I bought cupric chloride, which is more expensive than cupric sulphate, because I read a patent where the author claimed that it was not just more bioavailable than the sulphate (105%), but that it didn't react to the vitamins and other nutrients in the mix compromising them. He also claimed it was more tasteless than copper sulphate which is yuck.... which it isn't.:) It still has a distinct copper taste and a little of the bitterness.
I put it in my tea generously - too generously. It's taken me 4 days to dull the flavour by adding fresh tea to the mix constantly.
The first thing was a bit of dizziness within a half hour of taking it, which happened again the next day for a little longer when I was out in the sun. But it disappeared after that. The main thing I've noticed by way of reaction was the second day when I felt a burning pain in the middle of my foot and then in the palm of the same side. Both disappeared in 15 minutes or so. The next thing was that I was slightly gassy, burping a bit for an evening the second day and the fourth day, but that was all.
All my fears of it being corrosive (from the FDA and other netsites) and harmful, changing the serum copper levels, etc. were just a bunch of hoopla. It's probably best given after the full moon, not as much as I took, and before the last quarter, because this is when they've drawn it the most - but dogs draw copper in homeopathy all the time, just like magnesium, so it should be fine to give it more regularly.
I want to add it to the magnesium chloride and zinc sulphate so that there's a balance of nutrients for liver function. I'm trying to buy zinc chloride so that the sulphate and chloride don't react.