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Lon R Hays

Publications and source records attributed to Lon R Hays.

13 recordsLinked to original sources
PubMed2006

Psychiatry in orthodontics. Part 2: Substance abuse among adolescents and its relevance to orthodontic practice.

Substance abuse by adolescents is a serious problem that will touch every orthodontic practice. Recent data show that 40% of tenth graders in the United States will use an illicit drug at some time, and 18% will do so in a 30-day period. These are significant figures that should impact orthodontic diagnosis and treatment planning. The nature of orthodontic treatment is unique in that the orthodontist will see relatively healthy adolescent patients on a monthly basis over a period of years. The orthodontist is in a prime position to recognize potential substance abuse problems and make referrals. This article discusses various types of substance abuse, diagnosis, options for referral, and orthodontic implications.

Adolescent↗
PubMed2006

Psychiatry in orthodontics. Part 1: Typical adolescent psychiatric disorders and their relevance to orthodontic practice.

Adolescence is a time of rapid physical and mental development. It is also a time when many diagnosable psychiatric diseases are first noticed. A prior study showed that a high rate of suicidal behavior is seen in orthodontic practices. The orthodontist is in a unique position among medical practitioners because treatment occurs over several years with frequent appointments. This article is a current review of the etiology, diagnosis, and therapy for several pertinent mental disorders that occur in adolescents, including mood disorders, schizophrenia, attention-deficit hyperactivity disorder, personality disorders, and eating disorders. All have been associated with high rates of suicidal behavior and completed suicides. With a keen eye for the development of psychiatric issues, the orthodontist is in a position to make appropriate referrals, if needed.

Adolescent↗
PubMed2006

Discriminative-stimulus effects of triazolam in women and men.

Benzodiazepines are among the most commonly prescribed therapeutics. Women seem to be more likely than men to be prescribed a benzodiazepine and to use benzodiazepines for nonmedical reasons; they also appear to be at higher risk for benzodiazepine dependence. The aim of the present investigation was to assess the acute behavioral effects of a benzodiazepine in women and men. To accomplish this, 13 volunteers (6 women, 7 men) first learned to discriminate 0.375-mg triazolam, a triazolobenzodiazepine hypnotic. After acquiring the discrimination, (i.e., >80% correct responding on 4 consecutive sessions) a range of doses of triazolam (0, 0.0625, 0.125, 0.25, and 0.375 mg) were tested in each participant. Triazolam dose dependently increased drug-appropriate responding and subject ratings of sedation and impaired performance (i.e., significant effect of dose). The women and men did not differ significantly on any measure. The results of the present experiment suggest that women and men are not differentially sensitive to the behavioral effects of triazolam.

Anti-Anxiety Agents↗
PubMed2006

Adverse impact of a history of violence for women with breast, cervical, endometrial, or ovarian cancer.

OBJECTIVE: The experience of physical and sexual violence (victimization) is common among U.S. women and is associated with adverse health consequences. The study objectives were to estimate the prevalence of victimization in women with cancer and to examine associations with demographics, cancer screening, and cancer stage. METHODS: From 2004 to 2005, 101 women with breast, cervical, endometrial, or ovarian cancer were interviewed to collect demographics, cancer screening history, health care access/use, and violence history. Chi-square and Fisher exact tests were used test risk-factor associations. A multinomial logistic regression model was used for multivariable analysis. RESULTS: The prevalence of a history of violence was 48.5% (49/101 women), and within that group, 46.9% (23/49) had a positive childhood violence screen, 75.5% (37/49) had a positive adult screen, and 55% (27/49) reported sexual violence at any age. Women with a positive violence screen differed significantly from women with a negative screen in that they were younger (P = .031), more often divorced (P = .012), more likely to smoke (P = .010), more often lacked commercial insurance (P = .036), and had more advanced stage of disease (P = .013), but they did not differ with regard to race, cancer type, education level, alcohol or drug use, or cancer screening compliance. Multivariable analysis revealed that only stage remained significant; women with a history of violence had a 2.6-fold increased chance of diagnosis in later stages (odds ratio 2.61, 95% confidence interval 1.03-6.59). CONCLUSION: A history of violence in breast, ovarian, endometrial, and ovarian cancer patients was extremely common and correlated with advanced stage at diagnosis. LEVEL OF EVIDENCE: II-2.

