A double-blind trial with baclofen (Lioresal) and diazepam in spasticity due to multiple sclerosis

Pharmacological and Non-pharmacological Approaches for the Management of Neuropathic Pain in Multiple Sclerosis

Multiple sclerosis is a chronic inflammatory disease that affects the central nervous system and can cause various types of pain including ongoing extremity pain, Lhermitte's phenomenon, trigeminal neuralgia, and mixed pain. Neuropathic pain is a major concern for individuals with multiple sclerosis as it is directly linked to myelin damage in the central nervous system and the management of neuropathic pain in multiple sclerosis is challenging as the options available have limited efficacy and can cause unpleasant side effects. The literature search was conducted across two databases, PubMed, and Google Scholar. Eligible studies included clinical trials, observational studies, meta-analyses, systematic reviews, and narrative reviews. The objective of this article is to provide an overview of literature on pharmacological and non-pharmacological strategies employed in the management of neuropathic pain in multiple sclerosis. Pharmacological options include cannabinoids, muscle relaxants (tizanidine, baclofen, dantrolene), anticonvulsants (benzodiazepines, gabapentin, phenytoin, carbamazepine, lamotrigine), antidepressants (duloxetine, venlafaxine, tricyclic antidepressants), opioids (naltrexone), and botulinum toxin variants, which have evidence from various clinical trials. Non-pharmacological approaches for trigeminal neuralgia may include neurosurgical methods. Non-invasive methods, physical therapy, and psychotherapy (cognitive behavioral therapy, acceptance and commitment therapy and mindfulness-based stress reduction) may be recommended for patients with neuropathic pain in multiple sclerosis. The choice of treatment depends on the severity and type of pain as well as other factors, such as patient preferences and comorbidities. There is a pressing need for healthcare professionals and researchers to prioritize the development of better strategies for managing multiple sclerosis-induced neuropathic pain.

Classics in Chemical Neuroscience: Baclofen

Baclofen, β-(4-chlorophenyl)-γ-aminobutyric acid, holds a unique position in neuroscience, remaining the only U.S. Food and Drug Administration (FDA) approved GABA_B agonist. While intended to be a more brain penetrant, i.e, ability to cross the blood-brain barrier (BBB), version of GABA (γ-aminobutyric acid) for the potential treatment of epilepsy, baclofen's highly efficacious muscle relaxant properties led to its approval, as a racemate, for the treatment of spasticity. Interestingly, baclofen received FDA approval before its receptor, GABA_B, was discovered and its exact mechanism of action was known. In recent times, baclofen has a myriad of off-label uses, with the treatment for alcohol abuse and drug addiction garnering a great deal of attention. This Review aims to capture the >60 year legacy of baclofen by walking through the history, pharmacology, synthesis, drug metabolism, routes of administration, and societal impact of this Classic in chemical neuroscience.

A mixed treatment comparison on efficacy and safety of treatments for spasticity caused by multiple sclerosis: a systematic review and network meta-analysis

OBJECTIVES

This study is aimed at providing a quantitative evaluation on different therapies of spasticity caused by multiple sclerosis.

DATA SOURCES

PubMed and Embase database.

REVIEW METHODS

We searched for randomized controlled trials that met the requirements. Percentages of improved patients' spasticity scale, mild adverse effect and severe adverse effect were extracted as outcomes. The forest plots accompanied with surface under the cumulative ranking curves were used to reveal the efficacy and safety of these therapies.

RESULTS

In all, 23 randomized controlled trials with a total of 2720 patients were included in our study. Cannabinoids and botulinum toxin had shown a significantly better efficacy than placebo in the percentage of improved patients. Botulinum toxin also showed such significant difference compared with tizanidine and baclofen. No significant difference was found in spasticity scale. Cannabinoids, tizanidine and diazepam had significantly more mild adverse effect reports than placebo. Surface under the cumulative ranking curves suggested that cannabinoids, botulinum toxin and transcutaneous electric nerve stimulation were preferable therapies.

