Brief Answer:
It can be done in following manner

Detailed Answer:
Hello,
Thanks for using Healthcaremagic.

I read your query and understand your concerns.

There are two approaches for smooth transition from one antidepressant to another antidepressant. One is adding new medication slowly and once the target dose is build upon the existing medication can be tapered down slowly. In other words up titration of new medication followed by down titration of existing medication.

The second approach is simultaneous up-titration of new medication and down titration of older medication. This approach takes less time in compare to above approach although there is risk of worsening of symptoms.

I feel the first approach is better one and I often go in following manner for most of my patients

First week
Pristiq 25 mg and Lexapro 2.5 mg

Second week (Day 8 onwards)
Pristiq 25 mg and Lexapro 5 mg

Third week (Day 15 onwards)
Pristiq 25 mg and Lexapro 7.5 mg

Fourth week (Day 22 day onwards)
Pristiq 12.5 mg half tablet and Lexapro 10 mg

Fifth week
Lexapro 10 mg

I hope this answers you.
Feel free to write back to me if you have more questions.
Thanks and regards.

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