Is it ok to take 2mg of Dilaudid and 2mg of valium together for postherpetic neuralgia (shingles) pain or is there something better?

Be cautious. Although you are using low dose of both drugs, better not to combine them. For post heretic neuralgia, gabapentin can be more effective, unless there is a contraindication, ask your doctor about. Good that you asked, always exercise caution with multiple medications .