Antidepressants Mechanism of Action
Antidepressants are a class of medications used to treat depression and other mood disorders. They work by affecting the levels of certain chemicals in the brain called neurotransmitters, which play a role in regulating mood.

Serotonin Reuptake Inhibitors (SSRIs)
- SSRIs are the most commonly prescribed type of antidepressants.
- They work by blocking the reabsorption (reuptake) of serotonin in the brain, leading to increased levels of this neurotransmitter.
- By increasing serotonin levels, SSRIs help regulate mood and alleviate symptoms of depression.

Tricyclic Antidepressants (TCAs)
- TCAs work by blocking the reuptake of serotonin and norepinephrine in the brain.
- By increasing levels of these neurotransmitters, TCAs help improve mood and reduce symptoms of depression.
- However, TCAs have more side effects compared to SSRIs and are usually prescribed when other treatments have not been effective.

Monoamine Oxidase Inhibitors (MAOIs)
- MAOIs work by inhibiting the activity of the enzyme monoamine oxidase, which breaks down neurotransmitters like serotonin, norepinephrine, and dopamine.
- By blocking the breakdown of these neurotransmitters, MAOIs increase their levels in the brain, leading to improved mood and decreased symptoms of depression.
- MAOIs are often used as a last resort due to their potential interactions with certain foods and medications.

Atypical Antidepressants
- Atypical antidepressants work in various ways to regulate neurotransmitter levels in the brain.
- For example, bupropion increases levels of dopamine and norepinephrine, while mirtazapine enhances serotonin and norepinephrine activity.
- These medications are often prescribed when other antidepressants have not been effective or have caused intolerable side effects.
In conclusion, antidepressants work by targeting neurotransmitters in the brain to regulate mood and alleviate symptoms of depression. It's important to work closely with a healthcare provider to find the right medication and dosage that works best for each individual.