SM_117b: Antidepressants Flashcards
Describe indications for antidepressants
Indications for antidepressants
- Generalized anxiety disorder: SSRIs, SNRI, TCA
- OCD: SSRIs, clomipramine
- Panic disorder: all antidepressants
- Social anxiety: SSRIs, SNRIs, MAOis
- PTSD: SSRIs, venlafaxine
- ADHD: buproprion
- Bulimia: SSRIs
- Premenstrual dysphoric disorder: SSRI, SNRIs
- Insomnia: mirtazapine, trazodone, TCAs
- Smoking cessation: bupropion
- Anxiety and depression symptoms in schizophrenia spectrum illness (with an antipsychotic)
- Anxiety and depression in bipolar (with mood stabilizer)
- IBS: SSRIs, TCAs
- Enuresis: imipramine
- Chronic pain especially neuropathic pain: TCAs, SNRIs
- Fibromyalgia: SNRIs
- Migraines; TCA (amitryptiline)
Monoamine theory of depression states ____
Monoamine theory of depression states underlying pathophysiologic basis of depression is a depletion in the levels of serotonin, norepinephrine, and/or dopamine in the CNS
____, ____, and ____ are monoamine neurotransmitters
Serotonin, norepinephrine, and dopamine are monoamine neurotransmitters
(NE and dopamine are catecholamines)
Describe the monoaminergic synapse
Monoaminergic synapse
- Monoamine NTs are synthesized within neurons from common precursors
- Synaptic vesicles take up NT via vesicular monoamine transporter
- On stimulation, vesicles within nerve terminal fuse with the presynaptic terminal and release NT into synaptic cleft
- Released NT interacts with postsynaptic receptors to alter function of postsynaptic cells
- Released NT acts on presynaptic autoreceptors in the nerve terminal to suppress further release
- Plasma membrane transporter proteins take NT from the synaptic cleft back up into the nerve terminal (aka reuptake)
- NT that was reuptaken is degraded or stored in vesicles
Describe treatment principles of antidepressants
Treatment principles of antidepressants
- Take 3-8 weeks to be maximally effective
- Have equivalent response rates and remission rates
- Placebo-drug differences are greatest in more severe depression
- Treat with goal of complete response
- Full relief requires adequate dose
- Switch to another first-line depressant if initial trial does not yield substantive improvement
- Add antidepressant of different class or target residual symptoms with other treatments if partial improvement at the maximally tolerated dose
Common reasons for lack of response include ____, ____, ____, and ____
Common reasons for lack of response include wrong diagnosis, inadequate dose, inadequate length of drug trial / not taking properly, refractory illness / psychiatric comorbidity / complex social stressors
Select first-line antidepressant based on ____, ____, and ____
Select first-line antidepressant based on side effect profile, past response to treatment, and comorbid medical and psychiatric problems
First-line antidepressants include ____, ____, ____, and ____
First-line antidepressants include SSRIs, SNRIs, mirtazapine, and bupropion
Describe common 5HT/NE side effects of antidepressants
Common 5HT/NE side effects of antidepressants
- GI upset (nausea, diarrhea)
- Anxiety, agitation
- Insomnia
- Headahce
- Sweating
- Sexual dysfunction
Serious risks of antidepressant treatment include ____, ____, and ____
Serious risks of antidepressant treatment include increased suicidal thinking / behavior, manic symptoms in people with undiagnosed bipolar disorder, and serotonin syndrome
Serotonin syndrome is a result of ____ often from ____
Serotonin syndrome is a result of increased 5-HT activity in the brain often from combining mutliple serotonergic drugs
Serotonin syndrome involves ____, ____, and ____
Serotonin syndrome involves mental status changes, autonomic hyperactivity, and neuromuscular abnormalities
MAOi is contraindicated with SSRI due to risk of ____
MAOi is contraindicated with SSRI due to risk of serotonin syndrome
Many antidepressants cause ____ symptoms when stopped
Many antidepressants cause withdrawal symptoms when stopped
Antidepressant classes include ____, ____, ____, ____, and ____
Antidepressant classes include
- Selective serotonin reuptake inhibitors
- Serotonin-norepinephrine reuptake inhibitors
- Tricyclic antidepressants
- Monoamine oxidase inhibitors
- Other
SSRIs act by ____
SSRIs act by blocking 5-HT transporter but have different effects at other receptors
(qd dosing, low toxicity)
____ has the longest half-life of the SSRIs and requires long washout if cross-tapering to MAOis
Fluoxetine (Prozac) has the longest half-life of the SSRIs and requires long washout if cross-tapering to MAOis
____ is an SSRI that is a potent CYP2C6 inhibitor, has anticholinergic side effects, and has the shortest half life
Paroxetine (Paxil) is an SSRI that is a potent CYP2C6 inhibitor, has anticholinergic side effects, and has the shortest half life
____ is an SSRI with higher risk for GI side effects and is often the preferred agent in pregnancy
Sertraline (Zoloft) is an SSRI with higher risk for GI side effects and is often the preferred agent in pregnancy
____ is an SSRI that has dose-dependent QTc prolongation and should be avoided in people with cardiac comorbidities
Citalopram (Celexa) is an SSRI that has dose-dependent QTc prolongation and should be avoided in people with cardiac comorbidities
____ is an SSRI that is an enantiomer of citalopram with fewer side effects
Escitalopram (Lexapro) is an SSRI that is an enantiomer of citalopram with fewer side effects
____ is an SSRI approved only for OCD
Fluvoxamine (Luvox) is an SSRI approved only for OCD
SNRIs act by ____, are helpful for ____, and have a risk of ____ at higher doses
SNRIs act by increasing 5HT at low doses and NE at higher doses, are helpful for neuropathic pain, and have a risk of HTN at higher doses
(venlafaxine, desvenlafaxine, duloxetine)
Describe TCAs
TCAs
- Inhibit NE and 5HT reuptake
- Often used for chronic pain
- Sedation and weight gain common
- Anticholinergic side effects common: dry mouth, constipation, urinary retention, blurry vision
- Cardiovascular side effects common
- Risk of seizures
- Lethal in overdose
