Anti-depressants and Antipsychotic (2).pptx

Antipsychoti cs and antidepress ants Done by: Dr. Rawan Al- Gharaibeh Depression: affective disorder in which a person experiences sadness that is much more severe and longer lasting than is warranted by the event that seems to have precipitated it, with a more intense mood; the condition may...

Antipsychoti cs and antidepress ants Done by: Dr. Rawan Al- Gharaibeh Depression: affective disorder in which a person experiences sadness that is much more severe and longer lasting than is warranted by the event that seems to have precipitated it, with a more intense mood; the condition may not even be traceable to a specific event or stressor.  The etiology of depression is not known but there is evidence that a major factor is a reduction in the amount of neurotransmitters such as serotonin 5-HT or norepinephrine at the junctions between neurons in the brain.  Many of the drugs currently used to treat effective disorders increase the levels of serotonin, dopamine, and norepinephrine concentrations in the CNS. Early and aggressive antidepressant treatment increases the chances for full remission. The first 6-8 weeks of therapy constitute the acute phase.  The primary goals during this time (first 6-8 weeks ) are to obtain a response to drug therapy and to improve the patient’s symptoms. It is currently recommended that antidepressant drug therapy be maintained at the effective dose for an additional 8-14 months after remission of depressive symptoms. Therapeutic response is measured primarily by subjective patient feedback.  A therapeutic non-response to antidepressant drug therapy is defined as failure to respond to at least 6 weeks of therapy with adequate drug dosages. Therefore, dosage optimization, which involves careful upward titration of medication dose for several weeks, is recommended before concluding that a given drug is ineffective in treating a particular patient. Pharmacology overview: Older generation:  tricyclic antidepressant (TCA) drugs  monoamine oxidase inhibitors (MAOIs) Newer generation:  selective serotonine reuptake inhibitors (SSRIs)  serotonine norepinephrine reuptake inhibitors (SNRIs)  miscellaneous. 1. Monoamine oxidase inhibitors MAOIs:. Isocarboxazid, phenelzine, and tranylcypromine. They are now rarely used >> This is partly because newer, safer drugs are now available A serious disadvantage to MAOI use is their potential to cause a hypertensive crisis when taken with a substance containing tyramine, which is found in many common foods and beverages. 2. Tricyclic antidepressants:.  Amitriptyline.  Clomipramine.  Imipramine. Now TCAs are generally considered second-line drug therapy for patients for whom the newer drugs are ineffective or as adjunct therapy with newer drugs. TCAs are so named because of their characteristic three-ring chemical stricture.. Mechanism of action: TCAs are believed to work by correcting imbalance in the neurotransmitter concentrations of serotonin and norepinephrine at the nerve endings in the CNS This is accomplished by blocking presynaptic reuptake of the neurotransmitters. Some also believe that these drugs may help regulate malfunctioning neurons (the dysregulation therapy). Indications. Originally used to treat depression Currently, TCAs are most commonly used to treat neuropathic pain syndromes and insomnia. Clomipramine Imipramine Contraindications.  known drug allergy  pregnancy. TCAs are also not recommended in patient with:  any acute or chronic cardiac problems  history of seizures >>> because both conditions are associated with a greater likelihood of death upon TCA overdose. Adverse effects: constipation  urinary retention disturbances in cardiac conduction Hypotension sexual dysfunction.. 4. Tetracyclic antidepressants:  Maprotiline  Mirtazapine Drug profile: Mirtazapine (remeron):  Associated with sedation due to histamine H1 receptor activity.  Dosed once daily at bedtime.  Increase appetite.. 4. Selective serotonin reuptake inhibitors (SSRIs): Citalopram, Escitalopram, Fluoxetine, Paroxetine, Sertraline. 5. Serotonin norepinephrine reuptake inhibitors (SNRIs): Duloxetine, Venlafaxine.. They are associated significantly with fewer and less severe systemic adverse effects, compare with older-generation. Patients should be educated that antidepressant drugs commonly must be taken for several weeks before full therapeutic effects are realized. This requires some patience and faithful dosing on the part of patients.. Mechanism of action:. Indications: Depression is their primary indication. Have shown benefit in treating a variety of other mental and physical disorders:  bipolar disorder  eating disorders  obsessive-compulsive disorder Adverse effects. Interactions: The newer-generation antidepressants are highly bound to albumin. Some of these drugs may also inhibit cyt P- 450 enzymes,  Antipsychotic drugs Mental disorders are now thought to be caused by some inherent dysfunction within the brain that leads to abnormal thought processes and responses. Psychosis: is a severe mental disorder that often impairs mental function to the point of causing significant disability in performing the activities of daily living.  A hallmark of psychosis is a loss of contact with reality. The primary psychotic disorders are schizophrenia and depressive and drug – induced psychoses.  The dopamine hypothesis of psychotic illness grows out of the observation that psychotic patients often have excessive dopaminergic activity in the brain >> Drug therapy is therefore aimed at reducing this activity. Because no diagnostic laboratory tests are available, patient assessment and response must be carefully evaluated to determine the basis of a particular problem. Schizophrenia: is the most common type of psychosis It can be very debilitating and prevents affected individuals from functioning in society. Characteristics of schizophrenia include:  Hallucinations  paranoia  Delusions  speech abnormalities  affective problems.  