Heads up if you fly with an emotional support animal, Alaska Airlines announced a new policy Thursday morning.

Starting May 1st, 2018, guests traveling with emotional support or psychiatric service animals will need to provide animal health and behavioral documents, along with a signed doctor’s note at least 48 hours before your flight.

"We are making these changes now based on a number of recent incidents where the inappropriate behavior of emotional support animals has impacted and even injured our employees, other guests and service animals," Ray Prentice, Alaska Airlines' director of customer advocacy said.

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This change does not apply for traditional service animals.

Earlier this month, Alaska announced changes to their carry-on bag size limit. The current limit of 24” x 17” x 10” will shrink to 22” x 14” x 9” on June 4. Alaska says the current size is larger than most other airlines, and the change allows baggage uniformity when passengers make connections with other airlines who have different requirements.

Passengers will still be allowed one carry-on bag and one personal item like a purse, briefcase, or laptop.