Thanks for your reply.
Rapid heart rate during morning when you wake up is not a side effect of Mirtazapine in my view. As you are still anxious and depressed it is possible that 30 mg of Mirtazapine is now not controlling your symptoms fully.
In such cases, a simple strategy could be to either increase the dose of Mirtazapine further to 45 mg per day or adding an augmenting agent like Fluoxetine (SSRI antidepressant)to 30 mg of Mirtazapine to augment its effect by your doctor.
There is no harm in using Clonazepam .5 mg for sleep or controlling anxiety
symptoms on as and when needed basis till the above modifications are made in your treatment regime.
Just discuss with your doctor about the options I have mentioned and most likely after trying these treatment modification, you may notice a good improvement in your current symptoms of racing heart and difficulty in sleeping
at night within 7-14 days.
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