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Same Class, Different Brain Effects: How SSRIs Actually Differ · Understanding the Brain

• 0:03
  Speaker 1: Today we're going to be comparing SSRIs, and in the
• 0:05
  Speaker 1: next future, in the new future, we'll have episodes comparing
• 0:08
  Speaker 1: SNRIs and anxiolytics as well. So you have a 16-year-old
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  Speaker 1: presents with major depressive disorder. A 70-year-old with depression has
• 0:16
  Speaker 1: a history of cardiac arrhythmias. Another patient with OCD, while
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  Speaker 1: a fourth experiences withdrawal symptoms after missing antidepressant doses. Would
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  Speaker 1: you prescribe the same SSRI to all four? Probably not.
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  Speaker 1: SRIs share a common mechanism. They're approved indications, half-lives, adverse effects,
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  Speaker 1: and drug interactions influence medication selection. So let's compare them. Fluoxetine,
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  Speaker 1: also known Prozac, treats major depressive disorder, OCD, panic disorder,
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  Speaker 1: and bulimia nervosa. It's also approved for PMDD. It is
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  Speaker 1: particularly important in pediatric depression because it is FDA approved
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  Speaker 1: for major depression beginning at age 8 and OCD at
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  Speaker 1: age 7. Its half-life increases to approximately 4 to 6
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  Speaker 1: days with chronic use, while its active metabolite can persist
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  Speaker 1: from 14 to 16 days. This long half-life reduces continuation
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  Speaker 1: symptoms but creates prolonged drug interaction risks. Common adverse effects
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  Speaker 1: include insomnia, nausea, activation. Remember the 5-week washout before starting
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  Speaker 1: an MAOI with Prozac. Next is Zoloft or Sertraline. Zoloft
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  Speaker 1: is approved for depression as well, OCD, panic disorder, PTSD,
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  Speaker 1: social anxiety, and PMDD again. Its broad range of indications
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  Speaker 1: makes it useful when depression coexists with anxiety or trauma-related symptoms.
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  Speaker 1: Its half-life is approximately 26 hours. Common side effects, diarrhea, nausea,
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  Speaker 1: sexual dysfunction, and insomnia. FDA is approved for pediatric OCD
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  Speaker 1: beginning at age 6, although pediatric depression treatment is off-label.
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  Speaker 1: Third is Paxil, paroxetine, approved for depression and several anxiety disorders,
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  Speaker 1: including generalized anxiety disorder and panic disorder, and PTSD. Certain
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  Speaker 1: formulations also treat OCD or PMDD as well. Its half-life
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  Speaker 1: is about 21 hours. Paxil has a particularly important disadvantage.
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  Speaker 1: It is continuation syndrome. Abrupt cessation can produce dizziness, nausea,
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  Speaker 1: and electric shock sensations. It also causes weight gain, sexual dysfunction,
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  Speaker 1: and anticholinergic effects. Avoid when possible in older adults. And
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  Speaker 1: remember that it's not approved for pediatric psychiatric treatment. So Zoloft,
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  Speaker 1: Prozac were, but not Paxil. Now we head over to Solexa, Citalopram.
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  Speaker 1: It's FDA approved for adult major depressive disorder. Also prescribed
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  Speaker 1: off-label for certain anxieties. Half-life is about 35 hours. The
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  Speaker 1: biggest concern is QT prolongation. The maximum recommended dose is
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  Speaker 1: 40 mg for most adults, but today we're at 20
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  Speaker 1: mg for patients older than 60 or with certain metabolic
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  Speaker 1: or hepatic risk factors. Patients with significant QT risk may
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  Speaker 1: want another antidepressant. Next is Lexapro. It's approved for MDD
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  Speaker 1: and generalized anxiety disorder. It's particularly relevant to adolescent psychiatry
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  Speaker 1: because it's approved for depression beginning at age 12 and
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  Speaker 1: general anxiety disorder at age 7. Its half-life is 27
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  Speaker 1: to 32 hours, often well-tolerated, although nausea, sexual dysfunction, and
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  Speaker 1: sleeve disturbances remain possible. Next is Luvox. Fluvoxamine is particularly
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  Speaker 1: associated with OCD. It is FDA-approved for OCD in adults
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  Speaker 1: and children beginning at age 8. Its half-life is about
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  Speaker 1: 15 to 20 hours. The major prescribing concern is drug interactions.
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  Speaker 1: Luvox inhibits several hepatic enzymes, particularly CYP1A2 and CYP2C19, potentially
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  Speaker 1: increasing concentrations of other medications, right? Because it's inhibiting the
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  Speaker 1: hepatic enzymes from breaking down anything. Seventh is what they
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  Speaker 1: call Vibred or Velazodone. It's approved for major depressive disorder
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  Speaker 1: in adults. It combines SSRIs with partial agonism at serotonin
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  Speaker 1: 5-HT1A receptors. Half-life is 25 hours. Common adverse effects include diarrhea, nausea,
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  Speaker 1: and insomnia. An important exam details that Velazodone must be
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  Speaker 1: taken with food because fasting substantially reduces absorption. All SSRIs
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  Speaker 1: can produce serotonin syndrome, especially when combined with other serotonergic
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  Speaker 1: medications or herbs, like St. John's Wort. Look for clonus, hyperreflexia, agitation, fever,
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  Speaker 1: and automatic instability. Additional concerns include gastrointestinal bleeding, hypernatremia, sexual dysfunction,
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  Speaker 1: and activation of mania in patients with bipolar disorder. The
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  Speaker 1: FDA also warns about increased suicidal thoughts and behaviors in children, adolescents,
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  Speaker 1: and young adults through age 24. Most SSRIs require, what,
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  Speaker 1: two to four weeks for noticeable improvement and four to
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  Speaker 1: eight weeks for a fuller antidepressant response, although some patients
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  Speaker 1: require longer.