Paxil is an antidepressant that blocks the enzyme that breaks down serotonin
and targets serotonin to only certain
receptors while bypassing others, allowing serotonin to wash longer in the receptors. Xanax is a benzodiazepine, an anti-anxiety and anti-seizure medication that targets GABA receptors. Benzos act only for a short time, some longer, some shorter, while antidepressants work all day while you're on them.