I had pretty persistent acne growing up; as I got older, it mostly went away, but I could never seem to get rid of it on my back. I've recently been investigating H2O2 therapies for a different ailment, which has proven very helpful.
One of the problems regarding treating the back, is that it is naturally difficult to reach much of it. I decided I'd try spraying 3% pharmacy H2O2 on my back after showering. I've been using food grade for internal use, but as this is an external application, there's no problem using the more commonly available kind.
I found that the spray nozzle for a liquid wrinkle remover fit the fairly small opening to a regular bottle of H2O2, and that it sprayed a very fine mist, which is perfect for this application. I noticed an improvement almost immediately... It didn't take very long to clear up most of the back. However, it took about 3 months to finally clear up a persistent area located in the middle of my upper back. The treatment can be drying, which didn't bother me, but if it is bothersome to you, I'd expect that you could apply the spray every other day instead.
Anyway, it's a real relief to have cleared up my back for the first time in over 30 years, and I feel quite certain that it will continue to be successful. I hope this will help someone as much as it has helped me.
Acne Remedies: I tried hydrogen peroxide with the assumption that it was an antiseptic that would aid in killing bacteria, infection, etc. (essentially what pimples are when inflamed). It definitely works. As others recommended, soak a cotton ball and hold for several min. For spot treatment and to avoid overdrying & light eyebrows, I use a q-tip. I will do this 2-3x's a day. If you have already squeezed or picked, the peroxide will often cause drying, flaking, or scabbing on that pimple so I recommend using baby oil on that spot (overnight). For day, I recommend Eucerin since it heals very dry skin and is non-irritating. I never realized how much dirt is still on your face, even after you thought you washed it well. Witch Hazel is a great toner, after washing. This will remove all excess dirt without overdrying.
I tried the hydrogen peroxide remedy for acne and it has been simply amazing! I was in the bath one evening and I had a bad flare up on my right cheek of probably about 5 or 6 pimples that I had popped, got out some hydrogen peroxide (I use stronger percent than 3 though) and poured a bit on to a piece of tissue paper and held it to my cheek for roughly 10 minutes. Yes it stung! But it went away quickly. The stuff literally flattened all those inflamed pimples I had which felt super smooth, I was SO relieved! I thought, hey..I'm going to try this every day! I rub the solution on my face about 3 times per day. My face is so clear now with no pimples!! I have a history of red marks left over from 10 years of acne and the HP has lightened them significantly and it's only been about a week since I've been doing it! Since it bleaches hair I thought well hey, it would probably have some effect in fading red marks too, makes sense right? If I get a breakout, I hold a soaked cotton ball to the area for a few minutes, then later on the redness is gone and the pimple is flat. I LOVE this stuff and I think all acne sufferers should try it. Works so fast!!!