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. Author manuscript; available in PMC: 2022 Dec 1.
Published in final edited form as: Exp Clin Psychopharmacol. 2020 Apr 16;29(6):636–649. doi: 10.1037/pha0000375

Table 1.

Mean Number Signs at Each Timepoint

Baseline 0 hr 16 hrs 48 hrs 72 hrs 168 hrs 312 hrs
Mean SD Mean SD Mean SD Mean SD Mean SD Mean SD Mean SD
Total Sample (N=16)
 Body Temperature (C°) 34.6 1.3 34.6 1.2 34.7 1.3 35.1 1.6 35.2 1.3 35.3 1.5 36.4 1.0
 Body Shakes 0.0 0.0 0.0 0.0 0.1 0.3 0.0 0.0 0.1 0.3 0.1 0.3 0.1 0.5
 Chews 1.9 1.9 2.2 3.9 1.6 1.7 1.1 0.9 0.9 1.3 0.8 1.2 1.1 1.4
 Diarrhea/Defecation 0.0 0.0 0.0 0.0 0.1 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Digs 4.4 5.7 4.6 7.2 1.9 3.4 1.1 2.3 1.4 4.0 2.9 4.6 1.3 2.0
 Escape Attempts 26.0 7.8 21.5 11.3 15.6 8.1 19.8 15.0 16.1 6.6 16.8 10.1 16.3 11.1
 Eye Blinks 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Foot Licks 4.0 2.9 4.4 4.3 19.1 16.1 28.2 32.7 17.3 16.9 16.3 20.0 25.5 35.5
 Genital Licks 1.3 1.7 0.4 0.9 1.1 1.1 1.1 1.5 0.9 1.2 0.5 0.8 0.7 0.6
 Grooms 5.8 2.7 7.5 6.5 18.7 7.8 9.3 7.0 7.1 4.8 9.1 5.3 7.2 5.2
 Head Shakes 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Jumps 1.6 3.1 1.2 2.5 0.4 1.0 0.4 0.6 0.6 1.6 1.1 2.2 0.8 2.5
 Piloerection 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Ptosis 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Rears 4.8 3.5 3.9 4.3 4.3 2.3 5.7 3.4 5.5 3.8 4.4 4.6 4.6 4.8
 Teeth Chatters 0.0 0.0 0.0 0.0 0.1 0.3 0.1 0.3 0.1 0.3 0.0 0.0 0.0 0.0
 Writhes 0.1 0.5 1.6 3.8 1.1 2.7 0.8 2.8 1.6 4.5 0.5 1.3 0.7 2.5
 Total Somatc Signs 49.9 29.8 47.4 44.6 64.1 45.2 67.4 66.5 51.8 45.1 52.4 50.4 58.1 66.1
Male (N=8)
 Body Temperature (C°) 34.8 1.4 34.1 1.0 34.0 0.7 34.7 1.0 34.3 0.8 34.8 0.8 36.0 1.1
 Body Shakes 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.4 0.0 0.0 0.3 0.7
 Chews 2.1 1.5 3.6 5.2 2.5 1.9 1.0 0.9 1.5 1.6 1.4 1.3 1.3 1.2
 Diarrhea/Defecation 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Digs 2.3 2.6 2.3 3.5 0.9 1.5 0.0 0.0 0.1 0.4 1.1 2.1 0.6 0.7
 Escape Attempts 26.6 6.9 24.8 12.7 11.8 5.9 14.1 17.0 14.8 6.5 16.4 11.6 13.6 10.6
 Eye Blinks 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Foot Licks 5.4 3.3 5.5 3.0 14.1 5.0 18.1 18.0 12.5 9.7 9.5 6.4 18.8 31.6
 Genital Licks 1.5 2.0 0.3 0.5 1.1 1.1 1.3 2.1 1.0 1.4 0.6 1.1 0.9 0.6
 Grooms 6.3 3.0 5.8 3.4 20.8 4.6 7.0 4.8 7.5 5.9 9.6 5.3 4.9 3.0
 Head Shakes 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Jumps 0.4 0.7 1.6 3.1 0.0 0.0 0.3 0.7 1.1 2.2 1.5 2.8 1.5 3.5
 Piloerection 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Ptosis 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Rears 5.1 3.8 4.5 5.6 4.4 2.3 6.1 3.8 5.3 4.3 5.9 5.9 6.1 6.1
 Teeth Chatters 0.0 0.0 0.0 0.0 0.3 0.5 0.1 0.4 0.1 0.4 0.0 0.0 0.0 0.0
 Writhes 0.0 0.0 0.4 1.1 0.5 1.4 0.0 0.0 0.0 0.0 0.1 0.4 0.1 0.4
 Total Somatc Signs 49.6 23.8 48.6 38.0 56.3 24.1 48.0 47.7 44.0 32.7 46.1 36.7 48.0 58.4
Female (N=8)
 Body Temperature (C°) 34.3 1.3 35.1 1.2 35.4 1.3 35.5 2.0 36.1 1.0 35.9 1.8 36.9 0.6
 Body Shakes 0.0 0.0 0.0 0.0 0.1 0.4 0.0 0.0 0.0 0.0 0.1 0.4 0.0 0.0
 Chews 1.6 2.4 0.8 1.2 0.8 1.0 1.1 1.0 0.4 0.5 0.3 0.7 1.0 1.7
 Diarrhea/Defecation 0.0 0.0 0.0 0.0 0.1 0.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Digs 6.5 7.2 7.0 9.2 3.0 4.4 2.1 2.9 2.8 5.5 4.6 5.9 1.9 2.7
 Escape Attempts 25.4 9.1 18.3 9.3 19.4 8.5 25.5 10.9 17.5 6.9 17.1 9.3 18.9 11.7
 Eye Blinks 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Foot Licks 2.6 1.8 3.4 5.2 24.1 21.8 38.3 41.6 22.1 21.5 23.1 26.7 32.3 39.9
 Genital Licks 1.1 1.5 0.6 1.2 1.0 1.2 1.0 0.8 0.9 1.0 0.4 0.5 0.5 0.5
 Grooms 5.3 2.4 9.3 8.5 16.6 10.1 11.5 8.4 6.8 3.8 8.5 5.6 9.5 6.1
 Head Shakes 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Jumps 2.9 4.1 0.8 1.8 0.8 1.4 0.5 0.5 0.1 0.4 0.8 1.5 0.0 0.0
 Piloerection 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Ptosis 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Rears 4.5 3.4 3.4 2.8 4.3 2.5 5.3 3.2 5.8 3.5 2.9 2.3 3.0 2.6
 Teeth Chatters 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
 Writhes 0.3 0.7 2.8 5.1 1.8 3.6 1.6 3.9 3.3 6.1 0.9 1.8 1.3 3.5
 Total Somatc Signs 50.1 32.5 46.1 44.3 71.9 55.2 86.9 73.2 59.5 49.1 58.6 54.6 68.3 68.8

Data represent absolute count of withdrawal symptoms following abrupt opioid discontinuation. Values are the number of occurrences observed by raters blinded to the timepoint during a 10-minute observation period (following a 5-minute habituation) for each symptom. Timepoint represents hours since last heroin self-administration. Data represent values from Experiment 2 only.