CONCLUSIONS

We recommended botulinum toxin as the optimal intervention for multiple sclerosis-related spasticity. Cannabinoids and transcutaneous electric nerve stimulation could also be considered as multiple sclerosis-related spasticity treatments but their safety remained to be verified.

Pharmacological management of spasticity in multiple sclerosis: Systematic review and consensus paper

Background and objectives:

Treatment of spasticity poses a major challenge given the complex clinical presentation and variable efficacy and safety profiles of available drugs. We present a systematic review of the pharmacological treatment of spasticity in multiple sclerosis (MS) patients.

Methods:

Controlled trials and observational studies were identified. Scientific evidence was evaluated according to pre-specified levels of certainty.

Results:

The evidence supports the use of baclofen, tizanidine and gabapentin as first-line options. Diazepam or dantrolene could be considered if no clinical improvement is seen with the previous drugs. Nabiximols has a positive effect when used as add-on therapy in patients with poor response and/or tolerance to first-line oral treatments. Despite limited evidence, intrathecal baclofen and intrathecal phenol show a positive effect in severe spasticity and suboptimal response to oral drugs.

Conclusion:

The available studies on spasticity treatment offer some insight to guide clinical practice but are of variable methodological quality. Large, well-designed trials are needed to confirm the effectiveness of antispasticity agents and to produce evidence-based treatment algorithms.

Effect of the Intrathecal Baclofen Screening Test on the Spatiotemporal Gait Motion Parameters of Patients with Cervical Spinal Cord Injuries Who Exhibited Diffuse Spasticity: A Report of Three Cases

We examine the quantitative changes in the gait motion of patients with cervical spinal cord injuries (CSCIs) before and after the intrathecal baclofen (ITB) screening test. The subjects were three patients with CSCI, who exhibited spasticity in the lower extremities. They could all walk 10 or more meters with/without aids. All patients were subjected to the ITB screening test, in which they had gabalon (50 μg) injected into their spinal column via paramedian puncture at the L3–4 level. The subjects had their ankle clonus; patellar tendon reflex; and modified Ashworth scale, Berg balance scale, Spinal Cord Independence Measure, and 10 -meter walk test (10MWT) assessed before and 5 hours after the ITB screening test. At 5 hours after the ITB screening test, all of the patients exhibited decreased spasticity in static position, and improved balance. There were no differences in the abilities of any of the patients to perform ADL. One patient did not change the spatiotemporal gait motion parameters (walking time, step count, and step length in the 10MW T). Therefore, the pomp implantation for ITB therapy was not performed. Two patients who had suffered CSCI more than 20 years ago exhibited a reduced walking time, increased step count, and step length. Out of the two patients one received the pomp of implantation after ITB screening test, and the other was planned to operate. The spatiotemporal gait motion parameters might be one of the useful tests to decide the pomp implantation for CSCI patients who hope improvement of gait ability.

Using conditioned place preference to identify relapse prevention medications

Stimuli, including contexts, which predict the availability or onset of a drug effect, can acquire conditioned incentive motivational properties. These conditioned properties endure after withdrawal, and can promote drug-seeking which may result in relapse. Conditioned place preference (CPP) assesses the associations between drugs and the context in which they are experienced. Here, we review the potential utility of CPP procedures in rodents and humans to evaluate medications that target conditioned drug-seeking responses. We discuss the translational potential of the CPP procedure from rodents to humans, and review findings with FDA-approved treatments that support the use of CPP to develop relapse-reduction medications. We also discuss challenges and methodological questions in applying the CPP procedure to this purpose. We argue that an efficient and valid CPP procedure in humans may reduce the burden of full clinical trials with drug-abusing patients that are currently required for testing promising treatments.

