Sublingual administration of tacrolimus: current trends and available evidence

Widespread anecdotal use of sublingual tacrolimus administration has arisen, although little literature exists to guide practice. Given the paucity of data, we conducted a survey to evaluate the practice of sublingual tacrolimus administration at transplant centers across the United States and evaluated the literature that is currently available. A 10-question online survey assessing the current state of sublingual tacrolimus use was distributed to pharmacists at transplant centers that each performed more than 100 solid organ transplantations in 2013. In addition, a literature review was performed by searching the PubMed database to identify available evidence for the sublingual administration of tacrolimus. The online survey was completed by 59 (65.6%) of the 90 targeted transplant centers, representing 51.3% of all solid organ transplantations performed in 2013. Sublingual administration of tacrolimus was used in all solid organ transplant populations, with ~67% of lung transplant centers using this route for tacrolimus. The most common dose conversion was 2 mg oral to 1 mg sublingual, with 92% of centers opening oral capsules and administering the contents sublingually. Home use of sublingual administration and use in the pediatric population was uncommon. Seven peer-reviewed reports and one abstract were identified in the literature review. Seven of the eight publications reported favorably on sublingual administration, although no consistent dose conversion or method of administration was elucidated. The majority of the transplant centers surveyed found sublingual tacrolimus a viable alternative when oral administration is unavailable. A large robust prospective evaluation of sublingual administration of tacrolimus is imperative to provide the most effective care to solid organ transplant recipients and to ensure optimal safety for both patients and providers who administer the drug.