Following the helpful advice on this forum, I started taking sublingual B12 last summer to help with my peripheral neuropathy (which I had since having chemotherapy for breast cancer 4 years ago) and to help generally with levo absorption. I had a TT about 10 years ago. The first batch of Jarrow 5000mcg tablets were as expected - they dissolved easily under the tongue. I bought another batch around the end of November but these don't seem to dissolve but need to be crunched. They appeared to be the same as the initial batch.
I've looked at the Jarrow site and they do say that the last modification was June 2013 but I can't see any more information.
Has anyone else noticed a difference?