Although diazepam is a controlled substance, we do not worry about addiction and withdrawal in animals as long as it is given in moderation and as prescribed. I am careful about giving this medication to geriatric patients, so make sure that you monitor him carefully for any adverse reactions such as respiratory depression or behavior changes.
I tend to prefer alprazolam for this purpose in my patients.
As long as it is being given just on an as needed basis and not regularly, you have no concerns about tapering, etc.
I hope that helps.
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