Background: The aging world population had led to an increase in the prevalence of Alzheimer’s
disease (AD). The drugs used to slow down the onset of AD, galantamine, donepezil, rivastigmine
and memantine, are generally well-tolerated. However, drug interactions between these drugs
and other drugs are an important aspect of patient safety that should be borne in mind, particularly
given the high burden of polypharmacy in the elderly. The aim of this review is to provide an updated
review of clinically significant drug-drug interactions concerning drugs approved for AD.
Method: PubMed was searched for relevant keywords. No time limit was imposed but only articles in
English published in peer-reviewed journals were selected. Relevant literature was also identified from
the references of identified articles. Further information was obtained from drug summary of product
Results: The major pharmacokinetic interactions identified concerned fluoxetine, paroxetine and ketoconazole
when used with galantamine or donepezil. On the other hand, the major potential pharmacodynamic
interactions concerned anti-dementia drugs and general anesthesia agents, anti-cholinergic drugs,
conventional antipsychotics and bradycardia-inducing drugs. In clinical practice memantine shows a
lower potential for pharmacodynamic drug-drug interactions (DDIs) compared to other drug classes.
Conclusion: The concomitant use of anti-dementia drugs with other drugs can have variable clinical
effects, making appropriate prescribing of these drugs very challenging. A simple and coherent way of
presenting evidence on complex drug interaction information from heterogenous sources to clinicians
is needed in order for the voluminous data available to have an impact on clinical practice.