Major Depression 1 Flashcards
The essential feature of major depressive disorder is a
clinical course that is characterized by one or more major depressive episodes without a history of manic, mixed, or hypomanic episodes.
What’s a Dysthymic disorder
Its a chronic disturbance of mood involving depressed mood and at least two other symptoms, and it is generally less severe than major depressive disorder.
Whats the Biogenic amine hypothesis.
Depression may be caused by decreased brain levels of the neurotransmitters norepinephrine (NE), serotonin (5-HT), and dopamine (DA).
Postsynaptic changes in receptor sensitivity. Studies of many antidepressants have demonstrated that desensitization or downregulation of NE or 5-HT1A receptors may relate to onset of antidepressant effects.
What’s the Dysregulation hypothesis.
This theory emphasizes a failure of homeostatic regulation of neurotransmitter systems, rather than absolute increases or decreases in their
activities. Effective antidepressants are theorized to restore efficient regulation to
these systems.
What’s the 5-HT/NE link hypothesis.
This theory suggests that there is a link between 5-HT and NE activity, and that both the serotonergic and noradrenergic systems are involved in
the antidepressant response
Depression- emotional symptoms:
Emotional symptoms may include diminished ability to experience pleasure, loss of
interest in usual activities, sadness, pessimistic outlook, crying spells, hopelessness,
anxiety (present in almost 90% of depressed outpatients), feelings of guilt, and
psychotic features (e.g., auditory hallucinations, delusions).
Depression-PHYSICAL Symptoms:
Physical symptoms may include fatigue, pain (especially headache), sleep
disturbance, appetite disturbance (decreased or increased), loss of sexual interest, and
GI and cardiovascular complaints (especially palpitations).
Depression- intellectual Symptoms:
Intellectual or cognitive symptoms may include decreased ability to concentrate or
slowed thinking, poor memory for recent events, confusion, and indecisiveness.
Depression- Psychomotor Disturbances
Psychomotor disturbances may include psychomotor retardation (slowed physical
movements, thought processes, and speech) or psychomotor agitation.
Criteria for Major Depression Episode
Symptoms must have been present nearly every day for at least 2 weeks.
5 or more of following symptoms:
Depressed nearly every day most of the day
Marked diminished interest in most activites
Significant weight loss or weight gain
Insomnia/Hypersomnia
psychmotor Agitation
Fatigue or loss energy
Feeling of worthlessness
Diminished ability to think or concentrate
Thoughts of death
What’s Electroconvulsive therapy (ECT) and when is it used?
is a safe and effective treatment for major depressive disorder. It is considered when a rapid response is needed, risks of
other treatments outweigh potential benefits, there has been a poor response
to drugs, and the patient expresses a preference for ECT.
Adverse effects of ECT include
confusion, memory impairment (retrograde and
anterograde), treatment emergent mania, headache, nausea, muscle aches, and
cardiovascular dysfunction. Relapse rates during the year following ECT are high
unless maintenance antidepressants are prescribed.
Whats Bright light therapy
(i.e., the patient looking into a 10,000-lux intensity light box
for about 30 min/day) may be used for patients with seasonal affective disorder
and as adjunctive use for major depression.
The acute phase lasts as long as
The maintenance phase lasts
The acute phase of treatment lasts 6 to 10 weeks, and the goal is remission (i.e., absence of
symptoms).
The maintenance phase lasts at least 12 to 36 months, and the goal is to
prevent recurrence of a separate episodes of depression.
first line antidepressants are
The selective serotonin reuptake inhibitors (SSRIs) inhibit the reuptake of 5- HT into the presynaptic neuron.
They are generally chosen as first line
antidepressants because of their safety in overdose and improved tolerability
compared to earlier agents.
TCAs Mechanism of Action:
inhibiting the reuptake of NE and 5-HT, they also block adrenergic, cholinergic, and histaminergic receptors.
The monoamine oxidase inhibitors (MAOIs) - mechanism of Action
phenelzine and tranylcypromine increase the concentrations of NE, 5-HT, and DA within the neuronal synapse
through inhibition of the monoamine oxidase (MAO) enzyme system. Both drugs are nonselective inhibitors of MAO-A and MAO-B.
Selegiline - what is it, MOA
is available as a transdermal patch for treatment of major depression.
It inhibits MAO-A and MAO-B in the brain, but has reduced effects on MAO-A in
the gut.
Bupropion’s MOA
Bupropion’s most potent neurochemical action is blockade of DA reuptake; it
blocks the reuptake of NE to a lesser extent.
venlafaxine and duloxetine MOA
The serotonin-norepinephrine reuptake inhibitors Venlafaxine is an inhibitor of 5-HT and NE reuptake and a weak
inhibitor of DA reuptake. Desvenlafaxine (Pristiq) was recently approved by the
FDA. The dose is 50 mg once daily.
Maprotiline and amoxapine are
inhibitors of NE reuptake, with less effect on 5- HT reuptake.
Mirtazapine MOA
enhances central noradrenergic and serotonergic activity through
the antagonism of central presynaptic α2-adrenergic autoreceptors and
heteroreceptors. It also antagonizes 5-HT2 and 5-HT3 receptors. It also blocks
histamine receptors.
St. John’s wort,
an herbal nonprescription medication containing hypericum,
may be effective for mild to moderate depression, but it is associated with
several drug–drug interactions. Its potency, purity, and manufacture are not
regulated by the FDA.
