FLORA’S KISS BLOG

Cold Comfort: Understanding Cold Urticaria

When a cool breeze, a swim, or an iced drink turns into a medical emergency — and why this rare allergic condition deserves to be taken seriously

For most people, a cold ocean swim, a frosty drink, or a chilly morning is simply uncomfortable. For someone with cold urticaria, the same moment can bring on burning, swelling hives within minutes — and in a meaningful minority of cases, a genuine anaphylactic emergency. Cold urticaria is a real, diagnosable, and manageable condition, but it is also frequently underestimated, both by the people living with it and by the people around them, because an allergy to cold sounds implausible until you have watched it happen.

This piece is a deep dive into cold urticaria: what it is, its different subtypes, the full spectrum of symptoms from a mild local rash through to anaphylaxis, exactly what to do the moment you suspect a reaction is beginning, the treatments available, the specialists involved in diagnosis and care, a directory of Adelaide-based clinical immunology and allergy specialists, and a detailed look at the everyday triggers that can set a reaction off. Above all, this is written to make one thing clear: if cold makes your skin, your throat, or your whole body react, that is not an inconvenience to push through quietly. It is a medical condition worth having properly assessed.

What Is Cold Urticaria?

Cold urticaria (often abbreviated ColdU) is a form of chronic inducible urticaria — a category of hives with a specific, identifiable physical trigger, rather than hives that appear spontaneously for no clear reason. In cold urticaria, exposure to cold air, cold water, cold objects, or cold food and drink causes the release of histamine and other inflammatory chemicals from mast cells in the skin, producing itchy, red, raised welts (hives) — usually within two to five minutes of the cold exposure, though the reaction is often most intense during rewarming rather than during the cold exposure itself.^1,2

Cold urticaria is considered rare, with one frequently cited estimate placing overall incidence at around 0.05% of the population, though it accounts for roughly 3% of all physical urticarias seen in allergy clinics.^3,4 It most often first appears in young adults (the mean age of onset in acquired cold urticaria is around 22), though it can affect people from infancy through to their seventies, and it is more common in colder climates and in people with a personal or family history of other allergic conditions (atopy).⁴

The exact underlying mechanism is still not fully understood. In most cases, cold exposure is thought to trigger the release of histamine from skin mast cells, though the precise trigger for that release — in some patients, an IgE or IgM antibody that can be detected in the blood, in others no clear antibody at all — varies from person to person.⁵ Most cases are primary (idiopathic), meaning no underlying cause is ever identified. A smaller proportion are secondary, meaning they occur alongside another condition — most often cryoglobulinaemia or cryofibrinogenaemia (abnormal blood proteins that clump in the cold), but sometimes viral infections, some medicines, or, rarely, an underlying blood disorder.^5,6 This is one of the key reasons a proper medical work-up matters: cold urticaria itself is very rarely dangerous to investigate, but occasionally it is the first visible sign of something else that does need attention.

It is worth distinguishing acquired cold urticaria, which is what this piece focuses on, from familial cold autoinflammatory syndrome (FCAS) — an entirely different, genetic condition, present from infancy, that used to be called “hereditary cold urticaria.” FCAS is one of the cryopyrin-associated periodic syndromes and is managed quite differently to the acquired form most people mean when they say “cold urticaria.”⁷

The Different Types of Cold Urticaria

Cold urticaria is not a single, uniform condition. Allergy specialists broadly divide it into typical and atypical forms, based on whether it produces a positive result on standard cold stimulation testing (most often the “ice cube test,” where an ice cube is held against the skin for several minutes to see whether a hive forms).

Typical (Classic) Cold Urticaria

This is the most common presentation, and the one most people picture: localised, itchy hives appear on the exact area of skin that was exposed to cold, usually resolving on their own within one to two hours. It can be further split into:

• Primary (idiopathic) acquired cold urticaria — no identifiable underlying cause; this is the large majority of cases.
• Secondary acquired cold urticaria — associated with an underlying condition such as cryoglobulinaemia, cryofibrinogenaemia, certain infections, or rarely an underlying blood disorder or malignancy.

^6,8

Atypical Cold Urticaria

A meaningful subset of patients have atypical presentations that don’t show up on a standard ice cube test, and instead need more specialised provocation testing to confirm. A 2025 systematic review identified ten recognised atypical subtypes, including:^9,10

• Delayed cold urticaria — wheals appear hours (sometimes 12–48 hours) after the cold exposure, rather than within minutes.
• Localised cold reflex urticaria — a reaction appears near, but not exactly at, the site of cold exposure.
• Systemic (generalised) cold urticaria — widespread symptoms after extensive cold exposure, such as swimming, even though a localised ice cube test may be negative.
• Cold-dependent dermographism — hives form only when previously chilled skin is then mechanically stroked or scratched.
• Cold-induced cholinergic urticaria — reactions occur only when cold exposure is combined with physical exertion.
• Water-dependent, food-dependent, and ultra-freeze cold urticaria — rarer variants requiring specific combinations or extended exposure to provoke a reaction.

