Brief Answer:
They will help with clausterphobia

Detailed Answer:
Hello,

Thanks for posting on XXXXXXX

Both medications are antianxiety drugs and unless your clausterphobia is severe, I do not see the need to take both medications at ones especially when the interaction between tranxene (clorazepate) and xanax (alprazolam) increase sedation. So if you are taking both, your level of sedation can be increased two fold. It is best to take just one, say xanax then hold on and see how you feel.
Also note that both medications are prescription only and taking it without a doctor's advise is not recommended. I suggest you discuss with the physician responsible for the MRI about your clausterphobic condition and see if he/she can help before you get into the machine.

Hope this helps and wish you the best.
Dr. Nsah

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