An Author's Guide to Allergic Reactions

It can be quite a terrifying and life-changing experience, finding out that you're allergic to something. Maybe not if you just end up with a rash or can't stop sneezing, but more so if you go into some sort of shock. When I was 17, I discovered (the hard way) that I’m allergic to a particular antibiotic, and I can honestly say the experience changed the way I live my life.


In the context of storytelling, allergic reactions are actually great and uncommon ways to introduce obstacles for your characters to overcome. They can be pre-existing or a surprise. They can be mild, or they can be severe. They can affect any body part you want and can even kill.They are also something that makes your character vulnerable that they physically cannot change about themselves. Therefore, there will always be an element of risk in their story.


In this post, I’ll be talking about the different types of allergic reactions, how symptoms present themselves, and also how you can use them in your stories.

Pre-existing Allergies

These are allergies that your character knows they have. It is important to note that giving your character a known allergy can affect the plot, not in that they will have a reaction, but in that they might.They may be unwilling to go places, do activities, or eat foods for fear of a reaction. In severe cases, just the possibility of a reaction could change the direction of your plot.


Consider your character is at a crossroad; they can either take a shortcut through a field of poppies, or they can scale a precarious cliff face. The catch is: they’re deathly allergic to those poppies. What should be an easy decision is suddenly made much harder.


If you give your character a known allergy, also consider that they may carry medication. Medication can run out, go missing, be stolen and be tampered with.

Skin Reactions

When somebody touches or consumes something they’re allergic to, skin reactions are very common. If your characters are in a forest, for example, they may likely leave with a reaction of this sort due to brushing against plants.


Skin reactions are great ways to introduce non-life-threatening obstacles or inconveniences for your character. For example, give them a rash before an important event, such as a date or a job interview.


Third-person characters will see:

  • Raised, red, blotchy skin (hives).

  • Dry, red, cracked and peeling skin (eczema).

  • Other types of rashes, (if writing fantasy, you can even make something up!)

  • Symptoms may be localised to the area touched, or if the item was ingested, the symptoms may be global, across the entire body.

First-person characters will feel:

  • Severe itchiness, like thousands of ants crawling over the area. When scratched too harshly, characters may draw blood and will undoubtedly make things worse.

  • Sore and burning skin that feels hot.

  • Skin sensitive to touch. Light brushes may feel like knives gliding over the flesh.

Allergic Rhinitis

This type of allergic reaction is extremely common. You’ll know it from hay fever symptoms and pet danger allergies. These symptoms often come in conjunction with conjunctivitis and sinusitis. Mild reactions can often be mistaken as the onset of a cold. Allergic rhinitis can leave you feeling lethargic unmotivated, and generally quite crabby!


Third-person characters will see:

  • Characters may sneeze or cough frequently.

  • They may carry tissues and sniff through a blocked or runny nose.

  • Red, swollen, watering eyes.

  • The character’s voice may sound nasal.

First-person characters will feel:

  • Pressure in the sinuses, like their head is filled with cotton wool.

  • Blocked nose and difficulty breathing. This can make things like eating and exercising exhausting.

  • If a character is suffering from conjunctivitis, their eyes will feel itchy and potentially will burn. Swelling may make it difficult to see or open their eyes (especially after sleep).

  • In severe cases, characters may suffer from asthma. In which case, your character will feel tightness in their chest, preventing the ability to breathe out, which leads to coughing. They will feel their airways and chest constrict, which leads to laboured breathing and wheezing. Some sufferers have described the feeling as like hyperventilating through a straw.

Abdominal Reactions

This is the first in the series of serious reactions, most often caused by ingesting something. This makes food allergies a great thing to make your villain privy to. Allow them to lace your main character’s food in order to delay their attempts to thwart the villain in achieving their goal. Symptoms include:

  • Abdominal cramping or pain. This may come in waves that get progressively worse and can be debilitating for a character—especially if they are on a journey.

  • Nausea or vomiting, which is particularly risky if your character is low on food. The loss of nutrients can be particularly bad for their nourishment.

  • Diarrhoea, which can very quickly lead to dehydration. Once a character is dehydrated, they can experience confusion (in the form of hallucinations, or even just the inability to process thoughts), weakness, fainting and death.

As you can expect, these reactions can be easily mistaken for food poisoning, which means many people will continue to consume the food and inevitably make things worse.

Anaphylaxis

Anaphylaxis is probably one of the deadliest and terrifying allergic reactions if help isn’t found and medication administered. Some people can be so sensitive to triggers that just breathing in a few particles can lead to anaphylactic shock. Anaphylaxis can start with—or accompany—any of the symptoms already mentioned and usually begins within a few minutes of coming into contact with the trigger.


Really up the tension by delaying help to treat your character’s anaphylaxis. They may have a reaction in the middle nowhere, while they’re alone, or perhaps their medication is missing for whatever reason.


Third-person characters will see:

  • Swelling of the face and neck.

  • The character may begin shaking or shivering. If they panic, they may hyperventilate.

  • Blue skin or lips once oxygen deprivation takes hold.

First-person characters will feel:

  • Many sufferers recall the beginning of anaphylaxis resembling a tickle in the throat that doesn’t disappear when they try to clear it.

  • Tightness in the chest and throat that makes breathing difficult.

  • Anxiety, which can lead to panicking. Think wide eyes, racing pulse, rushing thoughts (confusion, fear), rapid and shallow breathing.

  • Eventually, the character will feel light-headed and dizzy. They may even faint. If this happens, allow your narration to signify this (especially if writing in first person); simplify your sentence structure and be less and less detailed.

And there you have it; multiple ways to ruin your character’s lives by taking advantage of their allergies! 😉