Depression and Antidepressants Overview

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Questions and Answers

What is a common side effect of blocking histamine H1 receptors?

Sedative side effects (correct)

Dry mouth

Life-threatening arrhythmias

Orthostatic hypotension

Which drug is specifically indicated for treating nocturnal enuresis?

Bupropion

Imipramine (correct)

Venlafaxine

Amitriptyline

What serious side effect can occur due to tricyclic antidepressants (TCAs)?

Weight gain

Sedation

Life-threatening arrhythmias (correct)

Dry mouth

Which mechanism is primarily utilized by venlafaxine at high doses?

Inhibits dopamine Signup and view all the answers

What is a common side effect associated with venlafaxine treatment?

Elevated blood pressure Signup and view all the answers

Which of the following TCA is listed as being best evidence for neuralgia treatment?

Amitriptyline Signup and view all the answers

What is a key characteristic of SNRIs compared to TCAs?

Lower side effect profile Signup and view all the answers

Which of these is a common side effect reported for tricyclic antidepressants?

Constipation Signup and view all the answers

Which of the following subclasses of antidepressants primarily inhibits the reuptake of serotonin?

Selective Serotonin Reuptake Inhibitors (SSRI) Signup and view all the answers

What is a common side effect associated with SSRIs?

Erectile dysfunction Signup and view all the answers

Which of the following medications is an example of a Selective Serotonin Reuptake Inhibitor?

Citalopram Signup and view all the answers

The primary action of SSRIs is to:

Increase the availability of serotonin at the synapse Signup and view all the answers

What condition is considered the first-line treatment with SSRIs?

Depression Signup and view all the answers

Which SSRI is noted for potentially causing sedation in some patients?

Fluvoxamine Signup and view all the answers

In addition to depression, SSRIs are also used to treat which of the following disorders?

Obsessive-compulsive disorder Signup and view all the answers

Which of the following is NOT associated with an increased level of serotonin due to SSRI use?

Increased appetite Signup and view all the answers

What is a key action of Bupropion in the treatment of depression?

Increases presynaptic availability of norepinephrine Signup and view all the answers

Which of the following antidepressants is associated with a risk of hepatotoxicity?

Phenelzine Signup and view all the answers

Which drug acts as an antagonist to neuronal nicotinic Ach receptors?

Bupropion Signup and view all the answers

Which of the following MAOIs is selective for MAO-B?

Selegiline Signup and view all the answers

What side effect is commonly associated with Amoxapine?

Parkinsonian syndrome Signup and view all the answers

What is a common mechanism shared by MAOIs?

Prevention of monoamine degradation Signup and view all the answers

What distinguishes Reboxetine from other norepinephrine reuptake inhibitors?

It has no anticholinergic side effects. Signup and view all the answers

Which of the following drugs does not have a direct effect on the serotonin system?

Bupropion Signup and view all the answers

What type of depression is characterized by a reaction to significant stressors or adverse life situations?

Reactive depression Signup and view all the answers

Which symptom is NOT typically associated with major depressive disorder?

Excessive energy Signup and view all the answers

What is one of the primary diagnostic tools used to identify mental health disorders, including depression?

Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) Signup and view all the answers

Which of the following is considered a genetic cause of depression?

Neurotransmitter dysfunction Signup and view all the answers

Which form of depression is characterized by a prolonged period of at least two years with persistent symptoms?

Chronic depression (Dysthymia) Signup and view all the answers

Which of the following symptoms is least likely to indicate an underlying depression?

Sudden increase in appetite Signup and view all the answers

What is one treatment method commonly used for endogenous depression?

Antidepressants Signup and view all the answers

Which type of depression is characterized by fluctuations in mood and is associated with episodes of mania?

Bipolar disorder Signup and view all the answers

What is the primary mechanism by which MAOIs prevent the destruction of monoamines?

