d-amphetamine increases choice of cigarette smoking over monetary reinforcement.
BACKGROUND
Psychomotor stimulants previously have been found to increase the frequency of cigarette smoking, but it is unclear whether this is due to a non-specific increase in general activity or a specific increase in the reinforcing effects of smoking.


OBJECTIVE
To investigate whether d-amphetamine increases the relative reinforcing effects of cigarette smoking.


METHODS
Ninety minutes after d-amphetamine (7.5, 15 mg/70 kg) or placebo administration, 13 male and female subjects participated in 3-h sessions during which they could make a maximum of 20 choices between cigarette smoking (two puffs per choice), earning money ($0.25 per choice), or neither. In separate sessions, using the same subjects, the effects of d-amphetamine on the frequency of ad libitum smoking was assessed.


RESULTS
During choice sessions, d-amphetamine dose-dependently increased smoking choices from 4.2 +/- 0.6 to 5.7 +/- 0.6. During sessions in which subjects smoked ad libitum, d-amphetamine increased number of cigarettes smoked from 2.8 +/- 0.4 to 3.8 +/- 0.6. Breath carbon monoxide (CO) levels, a measure of smoke exposure, showed corresponding dose-related increases.


CONCLUSIONS
These results are consistent with previous findings that d-amphetamine increases smoking and provide evidence that this effect is due to a drug-produced increase in the relative reinforcing effects of cigarette smoking.
Department of Psychiatry, University of Vermont, 38 Fletcher Place, Burlington, VT 05401, USA.
J W
JW
Tidey
S C
SC
O'Neill
S T
ST
Higgins
D000328:Adult; D001944:Breath Tests; D002248:Carbon Monoxide / Q000032:analysis; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003913:Dextroamphetamine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008297:Male; D012201:Reward; D012881:Skin Temperature / Q000187:drug effects / Q000502:physiology; D012907:Smoking / Q000523:psychology*
D000697:Central Nervous System Stimulants; D002248:Carbon Monoxide; D003913:Dextroamphetamine