Because these atypical forms can test negative on a standard ice cube test, a person can be told “you don’t have cold urticaria” after a quick screening test, when in fact a more thorough, symptom-guided work-up would confirm one of these subtypes. If cold reliably brings on symptoms for you but a basic ice cube test came back negative, it’s reasonable to ask your specialist about further, more targeted testing.⁹

Cold urticaria is also frequently found alongside other physical (inducible) urticarias, most commonly symptomatic dermographism (hives from firm stroking of the skin) and cholinergic urticaria (hives from heat, sweating, or exercise), and up to half of patients with cold urticaria are atopic.⁴

Symptoms: From a Local Rash to a Whole-Body Reaction

Cold urticaria symptoms typically begin within two to five minutes of cold exposure and last one to two hours, though this varies by subtype. Importantly, the reaction is often at its worst not while the skin is cold, but as it warms back up. Symptoms range enormously from person to person, and even from episode to episode in the same person, depending on how much of the body is exposed, for how long, and at what temperature.

Localised (Cutaneous) Symptoms

• Itchy, red, raised welts or hives on the exposed skin — the hallmark sign, usually forming a red, swollen, intensely itchy patch that can range from a coin-sized welt to covering an entire limb.
• A burning or stinging sensation, sometimes preceding the visible rash by a minute or two.
• Angioedema — deeper swelling beneath the skin, especially of the lips, hands, and face, such as swollen lips after eating ice cream or a swollen hand after holding a cold drink can or an ice pack.
• Redness and warmth of the affected area as blood flow increases during the reaction.

^2,11

Systemic (Whole-Body) Symptoms

In up to half of patients, especially with more extensive cold exposure, symptoms can extend beyond the skin. These systemic reactions are more likely when a large surface area of the body is exposed at once — most classically, swimming in cold water.

• Headache
• Palpitations (a racing or pounding heartbeat)
• Flushing
• Abdominal pain, nausea, or vomiting
• Wheeze or difficulty breathing
• Fainting (syncope) or a documented drop in blood pressure — considered the most severe and objective marker of a systemic cold-induced reaction.

^2,12

One figure worth sitting with: in a widely cited case series, cardiovascular symptoms with or without loss of consciousness occurred in 28% of patients with cold urticaria, and syncope or a measured drop in blood pressure occurred in 12%. Respiratory symptoms were reported in 20% and gastrointestinal symptoms in 10%, though other studies have found systemic reactions in anywhere from 4% to 51% of patients, reflecting real variability in how the condition presents.¹²

Anaphylaxis: The Most Serious Reaction, in Detail

In its most severe form, cold urticaria can trigger anaphylaxis — a rapid, whole-body allergic reaction that is a genuine medical emergency. This is most dangerous when a large area of skin is suddenly exposed to cold, such as jumping into a cold pool, lake, or ocean, where the combination of a systemic reaction and being in water has led to fainting and drowning even in otherwise fit, healthy young people.^2,13

The Full Range of Possible Anaphylaxis Symptoms

According to the Australasian Society of Clinical Immunology and Allergy (ASCIA), the signs and symptoms of anaphylaxis are potentially life-threatening and include any one of the following:

• Difficult or noisy breathing
• Swelling of the tongue
• Swelling or tightness in the throat
• Wheeze or a persistent cough
• Difficulty talking, or a hoarse voice
• Persistent dizziness, or collapse
• Becoming pale and floppy (particularly in young children)
• Abdominal pain and vomiting

¹⁴

A mild to moderate allergic reaction can sometimes precede full anaphylaxis, and recognising it early gives you valuable time to prepare. Signs of a mild to moderate reaction include:

• Swelling of the lips, face, or eyes
• Tingling of the mouth
• Hives or welts
• Abdominal pain or vomiting (these can also be early signs of anaphylaxis, so should always be taken seriously)

¹⁴

Certain factors — known as co-factors — can make a cold-triggered reaction more severe. For cold urticaria specifically, these include exercising in cold conditions (such as swimming), consuming alcohol, and the sheer extent and suddenness of cold exposure (a full-body plunge is far riskier than a localised, brief contact).¹⁴

