Joanna Quinn, 41, took her 11-year-old son Aiden trick or treating near their house in Glasgow and came home with a haul of chocolate and sweets from her neighbours.
Being cautious of her son's serious nut allergy, Joanna made sure Aiden didn't accept anything that contained a trace of nuts.
But just days later, while he was was eating one of the lollipops he’d received on the night, he told his mother that his lips felt funny.
On closer inspection Joanna realised that her son’s lips were bumpy and swollen.
The allergy medication the mum gave him didn't help reduce the reaction, and instead he started to vomit.
"After calling the NHS helpline to see what I could do I quickly rushed him to A&E where he was sent to the resuscitation ward to open his airway,” Joanna explains.
While in A&E Aiden was given steroids to help his breathing and medication to counteract the allergic reaction.
Doctors continued to closely monitor the youngster for the next 24 hours.
“Once he was stable, he was moved to the children's ward where he was monitored overnight, and was finally allowed to go home when he could breathe properly and didn't feel so unwell,” she says.
Looking back on the incident Joanna believes that the lollipop stick had been in contact with nuts, which triggered Aiden's allergic reaction.
The mum-of-three is now sharing his story to raise awareness of the issue and encourage people to be more cautious of the treats they are giving out at Halloween.
“I strongly believe that there were traces of nuts on the lollipop stick, because the allergy happened instantaneously when he touched it,” Joanna explains.
“I just want Aiden's story to encourage others to be especially careful of the sweets they are giving out on Hallowe'en and be more mindful of people's potential allergies.”
Despite Aiden getting the help he needed very quickly, Joanna worries that the story may have been very different if he had not.
“If he had eaten anymore of the allergen, he would have been in serious trouble,” she said.
“Also I worry what would have happened if he was out trick or treating by himself and started eating the sweet without me being there.
“It's horrible to think of what the outcome might have been and the fact he could have died from something children enjoy doing.”
In a bid to protect her son from a further reaction, Joanna says he’s going to be staying at home this Halloween and those to come.
“I can't risk this happening again,” she says.
“It's a shame because he absolutely loves trick or treating, but unfortunately now we can't always trust the goodies being given out at other households.
"Aiden's allergies are life threatening, so if he wasn't seen as quickly who knows what the outcome could have been.”
The risk of allergies within trick or treat sweets isn’t the only warning parents are being issued this Halloween.
Experts are also urging parents to be aware of the Halloween make-up they use on little ones, after an expert explained that certain ingredients can wreak havoc with a youngster’s delicate skin, triggering itching, burning and even blisters around the eyes.
And Halloween revellers are also being advised to be cautious of scary contact lenses this year.
Experts have issued a warning about buying coloured contacts from “rogue traders”, claiming doing so could put you at risk of everything from infections and eye ulcers to severe pain and even blindness.