Effects of transcutaneous electric acupoint stimulation on drug use and responses to cue-induced craving: a pilot study

Abstract

Background: Transcutaneous electric acupoint stimulation (TEAS) avoids the use of needles, and instead delivers a mild electric current at traditional acupoints. This technique has been used for treating heroin addiction, but has not been systematically tested for other drugs of abuse. This study aims to investigate the effects of TEAS on drug addiction.

Methods: Volunteers who were either cocaine-dependent (n = 9) or cannabis-dependent (n = 11) but were not seeking treatment for their dependence participated in a within-subject, single-blind study. Treatment consisted of twice daily 30-minute sessions of TEAS or sham stimulation for 3.5 days. The active TEAS levels were individually adjusted to produce a distinct twitching response in the fingers, while the sham stimulation involved 2 minutes of stimulation at threshold levels followed by 28 minutes of stimulation below the detection levels. The participants recorded their drug use and drug cravings daily. At 1 hour after the last morning session of TEAS or sham stimulation, a cue-induced craving EEG evaluation was conducted. Event-related P300 potentials (ERPs) were recorded, sorted, and analyzed for specific image types (neutral objects, non-drug-related arousing images, or drug-related images).

Results: TEAS treatment did not significantly reduce the drug use or drug cravings, or significantly alter the ERP peak voltage or latency to peak response. However, the TEAS treatment did significantly modulate several self-reported measures of mood and anxiety.

Conclusion: The results of this pilot study with a limited sample size suggest that the acupoint stimulation techniques and protocol used in this trial alone do not significantly reduce cravings for or use of cocaine or cannabis. The findings that TEAS modulates mood and anxiety suggest that TEAS could be used as an adjunct in a multimodal therapy program to treat cocaine and cannabis dependence if confirmed in a full randomized controlled clinical trial.

Figure 1

Acupoints for electrical stimulation with the HANS device were located by visual inspection, measurement, and palpation of the participant’s hands and forearm/wrist. Four acupoints were stimulated: PC-6 (Neiguan), 2 inches (i.e. 2 cun) proximal of the palm, between the palmaris longus tendon and flexor carpi radialis tendon; TH-5 (Waiguan), 2 inches (i.e. 2 cun) proximal of the skin crease on the back of the wrist, between the ulnar and radius bones; LI-4 (Hegu), at the midpoint of the second metacarpal bone on the radial side; and PC-8 (Laogong), midway between the second and third metacarpal on the palmar side.

Figure 2

Craving scores and daily use mean ± SD by phase of the study for cocaine and marijuana participants. Cravings were ratings on a 10-point scale from 1-‘none’ to 10-‘extremely’. ‘Baseline’ refers to assessments during the one week before any treatment was conducted. A: Cocaine craving; B: Cocaine use; C: Marijuana craving; D: Marijuana use.

Figure 3

Ratings of anxiety during each phase of the study for cocaine and marijuana participants. Anxiety was rated on a 100 mm line with anchors of ‘none’ to ‘extremely’. Left panels are group mean ± SD; right panels are individual participant scores (averaged during Baseline and Sham, but by separate days during TEAS treatment).* significantly different from baseline, P < 0.05. A: Anxiety of cocaine subjects; B: Anxiety of marijuana subjects.

Figure 4

Averaged ERP for four conditions in cocaine abusing subjects (n = 9). Red lines and bars represent averaged responses to neutral pictures after sham TEAS treatment; Blue lines and bars represent responses to neutral pictures after active TEAS treatment; Black lines and bars represent responses to drug pictures after sham TEAS treatment; Green lines and bars represent responses to drug pictures after active TEAS treatment. Bar graph inserts show magnitude of peak response in μV (mean ± SD) averaged across subjects. * indicates significant differences between responses to drug pictures and neutral pictures (P < 0.05). + indicates a statistical trend (P = 0.06). A: Oz; B: Pz; C: Cz; D: Fz.

Figure 5

Averaged ERP for four conditions in marijuana abusing subjects (n = 11). Red lines and bars represent averaged responses to neutral pictures after sham TEAS treatment; Blue lines and bars represent responses to neutral pictures after active TEAS treatment; Black lines and bars represent responses to drug pictures after sham TEAS treatment; Green lines and bars represent responses to drug pictures after active TEAS treatment. Bar graph inserts show magnitude of peak response in μV (mean ± SD) averaged across subjects. A: Oz; B: Pz; C: Cz; D: Fz.