Antidepressants Flashcards
How does the efficacy of different antidepressants differ?
Antidepressant efficacy is similar so selection is based on past history of a response, side effect profile and coexisting medical conditions.
There is a delay typically of ____weeks after a therapeutic dose is achieved before symptoms improve.
2-4
If no improvement is seen after a trial of adequate length (________) and adequate dose, either switch to another antidepressant or augment with another agent.
at least 2 months
What is the prophylaxis; how long should a patient keep taking anti-depressants even if they feel better after a depressive episode?
- First episode continue for 6mth to a year
- Second episode continue for 2 years
- Third episode disucuss life long
Give 5 classifications of antidepressants
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
Tricyclic antidepressants (TCA) are very effective but have a potentially unacceptable side effect profile i.e.???
- antihistaminic, anticholinergic, antiadrenergic
- Lethal in overdose (even a one week supply can be lethal!)
- Can cause QT lengthening even at a therapeutic serum level
Tertiary TCAs have tertiary ______ side chains
Amine
Tertiary TCAs have tertiary amine side chains.
Side chains are prone to? Give examples
Cross react with other types of receptors which leads to more side effects
Examples:
- Imipramine
- amitriptyline
- doxepin
- clomipramine
Secondary tricyclic antidepressants (TCAs) are of metabolites of which amines?
Tertiary amines
How do secondary tricyclic antidepressants work?
primarily block noradrenaline
What are the side-effects of secondary TCAs?
Give examples
Side chains are prone to cross react with other types of receptors which leads to more side effects
- Desipramine
- notrtriptyline
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
How do MAOIs work?
Bind irreversibly to monoamine oxidase thereby preventing inactivation of amines such as norepinephrine, dopamine and serotonin leading to increased synaptic levels.
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
MAOIs aree very effective for what type of depression?
Are very effective for resistant depression
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
MAOIs have what side effects?
- Side effects include orthostatic hypotension
- weight gain
- dry mouth
- sedation
- sexual dysfunction
- sleep disturbance
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
MAOIs can have a “cheese reaction”… what is it?
Hypertensive crisis can develop when MAOI’s are taken with tyramine-rich foods or sympathomimetics. *Cheese + Wine Reaction!!
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
Which foods and drinks must patients taking MAOIs stay away from?
Why?
Hypertensive crisis can develop when MAOI’s are taken with tyramine-rich foods or sympathomimetics.
*Cheese + Wine Reaction!!
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
What can happen if you take MAOIs with meds that increase serotonin or have a sympathomimetic action?
Serotonin syndrome
- abdominal pain
- diarrhea
- sweats
- tachycardia
- HTN
- myoclonus
- irritability
- delirium
- Can lead to hyperpyrexia
- cardiovascular shock and death
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
If MAOIs are taken with meds that increase serotonin or have a sympathomimetic action it can cause serotonin syndrome… what are the symptoms?
Serotonin syndrome
- abdominal pain
- diarrhea
- sweats
- tachycardia
- HTN
- myoclonus
- irritability
- delirium
- Can lead to hyperpyrexia
- cardiovascular shock and death
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
If MAOIs are taken with meds that increase serotonin or have a sympathomimetic action it can cause serotonin syndrome… How can you avoid this from happening?
To avoid need to wait 2 weeks before switching from an SSRI to an MAOI.
The exception of fluoxetine where need to wait 5 weeks because of long half-life.
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
How do selective serotonin reuptake inhibitors (SSRIs) work?
Block the presynaptic serotonin reuptake
Antidepressants used in psychiatry fall into the following categories;
- Tricyclics (TCAs)
- Monoamine Oxidase Inhibitors (MAOIs)
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
What are SSRIs they used to treat?
Treat both anxiety and depressive sx