In May 2013, my son (D) had his second anaphylactic reaction. This happened within 20 minutes of us arriving at a friend’s house for a playdate. After running around the garden with his friend, D stopped so I could apply some sun tan lotion and to have a snack (a biscuit and two baby crisps). He immediately developed a rash and two hives appeared on his neck. He swallowed a spoonful of anti-histamine medicine hard and then became extremely upset. His tongue looked swollen, the rash was now on his chest and then he began coughing. I gave him his EpiPen (and then his inhaler) and the coughing stopped. He was kept in hospital overnight but fortunately there was no second wave of reaction.
On the one hand, this reaction showed us how quickly the EpiPen takes effect and stops a reaction in its tracks. This is some comfort, given the first time round, he had to spend a week in hospital, of which four days were in intensive care. That first reaction was how we discovered his peanut allergy, so we didn’t yet have our own adrenaline auto-injector at that point. Although the paramedics arrived incredibly quickly, there was still a 10-15 minute time lag between anaphylaxis starting and him receiving adrenaline. So, it was reassuring to see how effective the EpiPen can be.
However, on the other hand, the second reaction was maddening as the cause was unclear. First time round, peanut was the obvious culprit. Second time, the cause could be one or a combination of something in the garden or something in the sun tan lotion, crisps or biscuits.
Our doctors skin prick tested D for a variety of environmental allergies and he came up allergic to grass, cat, dog and house dust mite. They then set about arranging a series of “challenges” in hospital, to check whether the sun tan lotion, crisps and biscuits played a part.
Sun tan lotion challenge
So what happens at a sun tan lotion challenge appointment? Well, the first time for us, nothing; as I had cleverly forgotten to stop giving D his daily dose of anti-histamine five days beforehand! The appointment had been arranged in a flurry following the mystery reaction and there hadn’t been enough time for the hospital to send out the usual instructions paperwork before the appointment. I can safely say that, having done battle for a space in the hospital car park for no reason, it’s a mistake I won’t be making again…
At the rescheduled appointment, the allergy nurse slathered the sun tan lotion over D’s arm. We waited 30 minutes for a sign of any reaction. When no rash appeared, we were allowed to go home. So far, so good. The sun tan lotion was ruled out as a cause.
A few weeks later, we were back at the hospital again for a food challenge in respect of the baby crisps. We arrived at 9am and were there for 5 hours. The day began with D being weighed and measured and then seen by a doctor, to check he was well enough to undergo the challenge. I understand that even mild cold symptoms might mean that the challenge cannot go ahead.
Apparently, an estimated 15% of children tested do have a reaction during a food challenge. The reaction would be treated in the same way as if it happened in the outside world, so anti-histamine for a mild reaction and adrenaline for a severe reaction.
For the first two hours we had to stay on the children’s ward. I hadn’t been relishing the prospect of making D sit in a bed for two hours, but luckily as the “sats” monitor was stuck to his toe and kept in place by his sock, he could move around and stand up and play next to the bed.
Every 15 minutes, the allergy nurse came to take his obs and give him increasing amounts of the crisp. We started with a crumb and ended up with him wolfing down half a bowlful on the final dose. After the first couple of doses, D figured out the procedure and was helpfully commanding “more crisps now” as soon as his obs had been taken. After the final dose, we were allowed into the playroom (the highlight of the day for D), with a nurse checking his obs every so often over a two hour period.
When that two hours passed without incident, we were allowed home. I was warned about the slim chance of a second wave of reaction and given the telephone number for the ward, so I could let them know about even any mild symptoms which appeared overnight.
Luckily there was no secondary reaction and we will be returning to the hospital soon for the final challenge in respect of the biscuits.
Some points to consider
If you are attending your first hospital food challenge soon, here are some things you might want to think about:
- Are are you clear about what medications you need to stop before the challenge? We had to stop giving D his anti-histamine (loratadine) five days beforehand. We were told to continue giving him his daily preventer inhaler and montelukast and using his eczema creams.
- Do you need to bring in the challenge food?
- Do you know what happens about other meals? D had his usual breakfast before going to hospital and I was asked to bring in a packed lunch (for both of us) for after the challenge.
- Remember some toys and books (or for older children, iPods and the like) – you will be there for several hours, even if the challenge goes smoothly.
Further resources on food challenges
For more information on food challenges, see:
- Allergy UK, Allergy Challenge.
- Anaphylaxis Campaign, Food challenges as a way of testing for food allergies.
- East Cheshire NHS leaflet, Food Challenges.