I can understand your concerns about medications. It is not uncommon for Paxil to cause excessive sedation, which is unlikely to happen if you switch to Prozac. Like Paxil, Prozac is a Serotonin Specific Reuptake Inhibitor (SSRI), and is not structurally or chemically related to Wellbutrin. You can start Prozac the next day after your last dose of Paxil.