Symptomatic management in multiple sclerosis

The development of immunomodulatory therapies for multiple sclerosis (MS) has had significant impact in altering the natural history of the disease. Although these agents reduce relapse rate and MRI-associated disease activity, they are only partially effective and do not ameliorate irreversible axonal injury, which produces much of the symptomatic burden of MS. Treatment of MS-associated symptoms remains an essential cornerstone of comprehensive care of patients with MS and, arguably, more favorably enhances quality of life than do the disease-modifying medications. This article reviews strategies of symptom management in patients with MS.

Rehabilitation in practice: Spasticity management

This series of articles for rehabilitation in practice aims to cover a knowledge element of the rehabilitation medicine curriculum. Nevertheless they are intended to be of interest to a multidisciplinary audience. The competency addressed in this article is 'The trainee consistently demonstrates a knowledge of the pathophysiology of various specific impairments including spasticity'. Spasticity is an extremely common feature of chronic neurological conditions and, if badly managed, it can result in pain, contractures and pressure sores, all of which can impact on function. It is therefore essential that a multidisciplinary management strategy is in place to help the individual manage their particular situation through education with timely access to interventions including instigation of a physical management programme and medication such as baclofen, tizanidine, dantrolene, benzodiazepines and gabapentin. Further treatment options for focal spasticity are botulinum toxin and phenol nerve blocks or intrathecal baclofen or phenol for predominant lower limb spasticity. Ongoing assessment with the use of appropriate outcome measures can both guide choice of treatment and monitor efficacy.

The GABA B agonist baclofen reduces cigarette consumption in a preliminary double-blind placebo-controlled smoking reduction study

The surge in dopamine in ventral striatal regions in response to drugs of abuse and drug-associated stimuli is a final common pathway of addiction processes. GABA B agonists exert their effects indirectly, by quieting dopaminergic afferents. The ability of the GABA B agonist, baclofen to ameliorate nicotine and drug motivated behavior is established within the animal literature, however its potential to do so in humans is understudied, particularly with respect to its possible utility as a smoking cessation agent. We conducted a nine-week double-blind placebo-controlled pilot trial of baclofen for smoking reduction (N=30/group) in smokers contemplating, but not quite ready to quit. Baclofen was titrated upwards to 20mg q.i.d. over a period of twelve days. The primary outcome measure was the number of cigarettes smoked per day (CPD). A significant group by time effect of medication was observed. Baclofen was superior to placebo in reducing CPD (beta=0.01, t=1.97, p<0.05). The most common side effect reported during baclofen treatment is transient drowsiness, however there were no differences between groups in mild, moderate, or severe sedation. Craving was significantly lowered at end of treatment in all smokers (p<0.02). Retention did not differ between groups. In line with a multitude of preclinical studies examining the effects of baclofen on drug-motivated behavior, baclofen reduced CPD. In agreement with other studies examining craving and drug use, reductions in CPD were accompanied by a reduction in craving, a major motivator underlying continued smoking and relapse. These preliminary results demonstrate provisional evidence of the utility of baclofen to aid in smoking cessation and indicate further investigation.

Managing the symptoms of multiple sclerosis: a multimodal approach

BACKGROUND

Patients with multiple sclerosis (MS) may experience numerous symptoms, including spasticity, fatigue, cognitive dysfunction, depression, bladder dysfunction, bowel dysfunction, sexual dysfunction, and pain.

OBJECTIVE

This article reviews the pharmacologic and nonpharmacologic interventions used to manage the symptoms of MS and discusses how interventions for a particular MS symptom may have an impact on other symptoms.

METHODS

The English-language literature was reviewed through November 2005 using MEDLINE and the Cochrane Database of Systematic Reviews, with no restriction on year. The search terms included multiple sclerosis, disease-modifying therapies, adverse events, and combinations of multiple sclerosis with terms such as spasticity, fatigue, depression, mood disorders, pain, bladder dysfunction, bowel dysfunction, sexual dysfunction, cognitive dysfunction, and quality of life.

