Psychopharmacology and Other Biologic Treatments - PowerPoint PPT Presentation


PPT – Psychopharmacology and Other Biologic Treatments PowerPoint presentation | free to download - id: ef96f-ZDc1Z


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation

Psychopharmacology and Other Biologic Treatments


Subspecialty of pharmacology that includes medications affecting the brain and ... Parkinsonism: rigidity, akinesia (slow movement), and tremor, masklike face, ... – PowerPoint PPT presentation

Number of Views:59
Avg rating:3.0/5.0
Slides: 50
Provided by: maryan3


Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Psychopharmacology and Other Biologic Treatments

Psychopharmacology and Other Biologic Treatments
  • Chapter 8

  • Subspecialty of pharmacology that includes
    medications affecting the brain and behavior used
    to treat mental disorders including
  • antipsychotics
  • mood stabilizers
  • antidepressants
  • antianxiety medications
  • stimulants
  • Provides a basis for understanding specific
    biologic treatments of psychiatric disorders

Pharamacodynamics Where Drugs Act
  • Four sites of action
  • Receptors (those sites to which a
    neurotransmitter can specifically adhere to
    produce a change in the cell membranes)
  • Ion channels
  • Enzymes
  • Carrier Proteins
  • Biologic action depends on how its structure
    interacts with a receptor.

  • Types of Action
  • Agonist same biologic actin
  • Antagonist opposite effect
  • Interactions with a receptor
  • Selectivity specific for a receptor
  • Affinity degree of attraction
  • Intrinsic activity ability to produce a
    biologic response once it is attached to receptor

Ion Channels
  • Drugs can block or open the ion channels
  • Example benzodiazepine drugs facilitate GABA in
    opening the chloride ion channel

  • Enzymes catalyze specific biochemical reactions
    within cells and are targets for some drugs.
  • Monoamine oxidase is an enzyme that breaks down
    most bioamine neurotransmitters (NE, DA, 5-HT).
  • Enzymes may be inhibited to produce greater
    neurotransmitter effect.

Carrier Proteins
  • Transport neurotransmitters across cell membranes
  • Medications may block or inhibit this transport.
  • Example antidepressants

Efficacy and Potency
  • Efficacy - Ability of a drug to produce a
    response as a result of the receptor or receptors
    being occupied.
  • Potency - Dose required to produce the desired
    biologic response.
  • Loss of effect
  • desensitization (rapid decrease in drug effect)
  • tolerance (gradual decrease in the effect of a
    drug at a given dose)
  • can lead to being treatment refractory

Target Symptoms and Side Effects
  • Target symptoms
  • Specific symptoms for each class of medication
  • No drug attacks such a target symptom
  • Side effects - Responses not related to target
    symptoms (Table 8.1, 8.1).
  • Adverse effects Unwanted effects with serious
    physiologic consequences.

Drug Toxicity
  • Toxicity Point at which concentrations of the
    drug in the blood stream become harmful or
    poisonous to the body.
  • Therapeutic index Ratio of the maximum nontoxic
    dose to the minimum effective dose.
  • High therapeutic index Wide range between dose
    at which the rug begins to take effect and dose
    that would be considered toxic.
  • Low therapeutic index - low range

  • From site of administration into the plasma
  • Oral - (tablet and liquid) (Table 8-3)
  • Most Convenient
  • Most variable (food and antacids)
  • First pass effect
  • Decreased Gastric Motility (age, disease,
  • IM - Short-and long acting
  • IV - Rarely used

Pharmacokinetics How the Body Acts on the Drug
  • Absorption
  • Distribution
  • Metabolism
  • Elimination

  • Amount of drug that reaches systemic circulation
  • Often used to compare one drug to another,
    usually the higher the bioavailability, the

  • Amount of drug found in various tissues,
    especially the intended ones.
  • Psychiatric drugs must pass through blood-brain
    barrier (most fat-soluble)
  • Factors effecting distribution
  • Size of organ ( larger requires more)
  • Blood flow ( more, greater concentration)
  • Solubility (greater, more concentration)
  • Plasma Protein (if bound, slower distribution,
    stays in body longer
  • Anatomic Barriers (tissues surrounding)

Crossing the Blood Brain Barrier
  • Passive diffusion
  • Drug must dissolve in the structure of the cell
  • Lipid solubility is necessary for drugs passing
    through blood brain barrier (then, can also pass
    through placenta)
  • Binding to other molecules
  • Plasma protein binding
  • The more protein binding, the less drug activity.
  • Can bind to other cells, especially fat cells.
    Then are released when blood level decreases.

  • Process by which the drug is altered and broken
    down into smaller substances (metabolites) that
    are usually inactive.
  • Lipid-soluble drugs become more water soluble, so
    they may be more readily excreted.
  • Most metablism is carried out in the liver.

