Introduction: We update the knowledge, since the last review in 2017, about drug-drug interactions (DDI) of non-
vitamin-K-antagonist oral
anticoagulants (
NOAC) in patients ≥75 years.Areas covered: The literature was searched for: '
dabigatran,' '
rivaroxaban,' '
edoxaban,' or '
apixaban' and drugs, affecting platelet function, CYP3A4-, CYP2C9-, or P-Gp-activity. Pharmacodynamic DDI of
NOAC with drugs affecting platelet function like nonsteroidal anti-inflammatory drugs and
antiplatelet agents occur most frequently. Pharmacokinetic DDI with
NOAC were found for 37 of 117 drugs. Reports about DDI with
NOAC were found for 51% of P-gp-affecting, 38% for CYP2C9-affecting and 27% for CYP3A4-affecting drugs. Reports about DDI of
cardiovascular drugs with
NOAC were the most prevalent, followed by anti-infective and nervous system drugs.
NOAC plasma levels were measured in retrospective and cohort studies and were associated with concomitant medication. Reports about DDI of
NOAC were found in 71 patients ≥75 years.Expert opinion: The knowledge about DDI of
NOAC in elderly patients is very limited. Studies should be carried out to investigate the role of drugs potentially interacting with
NOAC, which until now have not been investigated. When studying DDI of
NOAC, care should be taken to include elderly patients with impaired renal function and patients on
polymedication.