The prescription of dexamphetamine to patients with schizophrenia and amphetamine dependence

Patients with a severe mental illness such as schizophrenia have significant rates of concurrent amphetamine use. Such dual diagnosis patients have been shown to have poorer treatment outcomes. Often, they do not comply with treatment plans and have frequent episodes of hospitalization. There is growing evidence for the role of prescribed dexamphetamine in the treatment of amphetamine dependence. The prescription of dexamphetamine to patients with schizophrenia and amphetamine dependence has not been previously reported. Eight schizophrenic patients are described to whom dexamphetamine has been prescribed, with information being extracted retrospectively from case notes. In four out of eight cases, the prescription of dexamphetamine led to apparently good progress both in terms of substance misuse and psychiatric health. In two cases, progress was more equivocal, but appeared to produce some benefit. Two cases could be judged as treatment failures, but the condition and situation of the patients were not worse at the end of treatment than at the beginning. Compliance with neuroleptics increased in most cases. No patients exhibited exacerbation of psychosis as a result of treatment. The rate of outcome success is satisfactory when consideration is given to the difficult nature of this patient group, and their previous failure to respond to intensive treatment. It is argued that benefits may be gained from increased compliance with psychiatric treatment in patients prescribed amphetamine, and that this may outweigh possible risks. However, any conclusions are tentative in view of the nature of this study. A small open-label prospective study is recommended.

Psychostimulant use in the rehabilitation of individuals with traumatic brain injury

BACKGROUND

Psychostimulants are used commonly in the rehabilitation of individuals with traumatic brain injury (TBI), despite the dearth of well-controlled studies of their effects. The available literature suggests that these drugs predominantly affect the speed of cognitive processing and certain observational ratings of mood and behavior. Effects on sustained attention, distractibility, and memory are less clear.

OBJECTIVE

This article reviews the controlled research literature on the use of these drugs in TBI and presents preliminary data from the authors' laboratory that extends these findings. Some of the common research pitfalls that have limited progress in research on these drugs are discussed.

Steady-state pharmacokinetics and tolerability of modafinil administered alone or in combination with dextroamphetamine in healthy volunteers

The potential for a drug-drug interaction between modafinil and dextroamphetamine, each at steady state, was investigated in an open-label, randomized, single-period studyin 32 healthy male and female volunteers. All subjects received modafinil orally once daily for 28 days (200 mg on Days 1-7; 400 mg on Days 8-28). On Days 22 to 28, half of the subjects also received dextroamphetamine (20 mg) orally 7 hours after modafinil. Samples for pharmacokinetic (PK) profiling were obtained on Days 21 and 28. The mean changes in PK parameters for modafinil and its two circulating metabolites between the two groups were not statistically significantly different, except Cmax for modafinil acid. Adverse events obtained in the two groups were similar and mild or moderate in nature. The results indicate that administration of low-dose dextroamphetamine in this dosing regimen does not alter the steady-state pharmacokinetics of modafinil. The combination has a similar tolerability profile as modafinil alone.

Two unusual cases of toxic epidermal necrolysis

Two cases of toxic epidermal necrolysis (TEN) are presented. A 27-year-old woman presented with peripherally located targetoid plaques, papules, blisters and lip erosions which began 9 days after 'recreational' use of 'speed' (dexamphetamine and ephedrine) consistent with erythema multiforme major. Three days later she developed widespread lesions with large areas of blistering affecting 40% of body surface area. The diagnosis was revised to TEN. Intravenous cyclosporin led to rapid prevention of new blister formation. A 71-year-old woman, 3 months after commencing amiodarone, developed extensive erythema, blistering and erosions affecting 50% of body surface area, with a maculopapular rash affecting the limbs and extremities consistent with a diagnosis of TEN. She developed septicaemia following bilateral pneumonia with pleural effusions and died 7 days after admission.