Cytochrome P450
  • Many process carried out by enzyme class
    Cytochrome P-450
  • high affinity for fat-soluble drugs
  • involved in metabolism of most psychiatric
  • Example SSRIs inhibitors of the subfamily

  • Clearance Total amount of blood, serum, or
    plasma from which a drug is completely removed
    per unit time.
  • Half-life Time required for plasma
    concentrations of the drug to be reduced by 50.
  • Only a few drugs eliminated by kidneys (lithium)
  • Most excreted in the liver
  • excreted in the bile and delivered to the
  • may be reabsorbed in intestine and re-circulate
    (up to 20)

Dosing and Steady State
  • Dosing Administration of medication over time,
    so that therapeutic levels can be achieved.
  • Steady-state
  • drug accumulates and plateaus at a particular
  • rate of accumulation determined by half life
  • reach steady state in about five times the
    elimination half-life

Pharmacokinetics Cultural Considerations
  • 9 of whites - genetically defective P-4502D6
  • Asian descent
  • Metabolize ethanol to produce higher
    concentrations of acetaldehyde (flushing,
  • Require 1/2 to 1/3 dose antipsychotics and more
    severe side effects
  • Cardiovascular effects of propranolol
  • Asian descent - more sensitive
  • African descent - less sensitive

Phases of Drug Treatment
  • Initiation
  • Stabilization
  • Maintenance
  • Discontinuation

Psychiatric Medications
  • Antipsychotic Medications
  • Movement Disorders Medication
  • Mood Stabilizers
  • Antimania
  • Antidepressants
  • Antianxiety and Sedative-Hypnotic
  • Stimulants

Antipsychotic Medications
  • Target symptoms psychosis
  • Types
  • Conventional
  • Atypical
  • Absorption variable
  • clinical effects seen 30-60 min
  • IM less variable (avoid 1st pass)
  • when immobile, less absorption
  • Metabolism liver
  • Excretion slow
  • accumulates in fatty tissues
  • 1/2 life of 24 hours or more

Antipsychotic Medications
  • Target symptoms psychosis
  • Types
  • Conventional
  • Atypical
  • Absorption variable
  • clinical effects seen 30-60 min
  • IM less variable (avoid 1st pass)
  • when immobile, less absorption
  • Metabolism liver
  • Excretion slow
  • accumulates in fatty tissues
  • 1/2 life of 24 hours or more

Antipsychotic Medications (cont..)
  • Preparations
  • Oral
  • IM
  • Depot - haloperidol and fluphenazine
  • Side Effects
  • Cardiovascular - orthostatic Hypertension
  • Weight-gain blocking histamine receptor
  • Endocrine and sexual block dopamine, interfere
    with prolactin
  • Blood Dyscrasias - agranulocytosis

Antipsychotic Medications
  • Conventional
  • Phenothiazines (Thorazine, Prolixin)
  • Thioxanthenes (Navane)
  • Dibenzoxazepines (Loxitane)
  • Haloperidol (Haldol)
  • Atypical or Novel
  • Clozapine (Clozaril)
  • Risperidone (Risperdal)
  • Olanzapine (Zyprexa)
  • Quetiapine (Seroquel)
  • Ziprasidone (Geodon)

Antipsychotic Side Effects
  • Cardiovasular
  • Anticholinergic
  • Weight Gain
  • Endocrine and Side Effects
  • Blood Disorders
  • Miscellaneous

Medication-Related Movement Disorders Acute
  • Can occur in 90 of all patients
  • Dystonia involuntary muscle spasms, abnormal
    postures, oculogyric crisis, torticollis
  • Parkinsonism rigidity, akinesia (slow movement),
    and tremor, masklike face, loss of spontaneous
  • Akathisia Inability to sit still, restlessness

Movement Disorders Acute (cont.)
  • Etiology (acute)
  • Related to dopamine in nigrostrial pathway that
    increases cholinergic activity
  • Treatment
  • Anticholinergic Medication for dystonia,
    parkinsonism (Artane and Cogentin)
  • Akathisia does not usually respond to
    anticholinergic medication. Beta blockers have
    best success.

Movement Disorders Chronic
  • Tardive Dyskinesia
  • Irregular, repetitive involuntary movements of
    mouth, face, and tongue, including chewing,
    tongue protrusion, lip smacking, puckering of the
    lips, and rapid eye blinking. Abnormal finger
    movements are common.
  • Symptoms
  • Begin after 6 months, but also as antipsychotics
    are withdrawn
  • Irreversible - controversy

Movement Disorders Chronic
  • Etiology
  • believed that chronic dopamine suppression in the
    EPS causes an overactivation of the system
  • increases in antipsychotic meds, suppresses
  • Treatment
  • prevention by using lowest possible dosage,
    minimize use of PRN, closely monitor individuals
    in high-risk groups
  • monitoring tools

Mood Stabilizers Antimania Lithium Carbonate
  • Action uncertain, crosses cell membranes,
    altering sodium transport, not protein bound
  • Side Effects thirst, metallic taste, increased
    frequency or urination, fine head and hand
    tremor, drowsiness, and mild diarrhea
  • Blood levels monitored (lithium toxicity - severe
    diarrhea, vomiting, drowsiness, muscular
    weakness, and lack of coordination, withhold)

Lithium Carbonate
  • Monitor creatinine concentrations, thyroid
    hormones, and CBC every 6 months.
  • Kidney damage may be a risk.
  • Thyroid function may be altered usually after
    6-18 months. Observe for dry skin, constipation,
    bradycardia, hair loss, cold intolerance.
  • Avoid during pregnancy.

