Theanine causes blood pressure to decrease, and should not be taken with blood pressure medication - melatonin increases blood pressure, so these two may cancel each other out in terms of blood pressure effects. read more
Melatonin plus theanine is an effective sedative agent that may also be used in low doses for relaxation purposes during waking hours. When taking this supplement during the day, some individuals have reported an inability to retain focus or concentrate on tasks. read more