Mania: with its associated bipolar illness (i.e., manic depressive illness), is characterized by periods of extreme overactivity and excitement. Bipolar disorder: involves extremes of depression alternating with hyperactivity and excitement. >> This condition may reflect a biochemical imbalance followed by overcompensation on the part of neurons and their inability to re-establish stability. Antipsychotics: There are few overall differences between antipsychotics in terms of mechanism of action. The selection of an antipsychotic is based primarily on the patient’s tolerance and the need to minimize adverse effects, Antipsychotic drug therapy does not normally provide a cure for psychoses Atypical antipsychotics differ from conventional drugs in that they tend to have better adverse effects. Antipsychotics: Older generation (conventional antipsychotics):  Thioridazine.  Trifluoperazine.  Chlorpromazine.  Haloperidol. Newer generation (atypical antipsychotics):  Clozapine.  Olanzapine.  Risperidone.  Aripiprazole. Mechanism of action: One thing that all antipsychotics have in common is some degree of blockage of dopamine receptors in the brain, which decrease the dopamine concentration in the CNS. Specifically, the older phenothiazines block the receptors to which dopamine normally binding postsynaptically in certain areas of the CNS, such as the limbic system and the basal ganglia. >>> These are the areas associated with emotions, cognitive function, and motor function.  The newer atypical antipsychotic drugs block specific dopamine receptors called dopamine 2 receptors, as well as specific serotonin receptors in the brain known as serotonin 2 receptors >>>> These more refined mechanisms of action of atypical are responsible for their improved efficacy and safety profiles, compared with older drugs. Dopamine Hypothesis and Psychosis. Adverse effects: CNS effects: drowsiness, neuroleptic malignant syndrome extrapyramidal symptoms Cardiovascular effects: postural hypotension, electrocardiogram changes Lithium The original drugs still currently available that can effectively alleviate the symptoms of acute mania are the lithium salts, lithium carbonate and lithium citrate. Lithium is also effective for the maintenance treatment of bipolar disorder. One possible explanation for its effectiveness is that it potentiates serotonergic neurotransmission. lithium has a narrow therapeutic range and requires blood level monitoring.  A variety of medications may be used in conjunction with lithium to regulate mood or achieve stability in manic or hypomanic patients include:  benzodiazepines  antipsychotic drugs  antiepileptic drugs  dopamine receptor agonists.  The antiepileptic valproic acid, lamotrigine, and carbazepine are commonly preferred to lithium These drugs are often effective in treating mania, hypomania, and to lesser degree, depressive symptoms. The atypical antipsychotic drugs risperidone, olanzapine,and ziprasidone can also be effective in treating mania and hypomania Nursing Implications: Provide simple explanations about the drug, its effects, and the length of time before therapeutic effects can be expected Advise patients to avoid abrupt withdrawal Advise patients to change positions slowly to avoid postural hypotension and possible injury  The combination of drug therapy and psychotherapy is emphasized because patients need to learn and acquire more effective coping skills Only small amounts of medications should be dispensed at a time to minimize the risk of suicide attempts Simultaneous use of these drugs with alcohol or other CNS depressants can be fatal  Antidepressants. Inform patients that it may take several weeks to see therapeutic effects, monitor patients closely during this time, assess for suicidal tendencies, and provide support Tricyclics may need to be weaned and discontinued before undergoing surgery to avoid interactions with anesthetic drugs  Monitor for adverse effects, and discuss with patients Encourage patients to wear medication ID badges naming the drugs being taken Caffeine and cigarette smoking may decrease effectiveness of medication therapy  Advise patients to avoid abrupt withdrawal  Advise patients to change positions slowly to avoid postural hypotension and possible injury. Antipsychotics Instruct patients to wear sunscreen because of photosensitivity Tell patients to avoid taking antacids or antidiarrheal preparations within 1 hour of a dose Long-term haloperidol therapy may result in tremors, nausea, vomiting, or uncontrollable shaking of small muscle groups; report these symptoms to the physician Oral forms may be taken with meals to decrease GI upset These drugs may cause drowsiness, dizziness, or fainting; instruct patients to change positions slowly  Monitor for therapeutic effects  Monitor mental alertness, cognition, affect, mood, ability to carry out activities of daily living, appetite, and sleep patterns  Monitor potential for self-injury during the delay between the start of therapy and symptomatic improvement For antidepressants. Improved sleep patterns and nutrition Increased feelings of self-esteem Decreased feelings of hopelessness Increased interest in self and appearance Increased interest in daily activities Fewer depressive manifestations or suicidal thoughts/ideations For antipsychotics Improved mood and affect Alleviation of psychotic symptoms and episodes Decreased hallucinations, paranoia, delusions, garbled speech, and inability to cope For lithium Less mania Therapeutic lithium levels of 0.6 to 1.2 mEq/L