Inhibition of dopamine efflux in the rat nucleus accumbens during abstinence after free access to d-amphetamine

Abstinence following 'binge' use of psychostimulants is hypothesized to be related to a depletion of synaptic dopamine (DA) in the nucleus accumbens. The present study, therefore, tested the pharmacological responsiveness of the mesolimbic DA system to d-amphetamine injections, measured by in vivo chronoamperometry with stearate-modified graphite paste electrodes, during voluntary abstinence when rats were given prolonged free availability to d-amphetamine. Rats self-administered i.v. d-amphetamine (FR-1 time out 30 s; 0.25 mg/kg per inf) in three sessions, each separated by approximately 24 h, (1) to a criterion of 12 infusions; (2) for 24 h and (3) for 48 h. During the third session, when self-administration had ceased for at least 1.5 h (abstinence), and DA levels were near, or below, pre-drug baseline values, rats received passive i.v. injections of d-amphetamine or vehicle in a pattern that mimicked self-administration patterns during the first hour of the 48 h session. In contrast to the significant increases in DA efflux observed during the first hour of self-administration, d-amphetamine injections during abstinence did not increase DA oxidation currents. Furthermore, the length of the abstinence period was correlated with the time required for DA to return to pre-abstinence values. Together, these results suggest that the mesolimbic DA system is pharmacologically unresponsive to the actions of d-amphetamine during abstinence, and that resumption of drug use is associated with 'recovery of function' in the mesolimbic DA system.

Repeated electroconvulsive shock attenuates the depressive-like effects of d-amphetamine withdrawal on brain reward function in rats

RATIONALE

The withdrawal of humans from high doses of psychostimulant drugs can result in a transient syndrome which appears isomorphic to endogenous depression. One of the more prominent symptoms is a loss of hedonic capacity; in animals, the anhedonia associated with amphetamine withdrawal has been measured objectively by decrements in responding for intracranial self-stimulation (ICSS).

OBJECTIVE

To date, the effects of amphetamine withdrawal on ICSS responding have been reversed by different antidepressant drugs. In the present study, we sought to reverse withdrawal-induced anhedonia by administration of repeated electroconvulsive shocks (ECS).

METHODS

Rats with electrodes in the lateral hypothalamus were trained on an ascending-series current intensity ICSS paradigm until stable levels of responding were attained. Half of the animals were then administered a 4-day escalating dose schedule of d-amphetamine, and tests for ICSS responding started 12 h after the final injection. During withdrawal, all animals received daily treatment with either ECS or sham-ECS.

RESULTS

Amphetamine withdrawal was associated with reduced ICSS responding; animals treated with ECS exhibited a facilitated recovery compared to sham-ECS treated animals, and returned to control levels of ICSS responding 24 h earlier.

CONCLUSIONS

ECS was able to mitigate the anhedonic effects of d-amphetamine withdrawal, and provides additional support for the use of psychostimulant withdrawal as a model of depression.

The effect of stimulants on nocturnal motor activity and sleep quality in adults with ADHD: an open-label case-control study

OBJECTIVE

Sleep disturbances are common in adults with attention-deficit/hyperactivity disorder (ADHD). In a case-control study, adult ADHD was associated with increased nocturnal motor activity and reduced self-perceived quality of sleep.

METHOD

Eight adults with DSM-IV-diagnosed ADHD (combined type, N = 7; inattentive type, N = 1) were treated with stimulants in open-label form at 8:00 a.m., 12:00 noon, and 4:00 p.m. The mean daily dose was 51 mg of methylphenidate (range, 30-90 mg) in 7 subjects and 30 mg of dextroamphetamine in 1 subject. Actimeters were used to assess nocturnal motor activity during 6 consecutive nights both at baseline and after 3 weeks of treatment. The data were compared with those of 8 matched normal controls.

RESULTS

ADHD patients slept worse and showed significantly higher nocturnal motor activity at baseline compared with controls. No baseline differences between patients and controls were found in sleep latency, number of awakenings, and total time in bed. Changes from baseline to week 3 within the ADHD patients indicated improvement of sleep quality (p = .05) and reduction of Activity Level (p = .10) and Movement Index (p = .07) scores. When within-group changes were compared between ADHD subjects and controls, treatment with stimulants tended to be associated with a reduction of Activity Level (p < .01) and Movement Index (p = .04) scores and improved sleep quality (p = .02) in ADHD patients. Sleep latency, number of awakenings, and total time in bed were unaffected in within-group and between-group analyses.

CONCLUSION

The results should be interpreted cautiously given the open-label design and small sample size. Further study is warranted into the influence of stimulants on sleep in larger samples of ADHD patients by using controlled designs, multiple dose levels, and polysomnographic measures.

