Gago-Sanchez and colleagues in Spain published their one-year, prospective observational study where they looked at the prevalence of actual drug-drug interactions in 309 transplant patients.

They chose transplant patients as there are many potential drug interactions in this population and immunosuppressants also have a narrow therapeutic index. They found that about 22% of the drug-drug interactions were clinically relevant.

Read the full abstract on Pubmed.