These fuzzy creatures might look cute and harmless, but in fact they pack a big punch.

The venomous puss caterpillar appears to be back in Florida for its seasonal return.

A Florida woman documented her scary and painful encounter on Facebook.

Bri Oteri was in Dade City, Florida, said in the post she leaned against a wooden fence and felt her wrist start to burn after coming in contact with the puss caterpillar.

Oteri said, “It felt like fire ants in that moment. I looked down and saw this fuzzy thing moving across the wood.”

The woman was checked out by an EMT but symptoms increased later in the day and her husband took her to the ER.

“I was watching my son practice and all of a sudden I couldn’t breathe. I thought I was going to pass out, and then came the pain. In my chest.. in my entire right arm, radiating from my wrist all throughout my arm and shoulder,” Oteri said. “The pain was so excruciating I was hysterically crying in the hospital pleading for the doctors and nurses to help me. Morphine didn’t even touch the pain.”

A 2014 report by National Geographic said the caterpillars are the most venomous of their kind in the U.S. and that their “soft, outer comb-over hides small, extremely toxic spines that stick in your skin.”

Oteri warned others to be on the lookout for these painful creatures.