Why
The flesh isn't toxic, but the seeds can block the small intestine. Tannins in unripe, astringent persimmons plus lots of fiber can cause constipation or indigestion, and rarely they clump into a mass in the stomach (a bezoar). Dried persimmons and very ripe soft persimmons are extremely sugary and can cause weight gain or diarrhea.
How to give it / if eaten
Choose a ripe persimmon, remove the skin, seeds and stem, and cut into small pieces. One or two pieces is enough for a small dog; keep treats under 10% of daily calories. Dried persimmon is best skipped or given in tiny bits.
Watch for these signs
Overeating can cause constipation, diarrhea, vomiting or bloating. Swallowed seeds may lead to repeated vomiting, loss of appetite, no stool and a painful belly.
FAQ
Can my dog eat dried persimmons (gotgam)?
Dried persimmons are very sugary and chewy enough to choke on. Give only a tiny seedless piece or two, or offer a little fresh persimmon instead.
My dog swallowed persimmon seeds.
One or two may pass, but they can block a small dog's intestines. Watch for vomiting and stool changes over a few days and see a vet if anything seems off.
General information only. Weight, age and health conditions change how a pet reacts, so ask your vet if you are worried.