It depends on how the antidepressant works and the person. If they target the same neurotransmitters, such as serotonin, then generally no, you can't take more than one. Taking several drugs at once often works better than taking just one, provided each one is working but just not well enough -- you don't add on to a drug that isn't doing anything. No purpose. Just more side effects to deal with. Your psychiatrist who is prescribing all this should know this, and you can research these drugs on your own and look up the contraindications and drug interactions -- there are many good websites for this information if you Google the drugs. You can also ask your pharmacist. Given you say you're crying every day, and terribly sad all the time, it doesn't seem any of them is working. Have you discussed this possibility with your psychiatrist?