We didn't take DS to the doctor when he had HFM. However, his symptoms were quite mild - fever that broke in one night, a few sores on his hand and maybe a couple in his mouth - and we were fairly certain that it was HFM because there was a notice at daycare that it was going around. Partially, I think his course was mild because I was still nursing him. He was around 11 months.
Here is some information that I compiled for myself and another mom at daycare that fall that it broke out. I'm copying it to you here. Take what you want and leave the rest. You may already know some of this stuff. The XXX is where I had typed the child's name. The mom I originally sent it to had a 2-year-old who had an awful case. They didn't know what it was (maybe it happened before the notice went up at daycare?). The child's mouth was completely filled with sores; her throat was closing up and they rushed her to the Children's Hospital in the city an hour away in the ambulance (after the parents took her to the local hospital and they didn't like the looks of it). She didn't eat for almost a week.
1. Coxsackie is a virus that provides immunity once exposed. So, if you were exposed as a child, chances are you won't get it now as adults, or XXX won't get it again. (or, if you/she did get it again, the course would be mild). However, hand, foot, and mouth is a syndrome and can be caused by a number of viruses, coxsackie is just the most popular. It would be possible to be immune to coxasackie, but if the HFM is caused by one of the other viruses, you could come down with it, too. Outbreaks are more likely in the early fall, and it is highly contagious.
2. Can she rinse or gargle? Have her gargle with warm salt water (made with sea salt, if you have it). I think 1/2 - 1, tsp in 1 c of water is the right dosage. (For years, whenever I had a sore throat, I would make the strongest possible solution and then wonder why it didn't feel that great. My mom, who is a nurse, got me back on the right track with the proper dosage.) It will soothe her throat and may help with the healing.
3. Not specific to the coxsackie virus, but more generally, L-lysine is a supplement that is good for viral infections. Very useful if you have canker sores, cold sores or an outbreak of herpes virus. I use it anytime I have canker sores in my mouth (or those little cracks on the side of your lips or even after eating too much acidic food). I don't know what the dosage for a small one would be. Not sure if it comes in anything other than a tablet or capsule. You can find the dosage for an adult easily by googling L-lysine and herpes. The dosage for treating herpes is much higher than the dosage that is recommended on the back of the bottle. I have taken some myself in the past 2 days, just in case I was exposed and am not immune.
4. I'm not big lover of medications for infants/children (or anyone, for that matter), but have you given her Tylenol for the pain or asked the doc for a script for Tylenol with codeine?
5. Have you thought of chamomlile tea to help her sleep? If she's REALLY having problems at night, you might consider benedryl. Again, I'm usually anti-medication, but in this case, I might cave.
This link has a suggestion for a mouth rinse/coating
http://nips.med-web.com/Handouts/Individual%20Pages/coxsackie.htm
And, I like Dr Sears stuff. He also has a suggestion for a mylanta/benedryl mix --
http://www.askdrsears.com/html/8/T082600.asp
Finally, since she has been given an antibiotic, you may want to consider getting plenty of live culture yogurt and/or kefir into her as soon as she will take it. Antibiotics wipe out good bugs in addition to the nasty ones.
And FYI to the Mothering poster - an antibiotic would be uncalled for in this case, if you are fairly certain it is a virus. But they were throwing everything at this little girl.
we are generally a very healthy bunch, so something like this is completely out of my league lol
and homemade buttermilk biscuits drizzled quite liberally with orange blossom honey. Today everyone has enjoyed a leisurely day of cartoons and good company. I've spent my day cooking for my little monsters and wiping down any surface they possibly could reach. Oh laundry too lol. I'm feeling the need to keep cleaning to keep me and their dad from catching it...I hate cleaning 
but them's the breaks right? So far everything's a little better now I know what I'm working with, and how to treat it. Thanks for the responses, I'll let you know how it turns out 
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