A Solution for Frostbite and Dermatitis

This is the second winter in Japan that I've had frostbite on my fingers. I'll spare you photos of them, but the finger joints at the end of some fingers randomly swell up and have some minor sores. My thumbs are fine. I had no idea what it was last year. I thought my finger joints were swollen from using my hands a lot with drawing and painting. The thing is, my fingers would also randomly become super itchy. Early arthritis didn't make sense. It also didn't fit with carpal tunnel syndrome which mostly affects the base of the thumb. I was waking up with numb hands sometimes and it freaked me out a little.

I did some Googling and besides arthritis, the symptoms sort of matched chilblains or frostbite. In Japanese, it's called shimoyake (しもやけ). I didn't think that made sense either because it doesn't get that cold where I live plus I've never had it in the past.

It seems like chilblains is common in children on the fingers, toes, and ears. (Leave it to me to have all the child-like health issues.)

When I heard an acquaintance say she had it and noticed her hands looked similar, I resolved that it was frostbite. But then I had no idea what to do about it. It's not something I've had before living in Japan and I didn't know there was anything we could do, other than wear gloves and try to stay warm.

At this point I think mine is caused by not being outdoors in the cold, but by doing food prep and washing my hands in cold water.

Last week my student noticed my hands and asked if it hurt. She said her daughter gets frostbite sometimes and recommended a medicine. She told me that most Japanese people use a product called Oronine (オロナイン) for frostbite. It's an ointment sold in a variety of sizes. She told me we can put it on anytime, but especially when our hands get itchy.

I did a quick price check and the local super-drug is cheaper compared with Amazon, where it seems they only sell the 100 gram size. 

It's convenient that the uses are listed in English also. I also tend to get the chapped skin (ひび) and atopic dermatitis (アトピー) on my hands, so it looks helpful.

Have you tried this or another ointment for frostbite or similar conditions? I'm interested to hear how it worked.

Edit: After using Oronine one time on a spot where I'd had atopic dermatitis for months, it helped so much. I had both a rough and itchy spot on my finger plus a new patch of bumps on the side of the finger. I applied the ointment (small tube) before going to bed and the new bumps were gone in the morning plus the itchy patch became smoother and the itchiness went away. 

I will be depending on this in the winter months if I get frostbite again!