RESULTS

The numerous options for the treatment of MS symptoms have shown varying degrees of efficacy and tolerability. Certain symptoms, if left untreated, may precipitate exacerbation of others. For example, spasticity may lead to pain and bladder and bowel dysfunction, whereas fatigue can compromise cognitive function. Similarly, the adverse effects of treatments for certain symptoms may further compromise other aspects of function. For example, the use of antidepressants may lead to sexual dysfunction, and treatments for spasticity and pain may cause sedation, which can worsen fatigue, cognitive dysfunction, and depressed mood.

CONCLUSIONS

MS is associated with numerous symptoms that can be adversely affected by each other and by therapeutic interventions. Careful clinical monitoring and individualization of pharmacologic and non-pharmacologic therapies are recommended to manage the symptoms of MS, with the goals of improving or maintaining function and preserving the patient's quality of life.

Multiple Sclerosis and Spasticity

Spasticity is a common impairment in MS. It can result in significant medical complications and is associated with increased disability. Treatment strategies include skilled rehabilitation strategies, neuromuscular blocks, oral agents, intrathecal management, and surgery. Rehabilitation strategies are central, whereas other strategies are added based on the level of impairment and functional loss. Treatment strategies for spasticity management are far from optimal and are complicated in MS as a result of lesions in the brain and the spinal cord. Pharmaceutical management in MS is complicated by the numerous secondary impairments in MS and its associated polypharmacy.Head-to-head studies of the various agents are rare. The studies that exist are small and do not point to any one strategy over another. Although management is difficult, it is essential for the health, functional status, and well-being of the individual who has MS. Providers must use well-developed clinical skills to arrive at optimal individualized treatment programs and monitor them frequently. For spasticity that is unresponsive, referral to a MS Center with a spasticity program is ideal.

A benefit-risk assessment of baclofen in severe spinal spasticity

Baclofen is used for treatment of the spasticity of spinal origin that is a common sequela of spinal cord injury and multiple sclerosis; spasticity occurs in about 50% of patients affected by these disorders. In open-label studies of oral baclofen, the drug improved spasticity in 70-87% of patients; additionally, improvement in spasms was reported in 75-96% of patients. In double-blind, crossover, placebo-controlled trials, baclofen was reported to be effective, producing statistically significant improvements in spasticity. Tizanidine is the antispasticity drug that has been most widely compared with oral baclofen; studies have generally found the two drugs to have equivalent efficacy. However, tizanidine has better tolerability, in particular weakness was reported to be occur less frequently with tizanidine than with baclofen. The main adverse effects of oral baclofen include: sedation or somnolence, excessive weakness, vertigo and psychological disturbances. The incidence of adverse effects is reported to range from 10% to 75%. The majority of adverse effects are not severe; most are dose related, transient and/or reversible. The main risks of oral baclofen administration are related to withdrawal: seizures, psychic symptoms and hyperthermia can occur. These symptoms improve after the reintroduction of baclofen, usually without sequelae. When not related to withdrawal; these symptoms mainly present in patients with brain damage and in the elderly. The limited data on baclofen toxicity in patients with renal disease suggest that administration of the drug in these persons may carry an unnecessarily high risk. Intrathecal baclofen is indicated for use in patients with spasticity of spinal origin unresponsive to treatment with maximum doses of oral baclofen, tizanidine and/or dantrolene. The benefits of continuous intrathecal baclofen infusion have been demonstrated: >80% and >65% of patients have improvement in tone and spasms, respectively. The main risks of intrathecal baclofen infusion are symptoms related to overdose or withdrawal; the latter is more important because of the associated severe effects on clinical status and the possibility of death, but it is responsive to rapid treatment. Overdose primarily arises from drug test doses or human error during refill and programming of the pump, and withdrawal most commonly occurs as a result of a problem with the delivery system. Since the adverse consequences do not exceed the benefits of oral and intrathecal baclofen for patients with spinal spasticity, the benefit/risk assessment is favourable.