Double-blind, placebo-controlled study of single-dose amphetamine formulations in ADHD

OBJECTIVE

To compare the efficacy and time course of single morning doses of Adderall, extended-release, and immediate-release dextroamphetamine sulfate.

METHOD

Thirty-five children with attention-deficit/hyperactivity disorder, combined type, were given Adderall, immediate-release dextroamphetamine, dextroamphetamine Spansules, and placebo in a randomized, double-blind, crossover study. Behavior ratings, locomotor activity measurements, and academic measures were obtained over a period of 8 weeks.

RESULTS

All three drugs exhibited robust efficacy versus placebo on nearly all measures. The effects of dextroamphetamine Spansules were less robust in the morning, particularly compared with Adderall, but they lasted 3 to 6 hours longer, depending on the measure. Although parent behavior ratings and locomotor activity showed improvements up to 12 hours after single doses of all three drugs, the number of math problems attempted and completed correctly 4 hours after dosing were only robustly increased by Spansules.

CONCLUSIONS

Both immediate-release amphetamines demonstrated earlier onset of effects, but dextroamphetamine Spansules showed more sustained effects that were present on a wider range of measures.

Emergence of tics in children with attention deficit hyperactivity disorder treated with stimulant medications

The emergence of tics in children treated with stimulant medication for attention deficit hyperactivity disorder (ADHD) was investigated. A retrospective chart review of the medical records of 555 subjects was performed to examine the emergence of tics in relation to treatment with a stimulant medication, dosage, duration of treatment, and age of subjects. A total of 7.8% of the subjects treated with stimulants developed tics: 8.3% of subjects treated with methylphenidate, 6.3% with dextroamphetamine, and 7.7% with pemoline. The subjects who developed tics were significantly younger than those who did not. Subjects treated with higher doses of stimulant medication were not more likely to develop tics. While the emergence of tics was common, these subjects may have developed tics irrespective of stimulant medication. Controversy remains as to the long-term risk of tics in relation to stimulant medication and to appropriate practice should tics emerge during the course of stimulant medication treatment.

Efficacy of modafinil compared to dextroamphetamine for the treatment of attention deficit hyperactivity disorder in adults

Our objective was to compare the efficacy of the new wake-promoting drug modafinil to that of dextroamphetamine for the treatment of attention deficit hyperactivity disorder (ADHD) in adults. Twenty-two adults who met DSM-IV criteria for ADHD participated in a randomized, double-blind, placebo-controlled, three-phase crossover study comparing placebo, modafinil, and dextroamphetamine for the treatment of ADHD. The twice-daily study medications were titrated to doses of optimum efficacy over 4-7 days and then held constant during the rest of each 2-week treatment phase. Measures of improvement included the DSM-IV ADHD Behavior Checklist for Adults, the Controlled Oral Word Association Test (COWAT, using the letters C, F, and L version), Stroop, and Digit Span (Wechsler Adult Intelligence Scale version). For the 21 (96%) completers, the mean (+/- SD) optimum doses of modafinil and dextroamphetamine were 206.8 mg/day +/- 84.9 and 21.8 mg/day +/- 8.9, respectively. Scores on the DSM-IV ADHD Checklist (p < 0.001) were significantly improved over the placebo condition following treatment with both active medications. Performance on the COWAT (p < 0.05) reached trend levels of significance. Both medications were generally well tolerated. This preliminary study suggests that modafinil may be a viable alternative to conventional stimulants for the treatment of adults with ADHD.

Sudden death of a child treated with imipramine. Case study

Since 1990, there have been seven reported cases of sudden death in children treated with tricyclic antidepressants. This case study describes the sudden death of an additional child (8 years 9 months old, 29 kg in weight) treated with a tricyclic antidepressant, imipramine (100 mg orally, twice daily), and dextroamphetamine (10 mg orally every morning). Prior to death, there were signs of possible cardiovascular abnormalities after treatment was begun with imipramine. The report adds to the concern over the use of tricyclics in children.

Treatment for amphetamine withdrawal

BACKGROUND

Amphetamine withdrawal has been less studied although it is a common problem with a prevalent rate of 87% among amphetamine users. Its symptoms, in particular intense craving, may be a critical factor leading to relapse of amphetamine use. In clinical practice, treatment for cocaine withdrawal has been recommended for the management of amphetamine withdrawal although the pharmacodynamic and pharmacokinetic properties of these two substances are not the same.

