Hi Urs,   Yes, SSRI's can make you very sleepy, however that side effect usually goes away during the first few weeks of taking the medication. You are already taking your medication at night, which was going to be my first suggestion. I would encourage you to you talk to your prescriber about possibly trying one of the SSNRI's that are available. These affect the norepinephrine receptors in the brain, which can reduce the feeling of sleepiness some people feel when taking SSRI's.   If you are curious about the possibility of adrenal fatigue or serotonin syndrome, it has been my experience that naturopathic physicians tend to be more open to doing this kind of testing. Also, a lot of them will do neurotransmitter tests, which will show you your neurotransmitter levels. I have found that this is helpful in figuring out what medication might work best for you.   It sounds like you've already done it, but I would also encourage you to get a full physical including blood tests, to rule out any other cause of your fatigue.   Good luck!