Mianserin

Overview of the antidepressant drug Mianserin

2D structure of Mianserin

Mianserin is a tetracyclic antidepressant (TeCA) that is primarily used in the treatment of major depressive disorder. It was first introduced in the 1970s and is known for its unique pharmacological profile, which includes antagonism of various neurotransmitter receptors.

Pharmacology

Mianserin acts as an antagonist at several receptor sites, including the histamine H1 receptor, alpha-2 adrenergic receptor, and various serotonin receptors. This receptor antagonism contributes to its antidepressant effects. Unlike many other antidepressants, mianserin does not inhibit the reuptake of serotonin or norepinephrine, which distinguishes it from other classes such as selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs).

Mechanism of Action

Mianserin's antidepressant effects are thought to be primarily due to its antagonism of presynaptic alpha-2 adrenergic receptors, which leads to increased release of norepinephrine and serotonin. Additionally, its antagonism of serotonin receptors, particularly the 5-HT2A and 5-HT2C subtypes, may contribute to its mood-enhancing properties.

Ball-and-stick model of Mianserin

Clinical Use

Mianserin is used in the treatment of major depressive disorder, particularly in patients who may not respond well to other antidepressants. It is sometimes preferred in patients who experience significant side effects from SSRIs or TCAs, as it tends to have a different side effect profile.

Side Effects

Common side effects of mianserin include sedation, weight gain, and dizziness. The sedative effects are primarily due to its potent antagonism of the histamine H1 receptor. Mianserin is also associated with a risk of agranulocytosis, a potentially serious condition involving a decrease in white blood cells, which necessitates regular blood monitoring in some patients.

Chemistry

Mianserin is a tetracyclic compound, meaning it has four interconnected rings in its chemical structure. This structure is similar to that of other tetracyclic antidepressants, but distinct from the tricyclic structure of TCAs.

Structure of Esmianserin, an enantiomer of Mianserin

Related Compounds

Mianserin is closely related to mirtazapine, another tetracyclic antidepressant that shares a similar mechanism of action. Mirtazapine is often used as an alternative to mianserin, particularly in the United States where mianserin is not available.

History

Mianserin was developed in the 1970s and was one of the first antidepressants to be marketed as a tetracyclic compound. It was initially introduced in Europe and has since been used in various countries around the world.

Related Pages

• Antidepressant
• Tetracyclic antidepressant
• Mirtazapine
• Major depressive disorder

Mianserin in tablet form

See Also

• Selective serotonin reuptake inhibitor
• Tricyclic antidepressant
• Serotonin–norepinephrine reuptake inhibitor