A seemingly innocent animal encounter in a local park turned into a harrowing ordeal for a young boy.

Six-year-old Kenzie Macrae, described as an animal lover, went to a local park to play after school on Aug. 10, and his friend spotted what he thought was a common slow worm, a non-venomous species of legless lizard native to Europe, per Kennedy News and Media. Kenzie, who is from Sutherland, Scotland, went to pet the “lizard” when it suddenly attacked him and bit his left index finger.

As it turned out, the reptile was an adder, a small, venomous snake.

Kenzie, who was in shock over the attack, ran to his grandmother’s house, across the street from the park, for help. His finger had already begun to swell and turn white.

Kenzie Macrae in the hospital.Kennedy News and Media
Kenzie was rushed to the hospital for anti-venom treatment. By that point, his whole hand and wrist had become inflamed, and he had temporarily lost function in his fingers.

“He said it was very painful. Initially, he was in shock and kind of disorientated,” recalled Kenzie’s mom, Andrea Denoon, who rushed from work to the hospital to be by her son’s side.

“Once I arrived at the hospital, his whole hand and just above his wrist had swollen up. He was struggling to bend his fingers — his whole hand was inflamed. It was massive,” Andrea, 38, said, adding, “A lot of nurses and doctors had never seen it before, especially on children.”

Kenzie Macrae’s swollen hand.Kennedy News and Media
One of Kenzie’s friends had taken a picture of the snake that bit him, which she said was “very handy” for identifying it.

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When Kenzie’s finger turned blue and the venom continued to spread up his arm, doctors administered another dose of anti-venom. They grew concerned that the 6-year-old may have gone into anaphylaxis when his heart rate and breathing levels began to drop.

The snake that bit Kenzie Macrae.Kennedy News and Media
“You can go into anaphylaxis from this anti-venom, and your organs can start shutting down,” Andrea explained. “That’s what we thought was happening because his breathing and heart rate were really low, but it was because he was in that much of a deep sleep and so tired.”

“It was very scary [when we thought his organs were shutting down]. I didn’t sleep for two days,” she continued. “It was just a constant hand-on-chest listening to his breathing and watching him the whole time.”

Kenzie Macrae with his family.Kennedy News and Media
Kenzie ultimately made a full recovery, but 11 days after going home, he was hospitalized again with serum sickness, an immune-system reaction to certain proteins in medicines, according to the Cleveland Clinic — in Kenzie’s case, his body was reacting to the anti-venom treatment. The boy was experiencing symptoms including joint inflammation and a rash.

Andrea said her son is “absolutely fine now,” and she is continuing to keep an eye on him after his ordeal.

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She wants to warn other parents of the dangers of snake bites.

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Kenzie Macrae.Kennedy News and Media
“I was massively shocked by the effect of the bite. It could’ve been a lot worse, but it’s a scary situation to be in,” she said, noting, “You don’t know how each person is going to react to it.”

As for Kenzie, Andrea said that, despite all he went through, he “has no fear of snakes, even now.”