If a medicine is considered highly serotinergic would it tend to be activating or sedating?

Could be either.: In my experience, some highly serotonergic medicines can help with sleep while others tend to be activating. Prozac, lexapro, and zoloft all tend to be activating and are usually best taken in the morning, while paxil, (paroxetine) celexa, and Nefazodone tend to be sedating and are usually best taken in the evening. Specific individuals may have the opposite experience for any of these medications.

More sedating: Serotonin is the calming, balancing nerve transmitter whereas adrenaline is the arousal, upper neurotransmitter.