Hives (Urticaria): What Canadians Should Know for First Aid and Workplace Safety

Hives—medically known as urticaria—are raised, itchy welts that can appear suddenly on the skin. Many Canadians assume hives are always caused by food allergies or products like soap or detergent. While allergies can be a trigger, hives are often linked to other causes, including infections, stress, medications, and underlying health conditions.

From a first aid and workplace safety perspective, hives are important because they can sometimes signal a more serious allergic reaction or develop alongside breathing difficulties. This article focuses on recognition, risk awareness, and when to seek help, not medical diagnosis.

Why Hives Matter in First Aid and Safety Settings

In first aid and CPR training, hives are treated as a warning sign, especially when they appear suddenly or alongside other symptoms.

Hives may occur:

At work after exposure to chemicals, medications, or stress
At school or daycare following illness or infection
At home after food exposure or medication use
During physical or emotional stress

In rare cases, hives can occur as part of a severe allergic reaction (anaphylaxis), which is a medical emergency requiring immediate action.

Acute vs. Chronic Hives: Why Duration Matters

Understanding how long hives last helps guide first aid decisions.

Acute hives: last less than 6 weeks
Chronic hives: last longer than 6 weeks or recur frequently

Acute hives are more likely to be linked to recent exposures, while chronic hives often have non-allergic causes.

Common Causes Relevant to First Aid Situations

Allergic Reactions

Allergies are a well-known cause of acute hives, especially reactions to:

Foods
Medications

Food-related hives usually appear within minutes to a few hours. Medication-related hives may develop after the first dose or after days or weeks of use.

First aid relevance:
If hives are accompanied by difficulty breathing, swelling of the lips or throat, dizziness, or collapse, activate emergency response and follow anaphylaxis protocols immediately.

Viral and Bacterial Infections

Infections are one of the most common causes of hives, particularly in children.

Hives may appear:

During a cold or flu
After a viral illness
With infections such as strep throat or urinary tract infections

Workplace and school relevance:
Hives may appear even when the person does not feel very sick, making recognition important for supervisors, teachers, and first aiders.

Stress and Physical Strain

Stress is a shared trigger for both acute and chronic hives.

Examples include:

Heavy workloads
Shift work
Emotional stress
Physical exhaustion

The body may react even if the person does not feel consciously stressed.

Safety relevance:
Stress-related hives are common in high-demand workplaces and may worsen existing skin or allergic conditions.

Chronic Health Conditions and Medications

Chronic hives may be linked to:

Thyroid disorders
Autoimmune conditions
Liver or kidney disease

Certain medications—especially non-steroidal anti-inflammatory drugs (NSAIDs)—can trigger or worsen hives.

First aid relevance:
Persistent hives should be documented and referred for medical assessment, especially if they interfere with work or daily activities.

When Hives Become a First Aid Emergency

Immediate medical help is needed if hives occur with:

Difficulty breathing or swallowing
Swelling of the face, lips, tongue, or throat
Dizziness or fainting
Rapid worsening of symptoms

These signs may indicate anaphylaxis, which requires urgent care and rapid use of emergency response protocols.

Practical Safety Awareness for Canadians

Not all hives are allergies, but all sudden hives should be taken seriously
First aiders should monitor for breathing or circulation issues
Workplaces should have clear emergency response plans
Training helps ensure early recognition and proper action

Understanding hives improves preparedness in homes, schools, and Canadian workplaces.

Educational Note

This article is provided for general education and safety awareness only. It is not intended to diagnose or treat medical conditions. Anyone experiencing severe or persistent hives should seek professional medical care.