Inhibiting the action of MAO Signup and view all the answers

What serious condition can result from ingesting tyramine-containing foods while on MAOIs?

Hypertensive crisis Signup and view all the answers

Which food should be avoided entirely while taking MAOIs?

Aged cheeses Signup and view all the answers

What advantage do RIMAs have over traditional MAOIs?

Lower likelihood of serious dietary interactions Signup and view all the answers

Which of the following is a common side effect associated with MAOIs?

Agitation or excess stimulation Signup and view all the answers

Which SSRI is known to primarily inhibit CYP3A4?

Fluvoxamine Signup and view all the answers

Which SSRI would likely produce a clinical response more rapidly than a tricyclic antidepressant?

Fluoxetine Signup and view all the answers

Which of the following is a symptom of Serotonin syndrome?

Rigid muscles Signup and view all the answers

What describes the therapeutic index of SSRIs in comparison to tricyclic antidepressants?

Wide therapeutic index Signup and view all the answers

What is a common outcome of abruptly discontinuing SSRIs?

Flu-like symptoms Signup and view all the answers

Fluoxetine and paroxetine are potent inhibitors of which cytochrome P450 enzyme?

CYP2D6 Signup and view all the answers

What advantage do SSRIs have over tricyclic antidepressants regarding suicide rates?

They significantly lower overall suicide rates. Signup and view all the answers

Study Notes

Depression & Antidepressants

Depression is a mood disorder with various types and causes.
Reactive depression is a reaction to life stressors.
Endogenous depression (Major Depressive Disorder, MDD) may stem from genetic factors, physiological/metabolic disturbances, and can come about at any time in life.
Types of depression include major depression, chronic depression (dysthymia), atypical depression, bipolar disorder/manic depression, and seasonal depression (SAD).
Causes of depression include genetics (managed by antidepressants + ECT), reactive factors (death/abuse), medications (like reserpine, oral contraceptives), spontaneous cases (managed by antidepressants), the neurotrophic hypothesis, and monoamines & other neurotransmitters.

Symptoms

Symptoms include persistently sad, anxious, or empty moods.
Loss of pleasure in activities (anhedonia).
Feelings of worthlessness, guilt, and/or hopelessness.
Extreme fatigue or lack of energy.
Difficulty concentrating and making decisions.
Irritability and restlessness.
Sleep disturbances and changes in appetite or weight.
Physical symptoms not responding to treatment (like pain and gastrointestinal complaints).
Thoughts of suicide or death.
Poor self-image or self-esteem, including verbal self-reproach.

Diagnosis

Diagnosis involves a thorough patient and family history.
Blood tests for hypothyroidism may be performed.
Current medications are noted.
DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th Edition) is used for diagnosis.
It's important that one or two main symptoms are observed along with five other symptoms, consistently and daily for at least two weeks.

Treatment

Treatments for depression include psychotherapy and electroconvulsive therapy (ECT).
Natural alternatives and medication are also options.
Common antidepressant medications include SSRIs, SNRIs, TCAs, NDRIs, MAOIs, and TeCAs.

Clinical Indications

Mood disorders, anxiety disorders, eating disorders, chronic pain, and incontinence are clinical indications for using antidepressants.

Neurotransmitters & Catecholamine Hypothesis

Neurotransmitters pass signals in the brain.
A smaller amount of neurotransmitters can cause depression.

Receptor Sensitivity Hypothesis

Post-synaptic receptors become overly sensitive.
Suicidal and depressed patients often have increased pre-synaptic 5-HT1 and 5-HT2 receptors.
Chronic use of antidepressants affects the sensitivity of pre- and post-synaptic receptors.

Therapeutic Effect

Antidepressant effects typically appear after 2-4 weeks.
Side effects and improved sleep might be apparent earlier, but bear in mind a risk of suicide.
Follow-up is necessary, lasting up to one year for a first episode and up to 3 years for repeated episodes.

