CHRONIC SPONTANEOUS URTICARIA (CSU)
(CHRONIC SPONTANEOUS HIVES)
Definition:
- Chronic: Hives for ≥ 6 weeks
- Spontaneous: not from an allergy
- Urticaria: Hives (raised, red itchy bumps/welts)
- Often associated with Angioedema: Swelling (like deeper hive, beneath skin)
- CSU is a benign (not dangerous, just annoying) medical condition
Cause:
- CSU is THE most common cause of chronic hives in adults (>95% of cases)
- CSU is NOT caused by allergies
- “Idiopathic” a bad name (do know cause):
- ~50% patients with CSU have an abnormal antibody
- Antibodies are proteins that are normally made to fight infection
- Instead of fighting infection, this antibody causes hives
- Triggers: stress (emotional or physical), colds, fever, infection, heat, exercise, pressure, NSAIDS (group of anti-inflammatory medication such as Aspirin, Motrin, Ibuprofen, Aleve, Naproxen), Opiates (such as codeine, morphine), alcohol
- The above are POSSIBLE triggers therefore if they are not causing you problems, don’t worry about it.
- Triggers can make the
hives worse but are NOT the cause of the hives
How long does it last?:
- Variable: Lasts months to years. Average 3-5 years
- When the hives disappear, they can come back months to years later
Treatment:
- Antihistamines regularly (take every day to prevent hives)
- Antihistamines are safe to take long term
- Reactine (Cetirizine) 10mg-40mg once/day
- Aerius (desloratidine) 5mg-20mg once/day
- Allegra (Fexofenodine) 120mg-240mg once/day
- Claritin (Loratidine) 10mg-40mg once/day
- Blexten (Bilastine) - by prescription
- Rupall (Rupatadine) - by prescription
- Xolair (omalizumab, anti-IgE) - injection prescribed by specialist
- All the above antihistamines are 24hr (once/day)
- If necessary, there are other medications that also work
*** Created by Dr. Ellie Tsai MD, FRCPC Kingston Allergy and Asthma 613-546-6673***