One of our rescue girls arrived with localized demodex mange. We didn't wait to treat, just started with Goodwinol ointment and used an omega-3/omega-6 oil supplement to boost her immune system. The oil we used was lipiderm, but any omega-6 supplement will bolster the immune system.
If your vet thinks it's okay to wait a bit before treatment it could be that he didn't find enough mites to confirm mange (it's normal for pups to get the mites from their dams, but unless they get out of hand the mites are usually not a problem). Just watch the spots closely for in increase in size (measure them with a ruler now so you'll have a base size) or for additional spots popping up. If the spots grow or if you see more develop, I'd talk to your vet and get a topical treatment right away to prevent it from getting more serious.
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"It's not what you gather, but what you scatter that tells what kind of life you have lived!"
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