How long can she go on with this pain in her arm?

I am so sorry for your mom.
I recently wrote a couple of newspaper columns on shingles and got a whopping number of response about the pain from people of all ages.
The long-term effects for some people - even younger people - can be horrible. Even if long-term neurological damage isn't done to your mother, her current pain is debilitating.
Shingles isn't life threatening in itself (or seldom is), but many find an attack unbearable they wish it was. I would talk to your doctor about hospice care. If your mother, at 97, isn't eating or drinking because of pain, it's likely she would qualify.
Your love for her is the reason you are looking for pain control for her. This is horrible for you to watch. Hospice is there to ensure the best quality of life a person can have. It's possible that they can relieve her pain enough for her to eat and drink, therefore keeping her alive longer. Please, also, if you take advantage of hospice (with her doctor's help), consider taking advantage of their chaplain for your own comfort.
Take care,
Carol

I am so sorry for you and your mom and I can't offer any advice, but you and your mom have a prayer coming from me and mine.

My mother also had shingles in her mid eighties and her pain and discomfort were terrible. I did research and found that sometimes Wellbutrin, an anti depressant provides significant relief. It did help her. Also Lyrica helps with neurologic pain. I know how terrilbe it is to see your mom suffer this way........I will pray for you both. My mother's bout with shingles inspired me to get a shingles vaccine.

Cardia, it might sound a little unconventional but when I had shingles - under my breasts and around to my back, I stayed in the bathtub for hours just soaking and it did give me relief from the pain. Obviously with your mom being frail that wouldn't be an option for her but maybe if you are able to keep her arm in water somehow it might help a bit. I'm guessing she is bed-ridden so maybe a little plastic blow up pool or baby bath of some type would allow her to keep her arm soaking and you could keep adding warm water.

I feel so bad for you, I know I couldn't stand it when my mom was suffering with some problems. It's so difficult to see our Mom's in pain. I will pray that your mom gets quick relief from her pain. God Bless!

I think Palliative Care is the best option rather than Hospice for these reason:
Palliative care (pronounced pal-lee-uh-tiv) is specialized medical care for people with serious illnesses. It is focused on providing patients with relief from the symptoms, pain, and stress of a serious illness—whatever the diagnosis. Palliative care is provided by a team of doctors, nurses, and other specialists who work together with a patient's other doctors to provide an extra layer of support. It is appropriate at any age and at any stage in a serious illness and can be provided along with curative treatment. Palliative care relieves the symptoms of these diseases, such as pain, shortness of breath, fatigue, constipation, nausea, loss of appetite and difficulty sleeping. It helps you gain the strength to carry on with daily life. There are no time restrictions. Palliative care can be received by patients at any time, at any stage of illness whether it be terminal or not. Try to find a Palliative Care program that includes Outpatient treatment most palliative care is for inpatient care.


Hospice:
You must generally be considered to be terminal or within six months of death to be eligible for most hospice programs or to receive hospice benefits from your insurance.

My mother is almost 92 and had shingles on her forehead 5 years ago. Unfortunately it went into the post herpetic nerve pain and it took many different doctors and medications, narcotics & shots for over 2 years to get the pain where she can at least tolerate it. The medications she is now on for this after shingle pain (5 yrs later) is the Fentenyl patch 50 mcg/h replaced every 72 hours, gabapentin 300mg (1 every nite), and Lidocaine 5% Ointment (this is applied directly to the forehead very carefully to numb the area and she is now on an anti-depressant Citalopram. It is very sad to see them go thru all this knowing now that this horrible pain is probably here to stay. But at least she is able to tolerate it a little better now. Hope this helps.