Breast Neoplasms↗
PubMed2005

Aripiprazole attenuates the discriminative-stimulus and subject-rated effects of D-amphetamine in humans.

The results of animal research suggest that the use of partial agonists at dopamine (DA) D2 receptors may be an effective strategy for the treatment of stimulant dependence. Aripiprazole is an atypical antipsychotic that has partial agonist activity at D2 receptors. In this experiment, seven human participants with a history of nontherapeutic stimulant use learned to discriminate 15 mg oral D-amphetamine. After acquiring the discrimination (ie > or =80% correct responding on four consecutive sessions), the effects of a range of doses of D-amphetamine (0, 2.5, 5, 10, and 15 mg), alone and in combination with aripiprazole (0 and 20 mg), were assessed. D-Amphetamine alone functioned as a discriminative stimulus, produced prototypical subject-rated drug effects (eg increased ratings of Active, Alert, Energetic) and elevated cardiovascular indices. These effects were generally a function of dose. Aripiprazole alone did not occasion D-amphetamine-appropriate responding or produce subject-rated effects, but modestly impaired performance. Administration of aripiprazole significantly attenuated the discriminative-stimulus and cardiovascular effects of D-amphetamine, as well as some of the subject-rated drug effects. These data are consistent with previous preclinical findings and suggest that DA partial agonists deserve further evaluation as potential pharmacotherapies in the management of stimulant dependence. Future studies should investigate the ability of aripiprazole or related compounds to attenuate the behavioral effects of stimulants associated with a greater degree of dependence, such as methamphetamine or cocaine, in dependent individuals.

Adult↗
PubMed2004

Acute administration of the GABA reuptake inhibitor tiagabine does not alter the effects of oral cocaine in humans.

Drugs affecting central gamma-aminobutyric acid (GABA) systems may have promise as treatments for cocaine addiction. In the present study, tiagabine (Gabatril), a GABA reuptake inhibitor, was investigated for its ability to modify the discriminative-stimulus, reinforcing, subject-rated, performance and cardiovascular effects of oral cocaine in non-treatment seeking cocaine users. Initially, acute doses of 4 mg tiagabine were tested alone and in combination with oral cocaine in four participants to establish the safety of cocaine-tiagabine combinations. A higher dose of tiagabine (8 mg) was then tested in a larger group (n = 6). Participants learned to discriminate 150 mg of oral cocaine. The effects of cocaine (0-150 mg, p.o.) administered alone and in combination with tiagabine were then determined. Subject-rated, performance and cardiovascular measures were obtained at regular intervals. The reinforcing effects of cocaine, tiagabine and cocaine-tiagabine combinations were assessed using the Multiple-Choice Procedure. Cocaine alone produced prototypical behavioral and physiological effects (i.e., functioned as a discriminative and reinforcing stimulus, produced stimulant-like subject-rated effects, improved performance and increased heart rate). In general, acute administration of tiagabine did not alter the effects of oral cocaine. These findings suggest that tiagabine would not be effective at preventing continued cocaine use by blocking its acute, abuse-related effects.

Administration, Oral↗
PubMed2004

Alprazolam attenuates the behavioral effects of d-amphetamine in humans.

