I have not tried a B12 patch, so I can't comment on that. I think the B12 which you get from an oral multivitamin is going have almost no effect. The B12 doses in multivitamins are generally far too low, and also very little B12 gets absorbed in the stomach. With ME/CFS and/or peripheral neuropathy, you need megadoses of B12, far higher than the amounts of B12 you would take for your normal recommended daily nutritional allowance. Ideally, B12 injections are the way to go. Injection doses of around 1,000 mcg (= 1 mg) or higher are typical. WIth injections you get the benefit of the full 100% dose that is injected. Well, that is not strictly true, as some of the B12 may be washed out, because you have taken this high dose. One place that sells B12 methylcobalamin for injection is here. B12 hydroxocobalamin injectables can be bought here. Under optimum conditions, with B12 sublingual tablets (and probably skin patches too), only around 5% of the B12 will get into your body. So you have to take much higher doses, to compensate for the fact that you are losing 95% of your B12. For B12 sublingual tablets, I would say that you need to take at least 5000 mcg daily. I found this webpage of sellers of high dose B12 methylcobalamin tablets in Australia. Though I have to say the prices in Australia seem much higher. It may be cheaper for you to buy B12 from the US or UK , even with international postage.