Brief Answer:
Yes they can be taken together; mild drug interaction might be present

Detailed Answer:
Hi,
Thank you for posting your query in Healthcaremagic.com.
This is Dr. Swarnava Dattagupta answering your query.

I understand your concern.
Atarax contains hydroxyzine which is used as antiallergic as well as anxiolytic sometimes. Whereas prothiaden contains dothiepin which is used as antidepressant.
There can be some drug interactions when taken together but it is quite rare, and the effects are not very serious. One may experience increased anxiety, insomnia, mood changes etc, but it is quite uncommon.
So they can be taken together, though risk cannot be totally ruled out.
So if one has any alternatives, one can go ahead with it. Otherwise atarax and prothiaden can be taken together, provided some risk still might exist.

Hope I have answered your question.
If you have any further questions I will be happy to help.
Regards.

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