If you've been suffering from depression and anxiety, Zoloft may be an option for Metronidazole antibiotic you. Zoloft is a selective serotonin reuptake inhibitor (SSRI) which means it works by increasing the level of serotonin, a neurotransmitter that helps regulate mood. This medication has fewer side effects than other antidepressant medications, making it a great choice for many people suffering from depression or anxiety.