What To Do the Moment You Suspect a Reaction Is Starting

Anaphylaxis requires immediate treatment with adrenaline (epinephrine). Delaying treatment to “wait and see” is one of the most common and most dangerous mistakes people make, and it can turn a survivable reaction into a fatal one. The moment you notice any of the anaphylaxis signs above — not once you’re certain, but at the first hint — follow these steps:

1. Stop the cold exposure immediately. Get out of cold water, away from cold air, or stop eating or drinking whatever is cold, straight away.
2. Give adrenaline (an EpiPen® or other prescribed adrenaline device) without delay if one has been prescribed. Do not wait to see if symptoms improve on their own — adrenaline works best when given early, and there is no meaningful downside to giving it if anaphylaxis turns out to be less severe than feared.
3. Lay the person flat. If breathing is difficult, allow them to sit with legs outstretched instead of lying flat. If they are unconscious or vomiting, place them in the recovery position (on their left side if pregnant). Do not allow them to stand or walk, even if they feel able to — standing can cause a sudden, dangerous drop in blood pressure during anaphylaxis. Hold young children flat, not upright.
4. Call an ambulance (000 in Australia) immediately, even if adrenaline has already been given and the person seems to be improving. Everyone who has had anaphylaxis needs medical observation, because symptoms can return in what’s known as a biphasic reaction.
5. If there is no improvement, or symptoms return, give a second dose of adrenaline after 5 minutes if a second device is available.
6. Stay with the person until the ambulance arrives, keeping them warm (with a blanket, not a heat source) and calm, and remain in the lying or recovery position throughout.

^14,15

If you are with someone who is at risk of cold-induced anaphylaxis and they have a written ASCIA Action Plan for Anaphylaxis, that plan (completed and signed by their treating doctor) is the most reliable, personalised guide — follow it. These plans are typically kept with the person’s adrenaline device and outline exactly which signs mean it’s time to act.¹⁴

A note on swimming: because full-body cold-water immersion is the single highest-risk trigger for cold-induced anaphylaxis, anyone diagnosed with cold urticaria should not swim alone, and should discuss with their specialist whether swimming in cold water is safe for them at all, even with supervision.^2,13

Treatment: What Actually Helps

There is no cure for cold urticaria, and the mainstay of management is a combination of trigger avoidance and medication to control symptoms and reduce the risk of a severe reaction.

Avoidance of Triggers

Avoiding sudden or extensive cold exposure — cold water swimming, very cold drinks and foods, prolonged exposure to cold air or wind — is the first and most reliable line of defence, though it isn’t always fully possible in day-to-day life, especially through an Adelaide Hills winter.

Antihistamines

Second-generation (non-drowsy) H1-antihistamines — such as cetirizine, loratadine, fexofenadine, or rupatadine — are the first-line treatment, taken daily rather than only when symptoms appear.¹⁶ International EAACI guidelines note that for people whose symptoms aren’t controlled on a standard dose, the dose can be increased up to four times the standard amount under medical supervision — this is a well-established, guideline-backed step in urticaria treatment, not an unusual or risky one, though it should always be done with your prescribing doctor’s input rather than self-adjusted.^16,17

Omalizumab (Biologic Therapy)

For people whose symptoms persist despite updosed antihistamines, omalizumab (an injectable anti-IgE antibody, brand name Xolair) is the next step in the treatment algorithm. It is given as an injection, usually every four weeks, and has shown good evidence of benefit specifically in cold urticaria, alongside other forms of chronic inducible urticaria.^18,19 Some patients who don’t respond fully at the standard dose can benefit from an increased dose or a shorter interval between injections, under specialist supervision.¹⁷

Other Options

• Ciclosporin — an immune-modulating medication considered for people who don’t respond adequately to antihistamines and omalizumab together; used less often, and only under specialist care, because of its side-effect profile.
• Cold desensitisation (“cold tolerance induction”) — a historical approach involving gradual, repeated cold exposure to build tolerance. This has generally fallen out of favour and is now considered outdated, given the availability of effective medication and the discomfort and risk involved in the desensitisation process itself.
• Emerging treatments — newer biologic medications, including dupilumab, are currently being studied specifically for chronic inducible cold urticaria in people who remain symptomatic on antihistamines, reflecting ongoing research interest in better options for this condition.

