Generalized weakness is one of the most common adverse effects of taking mirtazapine, and it usually takes 10-20h to recover after a single dose, depending on the individual.
Mirtazapine belongs to the noradrenergic and specific 5-hydroxytryptamine antidepressant (NaSSA), and also has a blocking effect on 5-HT2 and H1 receptors. So in addition to its antidepressant effects, mirtazapine has good sedative and anxiolytic effects. This sedative effect is the main reason for the generalized weakness of the person taking the drug.
Mirtazapine is a small molecule, easy to cross the blood-brain barrier, the half-life is 20-40 h. Therefore, the duration of the drug effect after taking the drug is longer.
In summary, it is recommended to take the drug at night before going to bed, after 8~10h of sleep, the drug is gradually metabolized, and the side effects of generalized fatigue will be reduced accordingly. In addition, if daytime activities are seriously affected by fatigue and drowsiness, it is recommended to seek medical advice as soon as possible and consider whether to change the drug after communicating with the physician.