TY - JOUR
T1 - Effect of microneedle design on pain in human volunteers
AU - Gill, Harvinder S.
AU - Denson, Donald D.
AU - Burris, Brett A.
AU - Prausnitz, Mark R.
PY - 2008/9
Y1 - 2008/9
N2 - Objectives: To design microneedles that minimize pain, this study tested the hypothesis that microneedles cause significantly less pain than a 26-gauge hypodermic needle, and that decreasing microneedle length and the number of microneedles reduces pain in normal human volunteers. Methods: Single microneedles with lengths ranging from 480 to 1450? μm, widths from 160 to 465 μm, thicknesses from 30 to 100 μm, and tip angles from 20 to 90 degrees; and arrays containing 5 or 50 microneedles were inserted into the volar forearms of 10 healthy, human volunteers in a double-blinded, randomized study. Visual analog scale pain scores were recorded and compared with each other and to the pain from a 26-gauge hypodermic needle. Results: All microneedles investigated were significantly less painful than the hypodermic needle with microneedle pain scores varying from 5% to 40% of the hypodermic needle. Microneedle length had the strongest effect on pain, where a 3-fold increase in length increased the pain score by 7-fold. The number of microneedles also affected the pain score, where a 10-fold increase in the number of microneedles increased pain just over 2-fold. Microneedle tip angle, thickness, and width did not significantly influence pain. Discussion: Microneedles are significantly less painful than a 26-gauge hypodermic needle over the range of dimensions investigated. Decreasing microneedle length and number of microneedles reduces pain.
AB - Objectives: To design microneedles that minimize pain, this study tested the hypothesis that microneedles cause significantly less pain than a 26-gauge hypodermic needle, and that decreasing microneedle length and the number of microneedles reduces pain in normal human volunteers. Methods: Single microneedles with lengths ranging from 480 to 1450? μm, widths from 160 to 465 μm, thicknesses from 30 to 100 μm, and tip angles from 20 to 90 degrees; and arrays containing 5 or 50 microneedles were inserted into the volar forearms of 10 healthy, human volunteers in a double-blinded, randomized study. Visual analog scale pain scores were recorded and compared with each other and to the pain from a 26-gauge hypodermic needle. Results: All microneedles investigated were significantly less painful than the hypodermic needle with microneedle pain scores varying from 5% to 40% of the hypodermic needle. Microneedle length had the strongest effect on pain, where a 3-fold increase in length increased the pain score by 7-fold. The number of microneedles also affected the pain score, where a 10-fold increase in the number of microneedles increased pain just over 2-fold. Microneedle tip angle, thickness, and width did not significantly influence pain. Discussion: Microneedles are significantly less painful than a 26-gauge hypodermic needle over the range of dimensions investigated. Decreasing microneedle length and number of microneedles reduces pain.
KW - Hypodermic needle
KW - Microneedle dimensions
KW - Microneedle length
KW - Transdermal drug delivery
UR - http://www.scopus.com/inward/record.url?scp=55249125056&partnerID=8YFLogxK
U2 - 10.1097/AJP.0b013e31816778f9
DO - 10.1097/AJP.0b013e31816778f9
M3 - Article
C2 - 18716497
AN - SCOPUS:55249125056
SN - 0749-8047
VL - 24
SP - 585
EP - 594
JO - Clinical Journal of Pain
JF - Clinical Journal of Pain
IS - 7
ER -