Which class of medications is considered first-line for treating major depressive disorder (MDD) and persistent depressive disorder (PDD)?

Selective serotonin reuptake inhibitors (SSRIs) are the first-line treatment for major depressive disorder (MDD) and persistent depressive disorder (PDD) due to their favorable balance of efficacy and side effect profile. They are designed to increase serotonin levels in the brain, which can improve mood and alleviate depressive symptoms.

SSRIs are generally well-tolerated, making them a more accessible option for many patients. They also have a lower risk of significant side effects compared to other classes of antidepressants, such as tricyclic antidepressants (TCAs) and monoamine oxidase inhibitors (MAOIs). This tolerability leads to better adherence to treatment, which is crucial in managing long-term conditions like depression. Additionally, SSRIs have a more favorable safety profile in overdose situations compared to TCAs, which can be more dangerous due to their cardiotoxic effects.

While other classes like SNRIs (serotonin-norepinephrine reuptake inhibitors) can also be effective and may be considered if SSRIs are not suitable, SSRIs remain the primary recommendation in clinical guidelines for initial therapy in these depressive disorders.