Major and Subclasses of Antidepressants

Antidepressants are grouped based on physiological actions: reuptake inhibition and enzyme inhibition.

Reuptake Inhibitors

SSRIs: Selective serotonin reuptake inhibitors are used for depression and anxiety.
- Includes Citalopram, Escitalopram, Fluoxetine, Fluvoxamine, Paroxetine, and Sertraline.
SNRIs: Selective serotonin and norepinephrine reuptake inhibitors.
- Includes venlafaxine, desvenlafaxine, duloxetine, and milnacipran.
TCAs: Tricyclic antidepressants
- Include amitriptyline, clomipramine, doxepin, imipramine/desimipramine, and nortriptyline
NARIs: Nor-adrenaline reuptake inhibitors
- Include Maprotiline and Amoxapine.

Enzyme Inhibitors

MAOIs: Monoamine oxidase inhibitors:
- Phenelzine, Tranylcypromine, and Moclobemide.
- MAOIs are the first antidepressants discovered, and work by preventing the breakdown of monoamines in the brain.

Clinical Response to SSRIs

SSRIs produce more rapid clinical responses than tricyclic antidepressants.

Serotonin Syndrome

High doses of SSRIs or a combination with TCAs or MAOIs can lead to serotonin syndrome.
Symptoms include rigidity, hyperthermia, confusion, and autonomic instability.
Prevention involves avoiding concurrent use of SSRIs with other serotonin-increasing drugs. Giving a drug free period before switching from an SSRI to another serotonin drug.

Antidepressant Discontinuation Syndrome

Symptoms can occur when stopping antidepressants abruptly.
Symptoms include flu-like symptoms, insomnia, imbalances, nausea, sensory disturbances, and hyperarousal.

Advantages of SSRIs

SSRIs have fewer cardiac and anticholinergic side effects compared to other antidepressants. These can also be safely used in overdoses. SSRIs are better tolerated and are non-sedating.
SSRIs show some evidence of reducing overall suicide rates more effectively than tricyclic antidepressants.

Tricyclic Antidepressants (TCAs)

TCAs block the reuptake of norepinephrine and serotonin.
Common side effects include sedation, dry mouth, blurred vision, weight gain, constipation, urinary retention, palpitations, and tachycardia.
Serious side effects include postural hypotension, life-threatening arrhythmias, sexual dysfunction, raised intra-ocular pressure, and a lower seizure threshold.

Selective Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)

Venlafaxine is a common SNRI that inhibits serotonin and norepinephrine reuptake.
Moderate doses affect norepinephrine, while higher doses can also affect dopamine.

Tetracyclics and Unicyclics

These include Mirtazapine, Mianserin, Bupropione, maprotiline, amoxapine, vilazodone, quetiapine.
They affect norepinephrine and serotonin reuptake, and can increase their release.

New Antidepressants (Bupropion)

Bupropion is a non-selective inhibitor of dopamine and norepinephrine reuptake.
It has no direct effect on the serotonin system.
It also acts as an antagonist to nicotinic acetylcholine receptors.

Noradrenaline Reuptake Inhibitors (NARIs)

NARIs like reboxetine, Maprotiline, and Amoxapine have anticholinergic side effects and are reasonably tolerated,
However, Amoxapine may cause parkinsonian syndrome and antipsychotic symptoms.

Enzyme Inhibitors (MAOIs)

MAOIs prevent the breakdown of monoamines.
Side effects include a higher risk of hypertensive crisis due to interactions with tyramine-containing foods.
Dietary restrictions are essential to avoid this.

Reversible Inhibitors of Monoamine Oxidase Type A (RIMAs)

RIMAs (like moclobemide) are more selective than older MAOIs.
They generally have fewer dietary restrictions and improved tolerability.

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Description

This quiz explores the various types of depression and their causes, along with the role of antidepressants in treatment. Learn about common symptoms, genetic factors, and how different forms of depression manifest. Test your understanding of this complex mood disorder.