Brief Answer:
post-zoster pain

Detailed Answer:
Hi

Post-zoster pain does not cause leg edema which is always a condition that needs addressing. Non-steroidal anti-inflammatories are not considered an appropriate or useful medicine for zoster pain and cause fluid retention if not outright kidney failure. Anyone with leg edema needs the cause addressed fairly urgently to look for kidney failure, heart/lung/liver failure or just obesity and varicose veins. I cannot say in your particular case, but my bias is the voltaren but I wouldn't be surprised about other serious conditions... severe emphysema being a very common one.
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Then, the most essential feature of zoster pain is that historically it created the entire field of neuropathic pain--largely because it has the highest success rate in its treatment. Literally EVERY nerve pill is better than 50/50 likely to majorly lower pain:
novocain/lidocaine--lidocaine patch, amitryptiline has lidocaine like effects, many arrhythmia medications also have lidocaine like effects

Spinal drugs that lower spinal nerve activity--amitryptiline again which is very cheap and at the doses used for this, really safe too, but any of the older antidepressants. Cymbalta is a newer one also effective that was basically a way to make more money when older generics are probably stronger.

Anti-epileptic drugs: gabapentin is very effective and again, quite safe, and fairly inexpensive compared to lyrica which is a pretty good drug working by slightly different methods and pretty safe, it is the only one in the entire list that has regulations (mild ones) for some addictive potential (that I personally have never seen any addicts or abusers or street use with lyrica, ever) also all the other ones .. dilantin, valproic acid, probalby others

Nerve killers: hot chili oil, there is a prescription form of it called cathepsin, it activates and kills off the pain nerves. you get tolerant to hot foods.. same effect. It's pretty good in the literature, almost never used because obviously it hurts and it is pretty far down on a very long list of effective medications as we see. Also surgical treatment but since zoster is due to an injured nerve, surgery is just more of the same and is basically never used.

In someone with fibromyalgia who actually has something else that is really wrong with them (like zoster, disk disease, actively bleeding wounds, etc.) those other conditions get the person's attention more than the zoster and treating those first is the first step.

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