What to do if a patient develops an allergic reaction to the rivastigmine (Exelon) transdermal patch?

Management of Allergic Reaction to Rivastigmine (Exelon) Transdermal Patch

If a patient develops an allergic reaction to the rivastigmine transdermal patch, discontinue the patch immediately and switch to oral rivastigmine only after negative allergy testing and under close medical supervision. 1

Identifying the Type of Reaction

• Determine whether the reaction is irritant contact dermatitis or allergic contact dermatitis:
  • Irritant contact dermatitis: Pruritic, erythematous, eczematous plaque strictly confined to the borders of the patch 2
  • Allergic contact dermatitis: Vesicles and/or edema, erythema beyond the boundaries of the patch, and lack of improvement 48 hours after removal 2

Immediate Management

• Remove the patch immediately if signs of allergic dermatitis occur 1

• Document the specific anatomical distribution and characteristics of the skin reaction 3

• For mild reactions (erythema, pruritus):

  • Apply topical corticosteroids to affected area 2
  • Consider lipid-based emollients for irritant dermatitis 2

• For severe reactions (widespread rash, systemic symptoms):

  • Discontinue rivastigmine in all forms 1
  • Treat with antihistamines and topical corticosteroids as needed 2
  • Monitor for signs of anaphylaxis and treat accordingly if present 4

Long-term Management Options

Option 1: Switch to Oral Rivastigmine (If Appropriate)

• Switch to oral rivastigmine only after:

  • Negative allergy testing has been performed 1
  • Close medical supervision is available 1
  • Note: Some patients sensitized to rivastigmine by patch exposure may not tolerate rivastigmine in any form 1

• If switching to oral form:

  • Start at lowest dose (1.5 mg twice daily) 1
  • Titrate slowly to minimize gastrointestinal side effects 1
  • Monitor for recurrence of allergic symptoms 1

Option 2: Consider Alternative Medications

• If patient cannot tolerate rivastigmine in any form, consider alternative cholinesterase inhibitors or other dementia medications based on the original indication for rivastigmine 5

Prevention of Future Reactions (If Continuing Patch Use)

• For patients who can continue using the patch with only mild irritant reactions:
  • Rotate application sites daily 6
  • Avoid harsh soaps on application areas 2
  • Avoid applying to recently shaven or damaged skin 2
  • Carefully remove the patch after use 2
  • Consider pre-treatment with topical corticosteroids at application sites 2

Patient Education and Monitoring

• Instruct patients and caregivers to monitor for signs of allergic dermatitis 1
• Emphasize the importance of proper patch application and rotation 6
• Advise patients to contact healthcare provider immediately if skin reactions occur 1
• Schedule follow-up within 2-4 weeks to assess response to management 3

Cautions and Considerations

• Patients with a previous history of application site reaction suggestive of allergic contact dermatitis are contraindicated from using rivastigmine patch again 1
• Isolated cases of generalized skin reactions have been reported in postmarketing experience 1
• Transdermal patches generally have better gastrointestinal tolerability than oral forms, but skin reactions are a unique concern 7
• If treatment is interrupted for more than 3 days, restart at the lowest dose to avoid adverse effects 1