Can you ingest cinamon essential oil?

The essential oil of obtained from the cinnamon leaf is relatively non-toxic. I may be ingested in small amounts.

The essential oil obtained from the cinnamon bark is a dermal toxin, irritant and sensitizer; it also irritates mucous membranes.

Both forms are commonly used and in small diluted doses may be ingested, however it is advisable to test for Allergies before using much. I personally know several people who have an allergic reaction to cinnamon even in very small doses.