^20,21

Carrying Adrenaline

For anyone who has experienced a systemic reaction or anaphylaxis from cold exposure, their specialist will usually prescribe an adrenaline autoinjector (EpiPen®, Anapen®, or another approved device) to carry at all times, alongside a written ASCIA Action Plan and hands-on training in how and when to use it. In 2026, multiple adrenaline devices are approved for use in Australia, including EpiPen®, Anapen®, Jext®, and neffy® (a nasal spray alternative to an injector).²²

Who to See: Diagnosis, Testing, and Ongoing Care

Cold urticaria is diagnosed and managed by a clinical immunology/allergy specialist, usually following referral from a GP. Diagnosis typically involves a detailed history, a physical examination, and — where appropriate — a cold stimulation test (CST), most commonly the ice cube test, where an ice cube is applied to the forearm for several minutes and the skin is observed for a wheal as it rewarms. More specialised devices, such as the TempTest, can precisely measure the temperature threshold at which a person reacts, which helps guide both diagnosis and day-to-day risk management.^9,23

Where an underlying cause is suspected — particularly in atypical or more severe presentations — additional blood tests may be used to check for cryoglobulins, cryofibrinogen, and other markers, to rule out a secondary cause.

The Professionals Involved

Adelaide and South Australian Specialists

The Australasian Society of Clinical Immunology and Allergy (ASCIA) maintains a directory of accredited clinical immunology/allergy specialists. The following adult and adolescent-treating specialists are currently listed for the Adelaide metropolitan area — availability, referral requirements, and whether an appointment is public or private can change, so it’s worth confirming current details directly, or asking your GP to check ASCIA’s directory, before booking.²⁴

You can search the full, current ASCIA directory yourself at allergy.org.au/patients/locate-a-specialist/sa, and most of these specialists require a GP referral. If you’re in the Adelaide Hills, your GP can refer to any of these clinics or hospitals — none require you to live locally to the practice.

A Deep Dive Into Triggers

What counts as “cold” varies enormously between individuals — some people react only to genuinely icy conditions, while others react to anything below body temperature, including ordinary air conditioning. Understanding your own personal triggers, often established through cold stimulation testing, is central to living well with this condition.

Weather and Environment

• Cold, windy, or damp weather — wind chill in particular can intensify a reaction even when the air temperature alone wouldn’t
• Sudden temperature drops, such as walking from a warm room into a cold night
• Air conditioning, including sitting directly under a vent or a cold car interior on a hot day
• Cold, damp conditions typical of an Adelaide Hills winter morning
  
  

Water Exposure

• Swimming in cold water — the single highest-risk trigger for a severe, systemic reaction, due to the combination of large surface area exposure and being in water if fainting occurs
• Cold showers or baths
• Washing hands in cold water
• Rain, particularly cold rain against exposed skin
  
  

Food and Drink

• Cold or iced drinks, including water straight from the fridge
• Ice cream, iced desserts, and other frozen foods — a classic trigger for lip and mouth swelling
• Cold foods taken directly from the refrigerator or freezer
• In rare food-dependent variants, specific foods combined with cold exposure
  
  

Objects and Contact

• Holding a cold drink can, ice pack, or frozen food item directly against the skin
• Handling frozen or refrigerated goods, including at work (hospitality, retail, warehousing)
• Contact with metal, glass, or other cold surfaces
  
  

Combined and Situational Triggers

• Exercise in cold conditions, which for some people is the trigger only in combination with cold, not cold alone (cold-induced cholinergic urticaria)
• Alcohol, which can lower the threshold at which a reaction occurs and make reactions more severe
• Medical settings involving cold exposure, such as ice packs used for pain relief, cold compresses, or, rarely, cold anaesthetic gases during surgery
• Air travel, where cabin air can be both cold and dry

^2,25,26

Because triggers are so individual, many people find it useful to keep a simple symptom diary in the early stages after diagnosis — noting the temperature, duration of exposure, and reaction — to help their specialist tailor advice and treatment specifically to them, rather than relying on generic guidance alone.

Living Well With Cold Urticaria

• Take prescribed antihistamines daily as directed, rather than only once a reaction has already started — consistent dosing controls the underlying reactivity, not just individual flares
• Carry an adrenaline autoinjector at all times if one has been prescribed, and make sure it hasn’t expired
• Never swim alone, and discuss with your specialist whether cold-water swimming is safe for you at all
• Let workplaces, schools, and sporting clubs know if cold exposure is a genuine risk, and share a copy of your ASCIA Action Plan with people who spend regular time with you
• Warm up gradually after any cold exposure, rather than suddenly, where possible
• Keep a written record of your known triggers and threshold temperature, and bring it to specialist appointments
• Revisit your management plan periodically with your specialist — thresholds and severity can change over time, in either direction

Cold urticaria can feel isolating, particularly because so much of daily life — a cold drink, a swim on a hot day, an air-conditioned office — involves the very thing your body has decided is a threat. That adjustment is real, and it’s worth being patient with yourself while you find what works. With the right antihistamine regimen, a clear action plan, and good specialist support, the overwhelming majority of people with cold urticaria are able to live full, active lives, including swimming, travelling, and enjoying an Adelaide summer, with sensible precautions in place.