Comparative efficacy and safety of skeletal muscle relaxants for spasticity and musculoskeletal conditions: a systematic review

Skeletal muscle relaxants are a heterogeneous group of medications used to treat two different types of underlying conditions: spasticity from upper motor neuron syndromes and muscular pain or spasms from peripheral musculoskeletal conditions. Although widely used for these indications, there appear to be gaps in our understanding of the comparative efficacy and safety of different skeletal muscle relaxants. This systematic review summarizes and assesses the evidence for the comparative efficacy and safety of skeletal muscle relaxants for spasticity and musculoskeletal conditions. Randomized trials (for comparative efficacy and adverse events) and observational studies (for adverse events only) that included oral medications classified as skeletal muscle relaxants by the FDA were sought using electronic databases, reference lists, and pharmaceutical company submissions. Searches were performed through January 2003. The validity of each included study was assessed using a data abstraction form and predefined criteria. An overall grade was allocated for the body of evidence for each key question. A total of 101 randomized trials were included in this review. No randomized trial was rated good quality, and there was little evidence of rigorous adverse event assessment in included trials or observational studies. There is fair evidence that baclofen, tizanidine, and dantrolene are effective compared to placebo in patients with spasticity (primarily multiple sclerosis). There is fair evidence that baclofen and tizanidine are roughly equivalent for efficacy in patients with spasticity, but insufficient evidence to determine the efficacy of dantrolene compared to baclofen or tizanidine. There is fair evidence that although the overall rate of adverse effects between tizanidine and baclofen is similar, tizanidine is associated with more dry mouth and baclofen with more weakness. There is fair evidence that cyclobenzaprine, carisoprodol, orphenadrine, and tizanidine are effective compared to placebo in patients with musculoskeletal conditions (primarily acute back or neck pain). Cyclobenzaprine has been evaluated in the most clinical trials and has consistently been found to be effective. There is very limited or inconsistent data regarding the effectiveness of metaxalone, methocarbamol, chlorzoxazone, baclofen, or dantrolene compared to placebo in patients with musculoskeletal conditions. There is insufficient evidence to determine the relative efficacy or safety of cyclobenzaprine, carisoprodol, orphenadrine, tizanidine, metaxalone, methocarbamol, and chlorzoxazone. Dantrolene, and to a lesser degree chlorzoxazone, have been associated with rare serious hepatotoxicity.

Pain and spasticity after spinal cord injury: mechanisms and treatment

STUDY DESIGN

A comprehensive survey of literature on the proposed mechanisms and treatment of pain and spasticity after spinal cord injury (SCI) was completed.

OBJECTIVES

To define the current understanding of these entities and to review various treatment options.

SUMMARY OF BACKGROUND DATA

The neurophysiologic basis of spasticity after SCI is well established. The mechanism of neuropathic pain after SCI remains conjectural, although considerable new data, much of it from animal models, now add to our understanding of this condition.

METHODS

A comprehensive search and review of the published literature was undertaken.

RESULTS

Treatment options for spasticity are effective and include oral medication (baclofen, tizanidine), intrathecal baclofen, and rarely, surgical rhizotomy or myelotomy. Selected patients with post-SCI pain can respond to surgical myelotomy (DREZ lesions) or intrathecal agents (e.g., morphine + clonidine), but the majority continue to suffer.

CONCLUSIONS

Medical and surgical treatments for spasticity are established and highly successful. Management of post-SCI pain remains a clinical challenge, as there is no uniformly successful medical or surgical treatment.

Drugs used to treat spasticity

Spasticity is a common and disabling symptom for many patients with upper motor neuron dysfunction. It results from interruption of inhibitory descending spinal motor pathways, and although the pathophysiology of spasticity is poorly understood, the final common pathway is overactivity of the alpha motor neuron. Therapy for spasticity is symptomatic with the aim of increasing functional capacity and relieving discomfort. Any approach to treatment should be multidisciplinary, including physical therapy, and possibly surgery, as well as pharmacotherapy. It is important that treatment be tailored to the individual patient, and that both patient and care giver have realistic expectations. Pharmacotherapy is generally initiated at low dosages and then gradually increased in an attempt to avoid adverse effects. Optimal therapy is the lowest effective dosage. Baclofen, diazepam, tizanidine and dantrolene are currently approved for use in patients with spasticity. In addition, clonidine (usually as combination therapy), gabapentin and botulinum toxin have shown efficacy, however, more studies are required to confirm their place in therapy. Intrathecal baclofen, via a surgically implanted pump and reservoir, may provide relief in patients with refractory severe spasticity.