Mood Stabilizers Antimania Anticonvulsants
  • Valporate and derivatives (divalproex sodium -
  • Carbamazapine (Tegretol)
  • Gabapentin (Neurontin) (least side effects)
  • Lamotrigine (Lamictal)
  • Topiramate (Topamax)
  • Highly protein bound
  • Metabolized by the cytochrome P-540 system
  • Side effects dizziness, drowsiness, tremor,
    visual disturbance, nausea, vomiting

Anticonvulsant Mood Stabilizers
  • Only carbamazepine is approved for mania.
  • Used when patients have not responded to lithium
  • Pharmacokinetics
  • Highly protein bound, metabolized by P450 system
    (potential drug-drug interaction)

Carbamazepine Side Effects
  • Dizziness, drowsiness, tremor, visual
    disturbances, nausea, and vomiting
  • Minimized by treating in low doses
  • Give with food
  • Weight gain
  • Alopecia (hair loss)

Antidepressants Table 8.11,12 Tricyclic
Tertiary Amines
  • Amitriptyline (Elavil)
  • Clomipramine (Anafranil)
  • Doxepine (Sinequan)
  • Imipramine (Tofranil)
  • Trimipramine (Surmontil)

Antidepressants Secondary Amines
  • Amoxapine (Asendin)
  • Desipramine (Norpramin)
  • Nortriptyline (Aventyl, Pamelor)
  • Protrypyline (Vivactil)

Side Effects -- TCAs
  • Most common uncomfortable side effects
  • sedation
  • orthostatic hypotension
  • anticholinergic
  • Others
  • tremors,
  • restlessness, insomnia, confusion
  • pedal edema, headache, and seizures
  • Blood dyscrasias
  • Sexual dysfunction
  • Adverse
  • cardiotoxicity

  • Most antidepressants block the re-uptake of a
    neurotransmitter of one or more of the bioamines
    serotonin, norepinephrine, dopamine.
  • SSRIs - selective to the serotonin

Serotonin Selective Reuptake Inhibitors SSRI
  • Fluoxetine (Prozac)
  • Sertraline (Zoloft)
  • Paroxetine (Paxil)
  • Fluvoxamine (Luvox)

Side Effects -- SSRIs
  • Headache
  • Anxiety
  • Transient nausea
  • Vomiting
  • Diarrhea
  • Weight gain
  • Sexual dysfunction

  • Usually given in morning, unless sedation occurs
  • Higher doses, especially fluoxetine, can produce
  • Venlafaxine (Effexor), only mildly sedating.
  • Paroxetine associated with weight gain

Antidepressants Others
  • Mirtazapine (Remeron)
  • Maprotiline (Ludiomil)
  • Trazodone (Desyrel)
  • Nefazodone (Serzone)
  • Bupropion (Wellbutrin)
  • Venlafaxine (Effexor)

Antidepressants Monoamine Oxidase Inhibitors
  • Action Inhibit enzyme responsible for the
    metabolism of serotonin, dopamine,
    norepinephrine, and tyramine.
  • Increases levels of norepinephrine and serontonin
    in the CNS
  • Interacts with food -- low tyramine diet (Table

Antianxiety and Sedative-Hypnotic Medication
  • Used for anxiety, not long-term
  • Benzodiazepines (Table 8.14)
  • diazepam (Valium)
  • lorazepam (Ativan)
  • alprazolam (Xanax)
  • Nonbenzodiazepines
  • busipirone (BuSpar)
  • zolpidem (Ambien)
  • Side effects
  • Sedation and CNS depression
  • Tolerance and dependence (Benzos)
  • Avoid Benzo in elderly

  • Amphetamines
  • Used in narcolepsy, ADHD, and obesity

Electroconvulsive Therapy
  • Initiate generalized seizures by an electrical
  • Short-acting anesthetic and muscle relaxant given
  • Repeat procedure 2-3 times per week
  • Produces rapid relief of depressive symptoms
  • Side Effects-hypo or hypertension, bradycardia or
    tachycardia, and minor arrhythmias immediately

Other Biological Treatment
  • Light Therapy (Phototherapy)
  • Reset circadian rhythms
  • Used for SAD
  • Nutritional Therapies