What causes urticaria (hives) to worsen after treatment?

From the Guidelines

If hives worsen after treatment, the most effective approach is to increase the antihistamine dose up to four times the standard amount or add a different class of antihistamine, as recommended by the latest guidelines 1.

Key Considerations

• First-line treatments for hives typically include non-sedating antihistamines like cetirizine (10mg daily), loratadine (10mg daily), or fexofenadine (180mg daily) 1.
• If symptoms worsen, the doctor might add a different class of antihistamine like hydroxyzine (25mg every 6 hours) or prescribe a short course of oral corticosteroids like prednisone (40-60mg daily for 3-5 days) for severe cases 1.
• Worsening hives could indicate chronic urticaria, which may require additional medications such as montelukast (10mg daily), dapsone, or omalizumab injections 1.

Treatment Approach

• The latest guidelines recommend an "as much as needed and as little as possible" approach, by stepping up and stepping down the treatment of CU, based on levels of disease control assessed with the UCT 1.
• In patients who are treated with a standard-dosed second-generation antihistamine and whose CU cannot be completely controlled, a higher dose (up to 4-fold higher) should be used 1.
• Step-down protocols should bring on board individual patient needs and, in general, be implemented with prudence and patience, with patients not stepping down a higher than standard–dosed antihistamine before completing at least 3 consecutive months of complete control 1.

From the FDA Drug Label

XOLAIR may cause serious side effects, including: Severe allergic reaction. A severe allergic reaction called anaphylaxis can happen when you receive XOLAIR. ... hives, or feeling warm ... Your healthcare provider will monitor you closely for symptoms of an allergic reaction while you are receiving XOLAIR and for a period of time after treatment is initiated. If your symptoms do not improve or get worse, call your healthcare provider

The medication XOLAIR (omalizumab) may cause severe allergic reactions, including hives. If hives worsen after treatment, patients should call their healthcare provider. Key points to consider:

• Severe allergic reactions can occur with XOLAIR
• Hives are a possible symptom of an allergic reaction
• Patients should be monitored for symptoms of an allergic reaction
• If symptoms worsen, patients should contact their healthcare provider 2

From the Research

Hives that Worsen After Treatment

• Hives, also known as urticaria, can be a challenging condition to manage, and in some cases, they may worsen after treatment 3, 4.
• Chronic spontaneous urticaria (CSU) is a type of urticaria that lasts for more than 6 weeks and can be difficult to control with standard treatments such as antihistamines 4, 5.
• In some cases, add-on therapies such as omalizumab, immunosuppressive agents, and anti-inflammatory agents may be necessary to control CSU 3, 4.
• Omalizumab has been shown to be effective in treating CSU, with a complete response rate of 82% at 1 year, compared to 66% for hydroxychloroquine 3.
• However, some patients may not respond to these treatments, and alternative therapies may be needed 4, 6.
• It is essential to identify the underlying cause of urticaria, if possible, and to tailor treatment to the individual patient's needs 5, 6.
• In some cases, urticaria may be a symptom of an underlying condition, such as an allergy or autoimmune disorder, and treatment of the underlying condition may be necessary to control the urticaria 6, 7.