Closing Thoughts

Cold urticaria sits in an unusual space: rare enough that many GPs will see only a handful of cases in their career, but common enough, and potentially serious enough, that it deserves proper diagnosis rather than being dismissed as “just sensitive skin.” If cold reliably brings on hives, swelling, or anything beyond the skin — palpitations, dizziness, breathlessness — that’s a signal worth taking to a GP and, from there, to a clinical immunology/allergy specialist.

If this describes you, your child, or someone you love: your reaction is real, it’s measurable, and it’s manageable. You don’t have to simply avoid winter, cold drinks, and swimming forever without a plan — proper diagnosis and treatment can give you a great deal of your life back.

You are not alone, and neither is anyone in your care. There is a whole community of people, families, and clinicians who understand this condition — you don’t have to figure it out by yourself.

Sources

1. Mayo Clinic. “Cold urticaria – Symptoms & causes.” mayoclinic.org.
2. DermNet NZ. “Cold urticaria.” dermnetnz.org.
3. Cleveland Clinic. “Cold Urticaria: What It Is, Symptoms, Causes & Treatment.” my.clevelandclinic.org.
4. Dibbern, D.A. & Dreskin, S.C. (2004). Cold urticaria, summarised via ScienceDirect Topics, Immunology and Allergy Clinics of North America.
5. Maltseva, N. et al. (2021). “Cold urticaria – What we know and what we do not know.” Allergy, Wiley Online Library.
6. NORD (National Organization for Rare Disorders). “Cold Urticaria – Symptoms, Causes, Treatment.” rarediseases.org.
7. NORD. “Cold Urticaria” — Familial cold autoinflammatory syndrome (FCAS) differentiation. rarediseases.org.
8. ScienceDirect Topics. “Cold Urticaria – an overview.” Immunology and Microbiology.
9. Systematic review (2025). “Subtypes of Atypical Cold Urticaria and Recommendations for Their Diagnostic Workup.” Journal of Allergy and Clinical Immunology: In Practice / PubMed.
10. Altmeyers Encyclopedia. “Cold urticaria.” altmeyers.org, Department of Allergology.
11. Mayo Clinic. “Cold urticaria – Symptoms & causes.” mayoclinic.org.
12. “Cold Urticaria: From Wheals to Anaphylaxis.” e-aair.org (Allergy, Asthma & Immunology Research).
13. NORD. “Cold Urticaria – Symptoms, Causes, Treatment,” section on severe systemic reactions and drowning risk. rarediseases.org.
14. ASCIA (Australasian Society of Clinical Immunology and Allergy). “Anaphylaxis – Frequently Asked Questions.” allergy.org.au/patients/about-allergy/anaphylaxis, content updated January 2026.
15. ASCIA. “Action Plans and First Aid Plan for Anaphylaxis” and positioning guidance. allergy.org.au/hp/anaphylaxis.
16. Zuberbier, T. et al. (2022). “The international EAACI/GA²LEN/EuroGuiDerm/APAAACI guideline for the definition, classification, diagnosis, and management of urticaria.” Allergy.
17. “Management of Chronic Spontaneous Urticaria Made Practical: What Every Clinician Should Know.” Journal of Allergy and Clinical Immunology: In Practice.
18. “Omalizumab treatment in patients with chronic inducible urticaria: A systematic review of published evidence.” Journal of Allergy and Clinical Immunology.
19. Dermatology Times. “Chronic urticaria guidelines updated.” dermatologytimes.com.
20. ScienceDirect Topics. “Cold Urticaria – an overview,” section on cold desensitisation.
21. “Dupilumab for the Treatment of Chronic Inducible Cold Urticaria in Patients Who Remain Symptomatic Despite the Use of H1-antihistamine (LIBERTY-CINDU CUrIADS).” ClinicalTrials.gov protocol document.
22. ASCIA. “Anaphylaxis” resource page, adrenaline device availability 2026. allergy.org.au/anaphylaxis.
23. Maltseva, N. et al. (2021). “Cold urticaria – What we know and what we do not know,” section on cold stimulation testing. Allergy.
24. ASCIA. “Locate a Specialist – SA.” allergy.org.au/patients/locate-a-specialist/sa, accessed 2026.
25. Cleveland Clinic. “Cold Urticaria: What It Is, Symptoms, Causes & Treatment,” section on triggers. my.clevelandclinic.org.
26. NORD. “Cold Urticaria – Symptoms, Causes, Treatment,” section on secondary associations and triggers. rarediseases.org.