OBJECT DRUGS
Cholinesterase Inhibitors:
- Donepezil (Aricept, etc.)
- Galantamine (Razadyne, etc.)
- Rivastigmine (Exelon)
PRECIPITANT DRUGS
Antihistamines:
- Azatadine (Optimine)
- Azelastine (Astelin, etc.)
- Brompheniramine (Dimetapp)
- Chlorpheniramine (Chlor-Trimeton, etc.)
- Cetirizine (Zyrtec)
- Clemastine (Tavist)
- Cyproheptadine (Periactin)
- Dexchlorpheniramine (Polaramine)
- Diphenhydramine (Benadryl, etc.)
- Hydroxyzine (Atarax)
- Promethazine (Phenergan)
- Triprolidine (Actidil)
Comment:
The cholinesterase inhibitors used to treat Alzheimer's dementia are cholinergic, while the antihistamines listed above are anticholinergic. Thus, one would expect that these antihistamines would inhibit the efficacy of cholinesterase inhibitors. The clinical evidence suggests that this may occur. Short-term use of the antihistamines may be less likely to cause problems.
Class 3: Assess Risk & Take Action if Necessary
- Consider Alternative: Consider using an antihistamine with little or no anticholinergic effects, such as cetirizine (Zyrtec), desloratadine (Clarinex), ebastine (Kestine), fexofenadine (Allegra), or loratadine (Claritin).
- Monitor:If the combination is used, monitor for evidence of reduced efficacy of the cholinesterase inhibitor.