The results of preclinical behavioral pharmacology studies suggest that gamma-aminobutyric acidA (GABAA) receptor modulators attenuate the behavioral effects of commonly abused stimulants such as amphetamines and cocaine under a variety of behavioral arrangements including drug discrimination and self-administration. In the present experiment, 6 healthy humans learned to discriminate 15-mg oral D-amphetamine. After acquiring the discrimination (ie, . > or = 80% correct responding on 4 consecutive days), the effects of a range of doses of D-amphetamine (0, 2.5, 5, 10, and 15 mg), alone and following pretreatment with alprazolam (0 and 0.5 mg), a GABAA receptor modulator, were assessed. D-Amphetamine alone functioned as a discriminative stimulus and produced stimulant-like self-reported drug effects (eg, increased scores on a Stimulant-Sensitive Adjective-Rating Scale). These effects were generally a function of dose. Alprazolam alone did not occasion D-amphetamine-like discriminative stimulus effects, nor did it increase ratings of sedation or impair performance. Alprazolam pretreatment significantly attenuated the discriminative stimulus effects of D-amphetamine, and some of the self-reported drug effects. Future human laboratory experiments should compare the behavioral effects of D-amphetamine alone and following pretreatment with alprazolam using other behavioral arrangements such as drug self-administration. Future laboratory experiments with humans should also determine if benzodiazepines with lower abuse potential (eg, oxazepam) might also attenuate the behavioral effects of D-amphetamine.

Adolescent↗
PubMed2004

A profile of OxyContin addiction.

OxyContin is a controlled-released form of oxycodone indicated for the management of moderate to severe pain. OxyContin diversion and abuse has become a major problem in certain areas of the United States, particularly rural areas and Appalachia. This study undertakes an 18-month retrospective chart review at a private freestanding psychiatric facility to develop a profile of OxyContin addicts seeking treatment. There were 579 admissions to the Addictive Disease Unit of this facility from October 2000 to March 2002, with 298 of these admissions being for the treatment of opioid abuse or dependence. One hundred and eighty seven of these individuals were dependent on OxyContin, using an average dose of 184 milligrams of OxyContin per day. The OxyContin dependent individuals tended to show a progression from p.o. use to either snorting or i.v. use. The author concludes that a sociocultural understanding is needed to better treat these addicts as is improved communication between the pain treatment community and the addiction treatment community.

Adult↗
PubMed2003

Baclofen does not alter the reinforcing, subject-rated or cardiovascular effects of intranasal cocaine in humans.

RATIONALE: There is evidence from research in animals and humans that the gamma-aminobutyric acid B receptor subtype (GABA(B)) agonist baclofen may have promise as a pharmacotherapy for cocaine addiction. OBJECTIVES: In the present study, the ability of baclofen to modify the reinforcing, subject-rated and cardiovascular effects of intranasal cocaine in humans was determined. METHODS: Non-treatment-seeking volunteers ( n=7) with recent histories of cocaine use were recruited to participate in this placebo-controlled, double-blind study. Baclofen (0, 10, 20 and 30 mg) was administered orally, followed approximately 1.5 h later by intranasal cocaine (4 mg [placebo] and 45 mg). Subject-rated and cardiovascular measures were taken prior to baclofen administration and then at regular intervals after cocaine was administered. The reinforcing effects of cocaine and cocaine-baclofen combinations were assessed using the Multiple-Choice Procedure. RESULTS: Intranasal cocaine significantly increased the crossover point on the Multiple-Choice Procedure relative to placebo, suggesting that this cocaine dose functioned as a reinforcer. This dose of intranasal cocaine also produced increases in subject-rated effects typical of psychostimulants and elevated cardiovascular measures. The time course for the effects of cocaine was consistent with its pharmacokinetic profile following intranasal administration; increases in subject-rated and cardiovascular effects were observed almost immediately following administration and peaked at approximately 30 min. Pretreatment with baclofen had no significant effect alone, nor in combination with cocaine, on any outcome. CONCLUSIONS: These data demonstrated that acute administration of three clinically relevant baclofen doses did not influence the acute behavioral effects of intranasal cocaine in humans.

Administration, Intranasal↗
PubMed2003

Risperidone attenuates the discriminative-stimulus effects of d-amphetamine in humans.