Anti-spasticity agents for multiple sclerosis

BACKGROUND

Spasticity is a common problem in MS patients causing pain, spasms, loss of function and difficulties in nursing care. A variety of oral and parenteral medications are available.

OBJECTIVES

To assess the absolute and comparative efficacy and tolerability of anti-spasticity agents in multiple sclerosis (MS) patients.

SEARCH STRATEGY

Randomised controlled trials (RCTs) of anti-spasticity agents were identified using MEDLINE, EMBASE, bibliographies of relevant articles, personal communication, manual searches of relevant journals and information from drug companies.

SELECTION CRITERIA

Double-blind, randomised controlled trials (either placebo-controlled or comparative studies) of at least seven days duration.

DATA COLLECTION AND ANALYSIS

Two independent reviewers extracted data and the findings of the trials were summarised. Missing data were collected by correspondence with principal investigators. A meta-analysis was not performed due to the inadequacy of outcome measures and methodological problems with the studies reviewed.

MAIN RESULTS

Twenty-three placebo-controlled studies (using baclofen, dantrolene, tizanidine, botulinum toxin, vigabatrin, prazepam and threonine) and thirteen comparative studies met the selection criteria. Only thirteen of these studies used the Ashworth scale, of which only three of the six placebo-controlled trials and none of the seven comparative studies showed a statistically significant difference between test drugs. Spasms, other symptoms and overall impressions were only assessed using unvalidated scores and results of functional assessments were inconclusive.

REVIEWER'S CONCLUSIONS

The absolute and comparative efficacy and tolerability of anti-spasticity agents in multiple sclerosis is poorly documented and no recommendations can be made to guide prescribing. The rationale for treating features of the upper motor neurone syndrome must be better understood and sensitive, validated spasticity measures need to be developed.

Treatment of spasticity with repetitive magnetic stimulation; a double-blind placebo-controlled study

The effect of repetitive magnetic stimulation on spasticity was evaluated in 38 patients with multiple sclerosis in a double-blind placebo-controlled study. One group was treated with repetitive magnetic stimulation (n = 21) and the other group with sham stimulation (n = 17). Both groups were treated twice daily for 7 consecutive days. Primary end-points of the study were changes in the patients self-score, in clinical spasticity score, and in the stretch reflex threshold. The self-score of ease of daily day activities improved by 22% (P = 0.007) after treatment and by 29% (P = 0.004) after sham stimulation. The clinical spasticity score improved -3.3 +/- 4.7 arbitrary unit (AU) in treated patients and 0.7 +/- 2.5 AU in sham stimulation (P = 0.003). The stretch reflex threshold increased 4.3 +/- 7.5 deg/s in treated patients and -3.8 +/- 9.7 deg/s in sham stimulation (P = 0.001). The data presented in this study supports the idea that repetitive magnetic stimulation has an antispastic effect in multiple sclerosis. Future studies should clarify the optimal treatment regimen.

Gait analysis of spinal cord injured subjects: effects of injury level and spasticity

OBJECTIVE

To identify abnormalities in the gait of spinal cord injured (SCI) subjects, particularly in relation to injury level and spasticity.

DESIGN

Case-control study comparing the gait of SCI individuals with matched controls. Video-motion analysis was used to collect data on temporal and kinematic variables. Spasticity was assessed using the Ashworth score and pendulum test. Data regarding age, height, weight, mechanism, and level of injury were also collected.

SETTING

Spinal cord injury clinic of a tertiary care hospital.

