Compared to similar drugs, Valium (diazepam) acts very quickly but can have interactions with other medicines. Xanax (alprazolam) effectively treats occasional. Ativan (lorazepam) and Valium (diazepam) are both used to treat anxiety disorders and other psychiatric disorders. May 6, - Is one stronger, weaker, faster acting than the others? When I asked the clmt, she indicated that the Xanax and Valium was for everyday panic.