Lychee: Safe for Dogs and Cats?

Only a little ripe lychee flesh is potentially shareable; unripe fruit, skin, the large seed, canned syrup, and the fruit's high sugar make lychee a poor routine treat.

Lychee is not a useful cat treat. Unripe fruit can be hazardous, the skin and large seed are unsafe, and even ripe flesh is sugary and should be avoided or kept to a tiny accidental taste.