I had shingles pain that affected my forehead and hair earlier this summer. I used Infrared light by Anodyne Therapy. I treated my painful areas for 20 to 30 minutes 2 times per day for about 5 days and obtained remarkable results. I am no longer in pain. I was able to avoid a witch's brew of medications that would have slowly poisoned me. Look into this product called Anodyne Therapy. It is "infrared light" It great for reducing swelling and pain and other things as well. Some PT clinics and in house therapy services us it. Be informed in advance that it is not paid for by most insurance companies. Most insurance providers consider it" Experimental" when in fact it is not. It has been widely used all over the world. Research it on PubMed.gov It has been used more frequently because it is more holistic and non-intrusive. It will not interfere with other medications since it is a vasodilator. That is why it will decease the pain that she is experiencing. A lot of medical professionals will offer to increase her pain medications without trying something less intrusive . With what little quality time you have I would try to keep her quality of life and her mental awareness and her pain at a minimum. Increasing medications may not be the answer. The results I received were very quick and decisive. Check it out before you explore hospice or other venues.

As another answer suggested unless your mother has a terminal disease she may not qualify for hospice care but call them in all the same. Many also offer palliative care and they are experts in pain management both from a traditional and holistic perspective. At least as importantly they have support for the caregiver from trained professionals.
Unfortunately the post neuropathic pain from shingles may never go away At the first sign of an attack, usually red spots quickly turning to blisters it is important to start anti viral medication immediately. Call your drs office and if they won't give you an appointment that day go there and make a nuisance of your self till someone sees you. This is not widely known but most practices have someone on call when the office is closed. Call the office and you should be connected to an answering service You can also call your local hospital and they may be able to put you in touch with a Dr. Go to the ER if necessary or a walk in clinic if you have one BUT start treatment at once. Usually shingles appears on the lower rib cage radiating round to the back ,however it can appear round the eye and the ER is the only option because the patient will need to be hospitalized because there is a danger of loosing the sight in that eye and the pain is excrutiating.
As far as the shingles vacine is concerned, anyone who has had chicken pox should get it. Even if you already have had shingles it is still advisable. Until recently there has been a shortage of the vacine but it is now readily available but may be expensive as there can be a high co-pay.
Topical applications can help, ice packs, antibiotic cream when the blisters break,local anesthetic sprays and liquids. I would cautions against capsazin because it can cause a very severe burning sensation. Wear loose light clothing preferably cotton close to the skin and women will find it more comfortable to go without a bra if practicle. The use of neurontin seems to be quite helful but may make some people very sleepy.
My thoughts and prayers are with you and your mother. Continue to give the pain medication as directed even if it makes her sleepy at least she is comfortable.Request a higher dose or a change to a long acting medication if the pain is not controled. Do not be tempted to give her extra pills on your own because the mid level narcotics contain Tylenol and too much will cause kidney damage. A fentenyl patch may be the answer because that does not cause digestive upsets which could be the reason for not eating. Protein drinks and a light soft diet are the right choice even baby food may be tolerated. Care of the bowels is very important. A nightly stool softener will make a bowel movement more comfortable. Above all do not let her become constipated from the pain meds because this will only add to her discomfort and reluctance to eat. Attention to personal hygiene is also important as is changing position in bed or short periods out of bed possibly in a recliner. It is also not true that hospice can give your mother stronger medication. The hospice nurses are experts in pain management and can make recomendations to your mother's Dr but he has the final say

I agree, call in Hospice. When my mom had hospice, they bent over backwards to help her manage her pain. And if you end up with a nurse you don't like, ask for a different one. Not all nurses mesh with every family. Life is too short,( literally for your mom), so find a hospice nurse that you all like. We went through the private sector for hospice too.

we have our grandma here,. and she has shingles ,. the blisters are gone,. pretty much. and we got her on the shingle pills within 48 hrs of onset. which i think helped alot. but now she is beginning to experience severe pain .. we have the generic brand for nuerontin.. and that seems to be helping , although she is going to be 99 yrs old on feb 17th. its surely is sad to see her in so much pain.. wish their was more we could do for her. terrible that someone so old has to deal with this...