRUG INTERACTIONS
Additive effects with:
• sedatives.
• anticholinergics.
• antihistaminergics.
• alpha-AR blocking drugs.
• drugs with quinidine-like action (thioridazine).

20. DISCONTINUATION
• Physicians recommend a gradual withdrawal when discontinuing antipsychotics to
avoid acute withdrawal syndrome or rapid relapse.
• Symptoms of withdrawal commonly include nausea, vomiting, and loss of
appetite.Other symptoms may include restlessness, increased sweating, and trouble
sleeping
• Less commonly there may be a feeling of the world spinning, numbness, or muscle
pains. Symptoms generally resolve after a short period of time.
• There is tentative evidence that discontinuation of antipsychotics can result in
psychosis. It may also result in recurrence of the condition that is being treated.
• Withdrawal effects may also occur when switching a person from one antipsychotic to
another

21. SOURCES
• https://psychopharmacologyinstitute.com/publication/first-vs-second-generation-
antipsychotics-2082
• http://lotuseat3r.blogspot.com/2014/04/first-generation-and-second-generation.html
• https://link.springer.com/article/10.2165/00023210-199809050-00005
• https://www.therecoveryvillage.com/mental-health/psychosis/
• https://psychopharmacologyinstitute.com/publication/mechanism-of-action-of-
antipsychotic-agents-2094
• https://www.ncbi.nlm.nih.gov/books/NBK459150/
• https://en.wikipedia.org/wiki/Antipsychotic#Adverse_effects

22. THANK YOU!
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