To determine the effect of housing conditions on morphine self-administration, rats isolated in standard laboratory cages and rats living socially in a large open box (8.8 m2) were given morphine in solution (0.5 mg/ml) as their only source of fluid for 57 days. They were then exposed to a series of 3-day cycles previously shown by Nichols et al. (1956) to increase self-administration of morphine in caged rats. On morphine/water choice days late in the period of forced consumption, between the Nichols cycles, and during a subsequent period of abstinence, the isolated rats drank significantly more morphine solution than the social rats, and the females drank significantly more morphine solution than the males. During the four choice days in the Nichols Cycle Period the isolated rats increased their consumption, but the socially housed animals decreased theirs.

No abstract

To determine whether opiate consumption is affected by laboratory housing, individually caged and colony rats were given a choice between water and progressively more palatable morphine-sucrose solutions. The isolated rats drank significantly more of the opiate solution, and females drank significantly more than males. In the experimental phase during which morphine-sucrose solution consumption was greatest, the isolated females drank five times as much, and the isolated males sixteen times as much morphine (mg/kg) as the colony females and males respectively.

There is conflicting evidence regarding the relation between heaviness of smoking and the likelihood of quitting smoking. We investigated this issue using the data set of the 1986 Adult Use of Tobacco Survey, a telephone survey of the smoking behavior of noninstitutionalized, civilian, US adults aged greater than 16 years. Analyses were based on a subsample of 4,383 individuals who had made a serious attempt to stop smoking 1-10 years before the survey. Among younger smokers, the lighter smokers (less than 25 cigarettes/day) were the most likely to stop, whereas among older smokers, the heavier smokers (greater than or equal to 25 cigarettes/day) were the most likely to stop. These results indicate that age is an important factor in the relation between heaviness of smoking and success in quitting smoking.

BACKGROUND:Many physicians are overly cautious about prescribing opioids for chronic pain because of fears of iatrogenic addiction. However, in patients with chronic pain, addiction to opioid analgesics is exceedingly rare when there is no prior history of alcohol or drug abuse.OBJECTIVE:To validate an instrument that separates possible opioid abusers from those who are at low risk.DESIGN/METHODS:The Screening Instrument for Substance Abuse Potential (SISAP) was designed to identify individuals with a possible substance abuse history quickly and accurately. It is based on the National Alcohol and Drug Use Survey (n=9915). Using the first half of the sample (n=4967), two previously validated alcohol use items were combined with three illicit drug use items. These five questions identified those with a history of alcohol and/or illicit drug use.RESULTS:Using the second half of the sample (n=4948), the validation procedure showed that the five combined items correctly classified 91% of substance abusers and had a low rate of false negatives.DISCUSSION:The SISAP is brief and resistant to misrepresentation or falsification. The SISAP is expected to improve pain management by facilitating focus on the appropriate use of opioid analgesics and therapeutic outcomes in the majority of patients who are not at risk of opioid abuse, while carefully monitoring those who may be at greater risk.