Antidepressants Flashcards
What are some common SSRI
Fluoxetine
Paroxetine
Sertraline
Citalopram
What is the mechanism of SSRI
Binds to Serotonin transporter (SERT) → Inhibition of serotonin reuptake in synaptic clefts → increased serotonin levels in synaptic space
Name 4 important side effects of SSRIs
- Most important: Serotonin Syndrome
- Nausea
- insomnia
- sexual dysfunction
What is serotonin syndrome?
Serotonergic overactivity due to the use of serotonin drugs either due to therapeutic dose or overdose of serotonergic drug, use of multiple serotonergic drugs, or interactions with CYP-450 inhibitors
Symptoms of Serotonin syndrome
- Hyperthermia
- Tremor
- Sexual dysfunction
How to treat sexual dysfunction from SS
Cyproheptadine or other 5-HT2 blockers can be given to reduce the effects caused by the excessive serotonin in synaptic cleft
Why is SSRI better than TCA
- Greater 5-HT reuptake selectivity than TCAs (Fluoxetine 50x more selective
Citalopram 1000x more selective) - Fewer adverse effects than TCA
What is a common NARI
Ruboxetine
Why is NARI very commonly used?
- Greater NA reuptake selectivity than TCAs. (Approximately 1000-fold selectivity for NA over 5-HT)
- Fewer adverse effects than TCAs and SSRIs
Adverse effects of ruboxetine (NARI)
- Anticholinergic side effects (Dry mouth, Constipation)
- Insomnia (Increased NA activities in CNS)
- Tachycardia (Increased NA activities → sympathetic activation in CVS)
What are SNRIs?
Serotonin and Noradrenaline reuptake Inhibitors (SNRIs)
What are some commonly used SNRIs?
- Venlafaxine
- Desvenlafaxine (synthetic metabolite of venlafaxine)
- Duloxetine
What is the mechanism of SNRIs?
Inhibition of serotonin and norepinephrine reuptake in synaptic cleft → ↑ serotonin and norepinephrine levels
Side effects of SNRIs
Similar to SSRIs
- Nausea
- Insomnia
- Sexual dysfunction
- Serotonin syndrome when combined with other serotoninergic drugs and MAOIs
- Withdrawal effects may be stronger compared to SSRIs or TCAs
Name some other antidepressants (atypical antidepressants)
- Mirtazapine
- Bupropion