Some key differences here: sertraline (Zoloft) is an SSRI, an antidepressant. This you take daily and it blocks the re-uptake of serotonin in your brain, increasing the serotonin. Fluoxetine is also an SSRI. Xanax is a benzodiazepine, a CNS depressant. The main difference is SSRIs you take daily and help with depression symptoms and Xanax and other benzos are usually used as needed for panic/ anxiety symptoms to calm your nervous system Propranolol is a beta blocker, other beta blockers are used for heart issues. With the correct dose and timing, propranolol helps control palpitations (that can stem from anxiety). Please let me know if this helps or if I can try to explain better