OBJECTIVES

To search and determine risks, benefits, and costs of a variety of treatments for the management of amphetamine withdrawal.

SEARCH STRATEGY

Electronic searches of MEDLINE (1966 - December 2000), EMBASE (1980 - February 2001), CINAHL (1982 - January 2001) and Cochrane Controlled Trials Register (Cochrane Library 2000 issue 4) were undertaken. References to the articles obtained by any means were searched.

SELECTION CRITERIA

All relevant randomised controlled trials (RCTs) and controlled clinical trials (CCTs) were included. Participants were people with amphetamine withdrawal, diagnosed by any set of criteria. Any kinds of biological and psychological treatments both alone and combined were examined. A variety of outcomes, for example, number of treatment responders, score changes, were considered.

DATA COLLECTION AND ANALYSIS

Two reviewers evaluated and extracted the data independently. The dichotomous data were extracted on an intention-to-treat basis in which the dropouts were assigned as participants with the worst outcomes. The Relative Risk (RR) with the 95% confidence interval (95% CI) was used to assess the dichotomous data. The Weighted Mean Difference (WMD) with 95% CI was used to assessed the continuous data.

MAIN RESULTS

The results of two studies have shown some benefits of amineptine in the treatment of amphetamine withdrawal. Those benefits can be seen in the respects of discontinuation rate and global state, as measured by Clinical Global Impression Scale. However, no direct benefit of amineptine on amphetamine withdrawal symptoms or craving was shown.

REVIEWER'S CONCLUSIONS

The evidence about the treatment for amphetamine withdrawal is very limited. Amineptine has limited benefits on some amphetamine withdrawal symptoms. Due to a number of reports of amineptine abuse, it has been withdrawn from the market for a few years. At present, no available treatment has been demonstrated to be effective in the treatment of amphetamine withdrawal. The medications that should be considered for further treatment studies may be those with the propensities to increase dopamine, norepinephrine and/or serotonin activities of the brain. Naturalistic studies of amphetamine withdrawal symptoms and course are also crucial for the development of study designs appropriate for further treatment studies of amphetamine withdrawal.

Neuronal degeneration in the limbic system of weanling rats exposed to saline, hyperthermia or d-amphetamine

Neuronal degeneration was detected in the tenia tecta and other regions of the anterior limbic system of male weanling rats 3 days after four doses of 5 mg/kg d-amphetamine (4 x 5 mg/kg AMPH) when seizures occurred during AMPH exposure. Neurodegeneration in the parietal cortex, loss of tyrosine hydroxylase immunoreactivity in the caudate-putamen (CPu) and decreases in CPu tissue dopamine levels in weanlings was much less than those previously observed in adults. The neurotoxicity seen in the parietal cortex and CPu of the weanlings was much less than previously seen in adults even though severe hyperthermia and the behavior of retrograde propulsion occurred during AMPH exposure. Neurodegeneration was not detected in any of the previously mentioned brain regions in controls and weanlings made hyperthermic by a warm environment. However, signs of spontaneous neurodegeneration were seen in the posterior piriform cortex (Pir), posteriolateral cortical amygdaloid nucleus (PLCo), and the amygdalopiriform transition area (APir) of control weanlings. The doses of AMPH and the degree of hyperthermia necessary to induce seizures were substantially lower in weanlings compared to those previously observed in adult rats. Further studies will be necessary to determine if the susceptibility of weanlings to AMPH-induced seizures is related to or dependent on the same processes involved in producing degeneration in the posterior limbic system of saline controls.

Psychostimulants in supportive care

Psychostimulant medications have been used clinically and investigated in psychiatric populations, the medically ill, cancer patients and healthy people. This article discusses the pharmacology of dextroamphetamine, methylphenidate, pemoline (and other psychostimulants such as caffeine and ephedrine), their use in general medicine and cancer care, side effects, and abuse potential. Therapeutic use in children is addressed only insofar as it illustrates facets of their use in adults.