Studies conducted with nonhuman laboratory animals have consistently shown that atypical antipsychotics that are mixed dopamine and serotonin antagonists attenuate the discriminative-stimulus effects of amphetamine. In the present experiment, eight healthy humans learned to discriminate 15 mg of oral d-amphetamine. After acquiring the discrimination (i.e., > or = 80% correct responding on four consecutive days), the effects of a range of doses of d-amphetamine (0, 2.5, 5, 10, and 15 mg), alone and after pretreatment with risperidone (0 and 1 mg), a D2 dopamine and 5-hydroxytryptamine (5-HT)2 serotonin antagonist, were assessed. d-Amphetamine alone functioned as a discriminative stimulus and produced stimulant-like self-reported drug effects (e.g., increased ratings of "like drug"). These effects were generally a function of dose. Risperidone alone did not occasion d-amphetamine-appropriate responding, but impaired performance. Risperidone pretreatment significantly attenuated the discriminative-stimulus effects of d-amphetamine, and some of the self-reported drug effects. The results of the present experiment suggest that combining drug-discrimination and self-reported drug-effect questionnaires may be an effective strategy for assessing the behavioral effects of agonist-antagonist interactions. Future studies should compare the behavioral effects of d-amphetamine after pretreatment with a selective D2 dopamine (e.g., haloperidol) or 5-HT2 serotonin (e.g., ritanserin) antagonist to determine the relative contribution of dopamine and serotonin systems in mediating the behavioral effects of stimulants in humans. The results of these studies might guide the development of a pharmacotherapy for the treatment of amphetamine abuse/dependence.

Adolescent↗
PubMed2003

Discriminative-stimulus effects of triazolam in light and moderate drinkers.

BACKGROUND: The results of previous laboratory experiments with humans suggest that light and moderate drinkers respond differentially to the effects of benzodiazepines. The aim of this study was to further assess the behavioral effects of a benzodiazepine in light and moderate drinkers. METHODS: To accomplish this aim, 12 volunteers (6 light drinkers and 6 moderate drinkers) learned to discriminate 0.375 mg of triazolam, a triazolobenzodiazepine hypnotic. After they learned this discrimination, a test-of-novel-doses phase was conducted in which a range of doses of triazolam (0, 0.06, 0.125, 0.25, and 0.375 mg) was tested in both groups of volunteers. The subject-rated and performance-impairing effects of triazolam were assessed concurrently. RESULTS: There was not a significant difference between the groups in terms of the number of trials needed to learn the discrimination, nor did the proportion of light and moderate drinkers who learned to accurately discriminate 0.375 mg of triazolam differ significantly. The discriminative-stimulus, subject-rated, and performance-impairing effects of triazolam were an orderly function of dose but did not differ across the light and moderate drinkers. CONCLUSIONS: Future studies should examine the discriminative-stimulus effects of a lower dose of triazolam (e.g., 0.25 mg) in light and moderate drinks or use a fading procedure to determine differences in terms of the lowest discriminable dose.

Adult↗
PubMed2002

Discriminative-stimulus effects of modafinil in cocaine-trained humans.

Modafinil is a novel stimulant that is effective in the treatment of narcolepsy and excessive daytime sleepiness. In vitro and in vivo neuropharmacological data suggest that the mechanism of action of modafinil is distinct from that of prototypical abused stimulants like cocaine and d-amphetamine. In the present experiment, six human volunteers with recent histories of cocaine use learned to discriminate 150 mg oral cocaine HCL. After acquiring the discrimination (i.e. > or = 80% correct responding on 4 consecutive days), a range of doses of oral cocaine (50, 100, and 150 mg), modafinil (200, 400, and 600 mg), and placebo were tested to determine if they shared discriminative-stimulus and self-reported effects with 150 mg cocaine. Methylphenidate (60 mg) and triazolam (0.5 mg) were included as positive and negative controls, respectively. Cocaine and methylphenidate, but neither modafinil nor triazolam, produced cocaine-like discriminative-stimulus, subject-rated, and cardiovascular effects. The results of the present experiment suggest that cocaine discrimination in humans is pharmacologically specific within and across drug classes.

Adult↗