Brief Answer: should not be combined Detailed Answer: Dear Friend, Welcome to HCM. I am Dr Anshul Varshney. I have read your query in detail. I understand your concern. First of all if you have some stomach problem , and you are taking benadryl for it and want to take Zolpedem also for that only , I must tell you these drugs are not indicated for treatment of any stomach ailments. I would be glad to help you regarding your stomach ailments. So please give us details about that . As far as your query is concerned. These drugs should not be combined as Benadryl causes sedation and Zolpidem and Oxazepam also induces sleep. So combining them can cause excessive sedation , drowsiness , respiratory depression and chances of aspiration into lungs due to excessive sedation. So avoid combining them. I hope I am able to answer your query. If you have any further query you may please ask us. If you wish you may also discuss with us about your stomach problem. Stay Healthy.

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