NUR240 Chapter Notes - Chapter 16: Major Depressive Disorder, Major Depressive Episode, Seasonal Affective Disorder
Chapter 16: Drugs for Emotional, Mood, and Behavioral Disorders
o Characteristics and Forms of Depression
o Depression: emotional disorder characterized by sad or despondent
mood.
o Major depressive disorder or clinical depression: estimated to
affect 5% to 10% of adults in the United States
o Following criteria for diagnosis of a major depressive disorder
â–Ş Difficulty sleeping or sleeping too much
â–Ş Extremely tired; without energy
â–Ş Abnormal eating patterns
â–Ş Vague physical symptoms
â–Ş Inability to concentrate or make decisions
â–Ş Feelings of despair, guilt, and misery, lack of self-worth
â–Ş Obsessed with death
â–Ş Avoiding psychosocial and interpersonal interactions
â–Ş Lack of interest in person appearance or sex
â–Ş Delusions or hallucinations
o Situational depression: occurs when the depression is the result of a
circumstance in a person’s life, for example, loss of a job or unfavorable
event at home such as death, children leaving home, or divorce
o Dysthymic disorder: characterized by less severe depressive symptoms
that may last several years and prevent a person from feeling well or
functioning normally
o Postpartum depression: up to 80% of women who give birth
experience this; about 10% of new mothers experience a major depressive
episode within 6 months related to the dramatic hormonal shifts that
occur
â–Ş New mothers should be informed about mood disorders prior to
their discharge after giving birth
o Seasonal affective disorder (SAD): enhanced release of the brain
neurohormone melatonin due to lower levels of natural light
â–Ş Exposing patients on a regular basis to specific wavelengths of light
may relieve SAD depression
o Psychotic depression: expression of intense mood shifts and unusual
behaviors; depressive signs and contact with reality, hallucinations,
delusions, and disorganized speech patterns are behaviors observed
o Assessment and Treatment of Depression
o Certain drugs can cause the same symptoms as depression, so this
possibility should be ruled out
o Psychological evaluation is often performed to confirm the diagnosis
o Family history of depressive illness
o Counseling therapies help patients resolve problems verbally
â–Ş Interpersonal (focus on the patients disturbed personal
relationships that both cause and exacerbate depression) and
cognitive-behavioral therapies (help patients change negative styles
of thought and behavior)
▪ Psychodynamic therapies focus on resolving the patient’s internal
conflicts
â–Ş Electroconvulsive therapy (ECT): for patients unresponsive to
cognitive-behavioral or psychodynamic therapies
o Mechanism of Action of Antidepressants
o Antidepressants: medications that treat depression by enhancing mood
â–Ş All antidepressants have a black box warning to monitor for signs of
suicide, especially at the beginning of treatment
• Children and adolescents are at greater risk
o Depression is associated with an imbalance of neurotransmitters in
regions of the brain associated with focused cognition and emotion
o Antidepressants are theorized to exert effects through actions on specific
neurotransmitters in the brain, including norepinephrine, serotonin, and
dopamine
o Two basic mechanisms of drug actions
â–Ş Blocking enzymatic breakdown of norepinephrine
â–Ş Slowing the reuptake of serotonin and norepinephrine
o Primary classes of antidepressant drugs
â–Ş Selective serotonin reuptake inhibitors (SSRIs)
▪ Atypical antidepressants, including serotonin – norepinephrine
reuptake inhibitors (SNRIs)
â–Ş Tricyclin antidepressants (TCAs)
â–Ş Monoamine oxidase inhibitors (MAOIs)
o Selective serotonin reuptake inhibitors (SSRIs): drugs that slow
the reuptake of serotonin into presynaptic nerve terminals
o Treating Depression with SSRIs
o Lack of adequate serotonin in CNS can lead to depression
o SSRIs have a greater safety profile than MAOIs and TCAs
â–Ş Sedation is experienced less frequently, cardiotoxicity is not
observed
o SSRIs selectively target serotonin
o One of the most common side effects of SSRIs relates to sexual
dysfunction
o Serotonin syndrome (SES): may occur when the patient is taking
another medication that affects the metabolism, synthesis, or reuptake of
serotonin, causing it to accumulate in the body
â–Ş Symptoms include mental status change, hypertension, tremors,
sweating, hyperpyrexia, or ataxia
o Treating Depression with Atypical Antidepressants
o Serotonin-norepinephrine reuptake inhibitors: duloxetine and
venlafaxine; specifically inhibit the reabsorption of serotonin and
norepinephrine and elevate mood
o Bupropion inhibits the reuptake of serotonin and also affects the activity of
norepinephrine and dopamine
â–Ş Contraindicated in patients with seizure disorders because it lowers
the seizure threshold
â–Ş Marketed as Zyban for cessation of smoking
