With the right conditions, you can store LSD indefinitely (well, until the end of the world or similar). I've certainly managed to keep my own LSD still potent

With the right conditions, you can store LSD indefinitely (well, until the end of the world or similar). I've certainly managed to keep my own LSD still potent after ~2 years of first getting it, by storing it in a cold, dark and dry place. Some older friends have described to me finding ~5 year old LSD that still worked, but not sure I trust that.