Your previous medication Prothiaden (Dosulepin) and your current medication Inosert (sertraline) belong to different classes of antidepressants. Dosulepin is an older, tricyclic antidepressant that affects multiple brain chemicals but often causes side effects like drowsiness. Sertraline is a Selective Serotonin Reuptake Inhibitor (SSRI) that specifically targets serotonin. SSRIs are modern, highly effective for both anxiety and depression, and generally much better tolerated with fewer side effects. Transitioning to sertraline is a very common and safe step, aiming to manage your anxiety more effectively and with greater comfort. Please take it as prescribed by your doctor.