What is the management of urticaria in a patient taking lorazepam (Ativan)?

Management of Urticaria in Patients Taking Lorazepam

For patients taking lorazepam who develop urticaria, the first step is to identify and discontinue any causative drug, while managing symptoms with second-generation non-sedating H1 antihistamines as first-line treatment. 1

Determining if Lorazepam is the Cause

• Lorazepam is not commonly listed among frequent causes of drug-induced urticaria, unlike NSAIDs, penicillins, and sulfonamides which are more common triggers 2
• Perform a careful medication review to identify the true culprit, as other medications or factors may be responsible rather than lorazepam 1
• Common drug triggers for urticaria include:
  • NSAIDs and aspirin (frequent triggers working through leukotriene formation) 1
  • Codeine and opioids (cause non-immunological urticaria through direct mast cell degranulation) 1
  • ACE inhibitors (particularly associated with angioedema) 1

First-Line Treatment Approach

• Start with second-generation non-sedating H1 antihistamines such as cetirizine, desloratadine, fexofenadine, levocetirizine, or loratadine 3, 4
• Offer at least two different non-sedating antihistamines as individual responses vary 3
• For inadequate symptom control, increase the dose up to 4 times the standard dose when benefits outweigh risks 3, 4
• Apply cooling antipruritic lotions (calamine or 1% menthol in aqueous cream) for symptomatic relief 1

Management Algorithm for Urticaria in Patients on Lorazepam

1. Assessment Phase:

   • Determine if lorazepam is the likely cause or if another medication/trigger is responsible 1
   • Consider timing of urticaria onset in relation to lorazepam initiation 2
   • Rule out other common triggers (NSAIDs, stress, heat, alcohol) 3

2. If Lorazepam is Suspected:

   • Consider discontinuation if clinically appropriate and replace with alternative anxiolytic/sedative 1
   • In rare cases of benzodiazepine-induced urticaria, switching to a structurally different anxiolytic may be necessary 5

3. If Lorazepam is Not the Cause:

   • Continue lorazepam if needed for the patient's underlying condition 1
   • Identify and address other potential triggers 1, 6

4. Symptom Management (Regardless of Cause):

   • Start with standard dose of second-generation H1 antihistamine 3, 4
   • If inadequate control, increase antihistamine dose up to 4x standard dose 3, 4
   • For nighttime symptoms, consider adding a sedating antihistamine at night 1
   • For severe acute urticaria, a short course of oral corticosteroids may be used 1

Second and Third-Line Treatments for Refractory Cases

• For chronic urticaria unresponsive to high-dose antihistamines:
  • Add omalizumab (anti-IgE monoclonal antibody) at 300 mg every 4 weeks 3, 4
  • Allow up to 6 months for response to omalizumab before considering alternatives 3
• For patients not responding to antihistamines and omalizumab:
  • Consider cyclosporine at 4 mg/kg daily for up to 2 months 3, 4
  • Monitor blood pressure and renal function regularly (every 6 weeks) 3

Special Considerations and Pitfalls

• Antihistamines themselves can rarely cause urticaria, so monitor for paradoxical reactions to treatment 7
• Avoid NSAIDs in aspirin-sensitive patients as they can worsen urticaria 1
• Avoid ACE inhibitors in patients with angioedema 1
• Be aware that benzodiazepines like clotiazepam have been used successfully to treat certain forms of stress-induced urticaria 5
• Inadequate antihistamine dosing is a common pitfall; many patients require higher than standard doses 1
• Prolonged corticosteroid use should be restricted to short courses for severe acute episodes 1

Prognosis

• For chronic urticaria, about 50% of patients with wheals alone will be clear by 6 months 4
• Patients with both wheals and angioedema have a poorer outlook, with over 50% still having active disease after 5 years 4