PARTICIPANTS

Twenty-seven SCI individuals volunteered to participate in the study. All had retained walking ability (Frankel D) and could ambulate independently for a minimum of 10m with or without walking aids. Individuals with cauda equina injuries were excluded from the study. Age, gender, etiology of injury, and interval since injury were not used as exclusion criteria. Ten age-, sex-, and anthropomorphically matched controls were also recruited.

RESULTS

Subjects with thoracic injures demonstrated reduced cadence, forward velocity, and knee angular velocity, whereas lumbar injuries resulted in reduced stride length and ankle velocities. These differences were statistically significant (p < .05). Gait in individuals with cervical injuries was not significantly different.

CONCLUSIONS

Kinematic gait analysis is a sensitive means of quantifying gait abnormalities. Spasticity and injury level determine the pattern of abnormality in gait after spinal cord injury.

Reduction of spastic hypertonia in patients with spinal cord injury: a double-blind comparison of intravenous orphenadrine citrate and placebo

Spasticity is one of the major problems affecting the outcome of rehabilitation in paraplegic patients. Orphenadrine citrate possesses an effective muscle relaxant action in many pathologies. Nevertheless, despite a recognized central site of action, no controlled data are available on its use in the treatment of spastic hypertonia in patients with spinal cord injuries. Therefore, the effect of intravenous administration of 60mg of orphenadrine citrate versus placebo on spastic hypertonia after spinal cord injury was studied in 11 patients. The threshold of the flexion reflex of the lower limb was studied as a neurophysiological correlate of spastic hypertonia. Clinical assessment was made using the Ashworth Spasticity Scale. The threshold, expressed in mAmp, was studied for 60 minutes after the treatment. A significant difference was found using the active drug compared with placebo (p < 0.0001). In 9 patients, the reduction of the abnormal flexion responses after orphenadrine appeared to begin only after 30 minutes. In one patient the onset of the therapeutic effect was early but weak. One patient with severe spastic hypertonia leading to triple flexion when the limb was manipulated did not gain any relief with orphenadrine. The clinical and neurophysiological results suggest an efficacy of orphenadrine citrate in the control of spastic hypertonia in paraplegics. This could be relevant in the rehabilitation strategy, although further studies are needed on the duration of its action.

Intrathecal baclofen therapy for adults with spinal spasticity: therapeutic efficacy and effect on hospital admissions

A prospective trial to demonstrate the efficacy of intrathecal baclofen therapy by implanted pump for adults with spasticity due to spinal cord injury or multiple sclerosis was initiated in our hospital. Of the 140 patients assessed, 7 met the following criteria for inclusion in the study: a modified Ashworth score > 3, a spasm frequency score > 2, and an inadequate response to oral anti-spasticity drugs, (i.e., baclofen, clonidine and cyproheptadine). All patients responded to intrathecal bolus injection of baclofen in the double blind, placebo-controlled screening phase (mean bolus dose = 42.8 micrograms). Programmable Medtronic pumps were implanted in 4 patients while 3 patients received non-programmable Infusaid pumps. Post-implantation, a marked decrease in spasticity occurred with a significant reduction of the Ashworth score (mean = 1.8, p < .005), a reduced spasm score (mean = 0.8, p < .005), and an improved leg swing in the pendulum test. These effects were maintained during a follow-up of 24-41 months (average infusion dose = 218.7 micrograms/day). The gross cost-savings due to reduced hospitalizations related to spasticity was calculated by comparing the cost for the two year period before pump implantation to the same period after treatment for 6 of the 7 patients. The cost of in-hospital implantation as well as the cost of the pumps were deducted from the gross savings. There was a net cost-saving of $153,120. Our findings agree with the reported efficacy and safety of intrathecal baclofen treatment, and illustrate the cost-effectiveness of this treatment.

