Digital pill biosensors for monitoring opioid medication use

In a research paper published in the Anesthesia & Analgesia, Brigham and women’s hospital investigators report on the results from a pilot study of 15 individuals who received a prescription to take oxycodone digital pills as needed following treatment for acute fractures.

Recently first digital pill was approved by the FDA for use with the antipsychotic drug Abilify, used to treat schizophrenia, bipolar disorder and depression. Opioids such as oxycodone are frequently prescribed on an as-needed basis for managing acute conditions, but uncertainty exists around how patients take the prescribed drug. Digital pills may offer a unique window into patterns of medication usage.

To conduct their pilot study, the investigators approached 26 individuals in the Emergency Department who had been diagnosed with an acute fracture. (Fifteen completed the study.) The team instructed participants to use oxycodone (one to two 5-mg oxycodone digital pills every six to eight hours) as needed for pain. Unused pills were returned after seven days.

The team used the eTectRx ID-Cap system. Each pill in the system consists of a unique radiofrequency emitter and a standard gelatin capsule containing an oxycodone tablet. When the capsule dissolves, the medication is released, and chloride ions energize the emitter. The patient wears a sticky patch on their abdomen, attached to a cable reader (the size of an iPod) that stores data about pill ingestion. (Since the study was conducted, advances in the technology have miniaturized the reader and added steps to validate the user of the system and provide directed feedback through a smartphone app.)

The digital pill system recorded a total of 112 ingestion events, compared to 134 ingestions based on pill count (84 percent accuracy). However, all missed ingestion events were traced back to two study participants who ingested digital pills without wearing the reader or did not interact with the reader due to severe pain. Most oxycodone doses were ingested within the first three days after discharge. On average, patients ingested only six pills, despite being given 21.

Citation: Chai, Peter R., Stephanie Carreiro, Brendan J. Innes, Brittany Chapman, Kristin L. Schreiber, Robert R. Edwards, Adam W. Carrico, and Edward W. Boyer. “Oxycodone Ingestion Patterns in Acute Fracture Pain With Digital Pills.” Anesthesia & Analgesia 125, no. 6 (2017): 2105-112.
doi:10.1213/ane.0000000000002574
Funding: National Institutes of Health
Adapted from press release by Brigham And Women’s Hospital.