Acute effects of d-amphetamine during the early and late follicular phases of the menstrual cycle in women

Recent preclinical evidence indicates that ovarian hormones, such as estrogen and progesterone, may influence the behavioral effects of psychoactive drugs by interacting directly with neurotransmitter systems in the central nervous system. However, few studies have examined the effects of ovarian hormones on subjective or behavioral responses to psychoactive drugs in humans. In the present study, we assessed the subjective and physiological effects of d-amphetamine during the early and late follicular phases of the menstrual cycle. Nineteen healthy, regularly-cycling women participated in four sessions receiving doses of d-amphetamine (AMPH; 15 mg oral) or placebo during the early and late follicular phases of two menstrual cycles. During the early follicular phase levels of both estrogen and progesterone are low, whereas during the late follicular phase estrogen levels are higher while progesterone remains low. Dependent measures included self-report questionnaires, physiological measures and plasma hormone levels. Most of the subjective and physiological effects of AMPH were not affected by menstrual cycle phase. However, subjects reported greater Unpleasant Stimulation after AMPH, and less Unpleasant Sedation, during the late follicular phase than during the early follicular phase. These results provide limited evidence that higher levels of estrogen during the late follicular phase alter the subjective effects of AMPH in normal, healthy women.

A follow-up pilot study of objective measures in children with attention deficit hyperactivity disorder

OBJECTIVES

Attention deficit hyperactivity disorder (ADHD) is a common childhood problem requiring stimulant medications in a significant proportion of cases. The aim of this pilot study was to assess the effects of prolonged stimulant medication therapy on a continuous performance test, the Test of Variables of Attention (TOVA), which measures objectively features of ADHD.

METHODS

Eighteen children aged 8 to 16 years who were diagnosed with ADHD, based on the Diagnostic and Statistical Manual of Mental Disorders 4th edn criteria, were included in the study. Assessment on a continuous performance test (TOVA) was performed initially and the children were administered stimulant medications for at least 12 months. The medications were stopped for 1 week, followed by a repeat TOVA assessment which was compared to the initial TOVA assessment.

RESULTS

Follow up TOVA scores showed a significant improvement in mean commission errors (impulsivity) after the stimulant medication therapy. No significant improvement was found in omission errors (inattention), response time and variability. There was a significant positive correlation between commission and omission scores (P value 0.0001).

CONCLUSIONS

The results of this pilot study indicate that there is objective improvement in impulsivity in children with ADHD after a prolonged period of stimulant medication therapy. The study suggests that it would be useful to perform formal studies to investigate this further and also to assess the role of continuous performance test (TOVA) as a method for monitoring the need for ongoing therapy.

Psychostimulants and psychiatrists: the Trent Adult Psychiatry Psychostimulant Survey

This study reports upon the results of a postal questionnaire survey of 107 adult psychiatrists which investigated their current use of psychostimulant pharmacotherapy and their attitudes towards the diagnostic status of attention-deficit hyperactivity disorder (ADHD) in adulthood. Of the 88 respondents, only a minority of 11 (12.5%) used psychostimulants in their usual practice, albeit very infrequently (one or two prescriptions per year on average). Methylphenidate hydrochloride ('Ritalin') was the prescribers' most popular agent and 'narcolepsy' was the most frequently cited clinical indication for psychostimulants. ADHD appeared to represent only a very small area of current clinical activity and a minority of clinicians expressed the view that it did not exist in adults. It is concluded that psychostimulant therapy is relatively undeveloped in British adult psychiatry and that the clinical speciality generally appears to be unprepared for the growing numbers of adolescents with ADHD who are currently managed by child psychiatrists and who may require ongoing psychiatric care, including psychostimulant therapy.

Psychostimulants, adult attention deficit hyperactivity disorder and morbid jealousy

OBJECTIVE

This paper aims to discuss the relationship between morbid jealousy, stalking behaviour, and psychodynamic issues. Comment will be made on the risk associated with diagnosis of adult attention deficit hyperactivity disorder (ADHD) and use of psychostimulants.

CLINICAL PICTURE

A man born in the former Yugoslavia charged with stalking was referred for assessment. He presented with a history of treatment for ADHD with dexamphetamine and delusions regarding his wife's fidelity.

TREATMENT

The patient was treated with neuroleptics and counselling for himself and his family.

OUTCOME

The patient was returned to the community. He separated from his wife but retains the abnormal belief.

CONCLUSIONS

The diagnosis of adult ADHD appears to be increasing in Western Australia. Treatment with stimulants is common. The misdiagnosis of ADHD and consequent misuse of stimulants, can lead to the development of morbid jealousy, stalking behaviour and arrest.