Pharmacology
Summary
Bupropion, an atypical antidepressant, acts by inhibiting the norepinephrine transporter (NET) and the dopamine transporter (DAT), giving rise to CNS activating effects. This pharmacologic property also makes bupropion effective in treating tobacco dependence. However, it can induce seizures, and is contraindicated in conditions where the seizure threshold may already be reduced, like bulimia and anorexia. Unique among antidepressants, bupropion doesn't induce sexual dysfunction and is less prone to causing weight gain, addressing two common concerns associated with many other antidepressant therapies.
The landscape of atypical antidepressants extends to drugs like mirtazapine and trazodone. Mirtazapine functions by blocking alpha-2 receptors, enhancing the presynaptic release of serotonin and norepinephrine. Additionally, its antagonism of 5HT-2, 5HT-3, and H1 histamine receptors can lead to side effects like sedation and weight gain. However, like bupropion, it doesn't commonly induce sexual dysfunction. Trazodone is characterized as a serotonin modulator, as it both antagonizes 5-HT receptors and inhibits 5-HT reuptake. It also blocks H1 histamine and alpha-1 receptors. Clinically, trazodone may cause priapism, a potentially dangerous prolonged erection, as well as sedation, orthostatic hypotension, and sexual dysfunction. Additionally, similar to other agents affecting serotonin, trazodone can cause serotonin syndrome, a potentially life-threatening condition.
Lesson Outline
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FAQs
Bupropion, an atypical antidepressant, acts by inhibiting the norepinephrine transporter (NET) and the dopamine transporter (DAT). This leads to an increased concentration of norepinephrine and dopamine in the brain, exerting activating effects on the CNS.
Bupropion should be avoided in patients with conditions like bulimia or anorexia nervosa because of an increased risk of seizures. Apart from its potential to induce seizures, bupropion is not associated with side effects typical of other antidepressants, such as sexual dysfunction and weight.
Mirtazapine, an atypical antidepressant, acts primarily by blocking alpha-2 receptors, leading to an increased release of serotonin and norepinephrine from presynaptic neurons. It also antagonizes 5HT-2, 5HT-3, and H1 histamine receptors. Common side effects include sedation and weight gain; however, mirtazapine does not cause sexual dysfunction.
Trazodone, classified as a serotonin modulator, both antagonizes specific 5-HT receptors and inhibits 5-HT reuptake. It also inhibits 5HT-2 and alpha-1 receptors. Trazodone can cause side effect such as sedation, priapism, orthostatic hypotension, and sexual dysfunction. There's also a risk of serotonin syndrome with its use.
