Diagnosis:
MDD – Major Depressive Disorder/Unipolar Disorder
At least five symptoms every day for at least 2 weeks.
Depressed mood = SIG E CAPS
- Sleep disturbances
- Interest in activities lost
- Guilt or worthlessness feelings
- Energy decreased
- Concentration decreased
- Appetite and weight changes
- Psychomotor retardation
- Suicidal ideation
Rating Scales:
- HAM-D: Hamilton rating scale for depression – 18 moderate, 7 normal
- CGT: Clinical Global Impression Scale
- MADRS: Montgomery-Asberg Depression Rating Scale
- PHQ-9: Patient Health Questionnaire
- Beck Depression Inventory
- Quick Inventory of Depressive Symptoms (self-rated)
Treatment:
- Psychotherapy may have longer-lasting effects than drugs, but it takes longer to take effect.
- All anti-depressants are equally as effective, but take 1-2 weeks for effect and 6-8 weeks for full effect. Treat for at least 6 months. An adequate trial is considered to be 4-8 weeks. Look for at least a 50% decrease in symptoms.
- SSRIs are the cheapest and most tolerated drug class: citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, sertraline, vilazodone. SNRIs are very similar, but also decrease seizure threshold: venlafaxine, desvenlafaxine, duloxetine, nefazodone, levomilnacipran
- AE: diarrhea (especially sertraline), drowsiness (fluvoxamine and paroxetine are most sedating, fluoxetine and sertraline are most activating), anxiety, sexual disorder, serotonin syndrome (especially when combined with meperidine, tramadol, MAOI or linezolid), SIADH (especially in elderly), pulmonary HTN (especially paroxetine), weight gain (citalopram, escitalopram and fluoxetine are the most weight neutral)
- Least likely for drug interactions: citalopram and escitalopram, fluoxetine and paroxetine.
- Fluoxetine has the slowest onset and the longest half-life.
- Duloxetine has an indication for diabetic neuropathy
- Limit dose of citalopram to 40 mg due to QT prolongation
- Fluoxetine 90 mg can be taken once weekly
- Venlafaxine is known to cause withdrawal problems
- Symptoms of serotonin withdrawal: dizziness, lightheadedness, feeling faint, shock-like sensations, anxiety, diarrhea, fatigue, gait instability, headache, insomnia, irritability, nausea and vomiting, tremor, visual disturbances and flu-like symptoms
- Serotonin syndrome: MAOI, tramadol, dextromethorphan, meperidine, sympathomimetics, triptans, lithium, TCAs and SNRIs. Symptoms include myoclonus, rigidity, tremors, incoordination, altered mental status, hypothermia, diaphoresis. Use benzos and pressors for symptoms, cyproheptadine can be used to block serotonin
- Patients may respond to a different SSRI or a SNRI if they don’t respond to one or they may want to change to another class.
- May use a second agent to offset actions of another (using trazodone to treat SSRI induced insomnia)
- Can add bupropion to SSRI if patient not responding
- Tricyclic Antidepressants (TCAs): Limited use because of side effects. Amitriptyline, imipramine, clomipramine, desipramine, nortriptyline. They can cause orthostasis, conduction problems (increased QT), anticholinergic side effects, and withdrawn syndromes if abruptly discontinued.
- Monoamine oxidase inhibitors (MAOIs): Non-selective – phenelzine and tranylcypromine. Avoid tyramine-containing foods (aged cheese and meats) due to HTN crisis.
- Mixed serotonergic meds: vilazodone, vortioxetine, trazodone, nefazodone, mirtazapine
- Bupropion – decreases seizure threshold, may cause psychosis in susceptible individuals. May improve sexual dysfunction
- Second generation anti-psychotics can be used to augment theraphy. Most common: aripiprazole, brexipiprazole, quetipine.
- Can try ketamine infusions, lithium, liothyronine, modanifil or scopolamine