User's Guide

179
The Bigfoot Unity
™
Diabetes Management System User Guide | Appendix C
Adverse Events
No device related serious adverse events occurred during the studies.
In the Adult study, mild skin irritations, such as erythema, bruising,
bleeding, and scabbing were reported around the insertion site and
adhesive area by a small number of subjects (10 out of 146 or 6.8%).
Pain was mostly reported as none with only one instance of mild pain.
In the Pediatric study, for children ages 12-17 there were 7 instances of
erythema (4 “well-dened redness”, and 3 “slight pink”), 5 instances of
edema (3 slight edema, 2 slight edema with dened edges), 2 instances
of mild bleeding, and one instance of mild induration.
Ascorbic Acid Interference
Taking ascorbic acid (vitamin C) supplements while wearing the Sensor
may falsely raise Sensor glucose readings. Taking more than 500 mg
of ascorbic acid per day may affect the Sensor readings which could
cause you to miss a severe low glucose event. Ascorbic acid can be
found in supplements including multivitamins. Some supplements,
including cold remedies such as Airborne
®
and Emergen-C
®
, may
contain high doses of 1000 mg of ascorbic acid and should not
be taken while using the Sensor. See your health care provider to
understand how long ascorbic acid is active in your body.
Additional notes for Health Care Providers
A clinical study was conducted to evaluate the effect of ascorbic acid
on Sensor performance. Data from 57 adult subjects with diabetes was
collected over a 13-hour period. Each subject had a one-hour baseline
phase where venous blood was collected every 10 minutes. After this
rst hour, a dose of 1000 mg ascorbic acid was given with a meal and
venous samples were collected every 20 minutes for the next four
hours. A maximum average sensor bias of 9.3 mg/dL was observed
around 3 hours after the 1000 mg ascorbic acid dose. Subjects then
received a second dose of 1000 mg ascorbic acid with a meal and the
same process was continued for another 4 hours. A third dose of 1000
mg ascorbic acid was then given and study subjects were followed for
4 more hours. After the second dose of ascorbic acid the maximum
average sensor bias increased, with minimal change in sensor bias after
the third dose, suggesting that saturation had occurred by the second
1000 mg dose of ascorbic acid. The maximum average sensor bias
after the three 1000 mg doses of ascorbic acid was less than
20 mg/dL.