Treatment of spasticity in children with low dose benzodiazepine

In an attempt to investigate whether benzodiazepines at low dosage have a significant effect in reducing spasticity among children with cerebral palsy, we carried out a double-blind, placebo-controlled, cross-over study. Twelve children with either spastic diplegia or hemiplegia participated in this study. The mean age was 14 years. The restraint of passive knee movements was determined with a dynamic dynamometer and spastic stretch reflexes were measured as EMG activity in muscles stretched. Clonazepam was given at low dosage (0.02 mg/kg body weight). In each child measurements of passive restraint were made on 2 different days immediately before and 3 h after an i.m. injection of either clonazepam or placebo in randomized order. Clonazepam significantly reduced spastic restraint (P < 0.001) compared to non-significant reduction with placebo. The mean plasma concentration of clonazepam at time of spasticity evaluation was 21 mmol/l which is in the low dose range, far below conventional doses. The study thus shows a positive effect of low dose clonazepam in reducing spasticity in children when given as a single dose.

Effect of skeletal muscle relaxants on bladder smooth muscle

The present study was conducted to determine the effects of skeletal muscle relaxants on contractions of bladder smooth muscle. Rat, rabbit and human bladder muscle strips were incubated in a 50 ml. organ bath filled with physiological salt solution, aerated with 95 per cent O2, 5 per cent CO2 and maintained at 37C. Contractions were induced both electrically and with acetylcholine. Contractile strength was measured before and after 30 to 70 minute incubations with diazepam (0.25 to 1.0 microgram./ml.), dantrolene sodium (4 micrograms./ml.) or baclofen (4 micrograms./ml.). Neither baclofen nor dantrolene sodium had any effect (p greater than 0.3) on electrically or acetylcholine-induced contractions in any of the 3 species tested but diazepam potentiated both electrically induced (115 per cent of predrug contractile strength, p less than 0.05) and acetylcholine-induced (122 per cent of predrug contractile strength, p less than 0.01) contractions of rat, but not rabbit or human, bladder muscle. In rabbits diazepam significantly reduced maximal bladder pressures in vivo (p less than 0.05) but had no effect on bladder capacity. Dantrolene sodium had no effect on rabbit bladder pressure or capacity in vivo. While diazepam is thought to exert its effects on skeletal muscle through CNS inhibition, these results suggest that diazepam may affect rat but not rabbit or human bladder smooth muscle directly.

The use of baclofen in treatment of spasticity in multiple sclerosis

Baclofen was used in a double-blind crossover placebo-controlled trial to treat spasticity in patients with multiple sclerosis (MS). While on Baclofen, patients obtained a significant (p less than 0.001) reduction in spasticity compared to controls. The drug was particularly effective in alleviating flexor and extensors spasms, as well as their associated pain. Side effects were common in this study, but were usually well tolerated by the patients. The commonest side effects were sedation, nausea and vomiting. There were no changes in hepatic, renal, or hematological function in any patients. Increase weakness due to loss of spasticity for support was also a fairly common complaint. The drug seems best indicated in patients in whom spasticity is not required for support or other activities of daily living. Careful monitoring of the patient is essential for effective use of this drug.

[Clinico-quatitative evaluation of the action of Ciba 34.647-Ba on spasticity]

Using the clinical quantification of the neurologic symptomatology the authors made observations and avaliated the action of Ciba 34.647-Ba, a GABA derivative, in 12 patients suffering from spasticity and motor incapacity due to spinal cord lesions. The results are reported emphasizing the effects of the drug on the main components of spasticity (hypertonus, hyperactivity of the deep reflexes, clonus and automatisms). Some theories explaining the mechanism of action of the drug are mentioned. References are made about doses, duration of action, tolerance and side-effects.

Comparison of dantrolene sodium and diazepam in the treatment of spasticity

The effects of dantrolene sodium and diazepam were compared in a double crossover study of 42 patients with spasticity due to stable multiple sclerosis. Both drugs reduced the findings of spasticity, clonus, and hyperreflexia, and the complaints of muscle stiffness and cramping. Each drug had different side effects which suggest indications and contraindications for its use in spastic patients.