Progabide treatment in severe epilepsy: a double-blind cross-over trial versus placebo

Twenty therapy-resistant epileptic patients entered a double-blind, randomized, two-period, cross-over trial comparing progabide (19.3-36 mg/kg/day) and placebo as add-on drugs to standard therapy. Each period lasted 6 weeks with a gradual crossover during 4 days. Five patients were dropped because of reasons unrelated to treatment. Among the 15 patients who completed the study, seven had partial, six primary generalized, and two secondary generalized epilepsies. Preexisting antiepileptic drugs (AEDs) ranging from one to three per patient (mean 2.2 AEDs/patient) were maintained unchanged during the trial. Efficacy was assessed biweekly by means of total seizure counts, counts of each seizure type, and global clinical judgment. At the same time intervals, safety was assessed by means of reports of adverse events, clinical and neurological examination, laboratory tests, and measurement of plasma concentrations of progabide and associated AEDs. According to the clinical global judgment, eight patients were considered improved during progabide treatment. Seizures were reduced in 14 of 15 patients during the progabide as compared with the placebo period. During the progabide period, the reduction of the total seizure count was 45 and 58% in two patients and 88-97% in six patients. A significant reduction of the total seizure number was observed in the progabide period as compared with the placebo period, both in the whole patient group (p less than 0.01) and in the two subgroups of patients with generalized (p less than 0.01) and partial (p less than 0.05) epilepsies.(ABSTRACT TRUNCATED AT 250 WORDS)     

Residual effects of zolpidem,triazolam, rilmazafone and placebo in healthy elderly subjects: a randomized double-blind study

With current hypnotic agents, next-day residual effects are a common problem. The purpose of the present study was to evaluate the residual effects of the commercially available hypnotics – zolpidem, triazolam, and rilmazafone – on the physical and cognitive functions of healthy elderly people in the early morning and the day following drug administration.In this study, the next-day residual effects of zolpidem, triazolam, and rilmazafone, following bedtime dosing in elderly subjects, were evaluated. Women (n = 11) and men (n = 2) aged 60–70 years received a single dose (at 23:00) of one of these, zolpidem 5 mg, triazolam 0.125 mg, rilmazafone 1 mg and placebo in a randomized, double-blind, crossover design. Measures of objective parameters and psychomotor performances (Timed up and Go test, Functional Reach Test, body sway test, critical flicker fusion test, simple discrimination reaction test, short-term memory test) and subjective ratings were obtained at 04:00, 07:00, and the next time of the day.All hypnotics were generally well tolerated; there were no serious adverse side effects and no subjects discontinued the evaluations. Compared to placebo, zolpidem and rilmazafone had good results on the Functional Reach Test. Although subjective assessments tended to be poor in the early morning, rilmazafone significantly improved the body sway test in the other hypnotics.A single dose of zolpidem 5 mg and triazolam 0.125 mg did not have any next-day residual effects on healthy elderly subjects. Residual effects appeared to be related to the compound's half-life and the dose used. Rilmazafone 1 mg exhibited steadiness in static and dynamic balance and seemed to be more favorable for the elderly with early morning awakening.     

Bornaprine vs placebo in Parkinson disease: double-blind controlled cross-over trial in 30 patients

The study covers 30 patients with idiopathic Parkinson disease, 13 men and 17 women, aged betwen 50 and 70, on stabilized L-Dopa and/or bromocriptine, which failed to ensure adequate control of the symptoms, especially tremor. To this regimen was added Bornaprine/placebo in randomized sequence. The patients were tested according to the Webster Rating Scale before, during and after each stage of the treatment. Statistical analysis of the results showed the superiority of Bornaprine over the placebo in reducing tremor (p<0.01) and, to a lesser degree, some other parkinsonian symptoms. No noteworthy side effects were found apart from dryness of the mouth, which was more frequent with Bornaprine.

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Sommario Sono stati esaminati 30 pazienti affetti da morbo di Parkinson idiopatico, di cui 13 maschi e 17 femmine, di età compresa tra 50 edi i 70 anni, in terapia stabilizzata con L-Dopa o con Bromocriptina o con entrambe. In tutti i soggetti, questi farmaci non consentivano un adeguato controllo della sintomatologia, con particolare riferimento al tremore. Lasciando invariata la terapia in atto, si è somministrato Bornaprine od und placebo identico, secondo una sequenza randomizzata, in doppio cieco con cross-over. I pazienti sono stati esaminati per mezzo della Webster Rating Scale a tempi predeterminati, prima, durante e dopo ciascuna fase del trattamento con farmaco o con placebo. L'analisi statistica dei risultati ha dimostrato la significativa superiorità del Bornaprine rispetto al placebo nel ridurre il tremore (p<0.01) e, in minor misura, alcuni altri sintomi della serie parkinsoniana. Non si sono rilevati effetti collaterali di rilievo, sia dal punto di vista clinico sia da quello strumentale. L'unica eccezione è rappresentata dalla maggiore incidenza di xerostomia nel corso del trattamento con farmaco attivo rispetto a quello con placebo.

     

A controlled double-blind study of tetrabamate versus lorazepam and placebo in generalized anxiety

The anxiolytic efficacy of tetrabamate was evaluated in a multicentric double-blind study versus lorazepam and placebo, in 269 patients with a generalized anxiety disorder according to DSM III-R criteria. The anxiolytic activity of tetrabamate (at 900 mg/day) was significantly superior than that of placebo from day 7 of treatment and equivalent to lorazepam efficacy (at 4.5 mg/day). In the tetrabamate group, 55.3% were considered as "good responders" (as defined by a HARS score reduction equal or superior to 50%), versus 51.3 and 32.9% respectively in the lorazepam and the placebo groups (chi-square = 9.63, p = 0.008). Sheehan's scales (parts 1 and 2), Norris visual analogue scales, CHESS 84, CHESS complement 82 for withdrawal evaluation, physician's overall evaluation of efficacy and tolerance, were also used to assess the clinical effects of tetrabamate. The data on these measures confirmed the anxiolytic efficacy of tetrabamate and showed some advantages in the tetrabamate group in comparison with the lorazepam group: a better global tolerance at the study end point (day 35), a greater efficacy on some anxiety somatic items and lesser frequency and severity of withdrawal symptoms during treatment tapering off.     

Comparison of the effects of zolpidem and triazolam on nocturnal sleep and sleep latency in the morning: a cross-over study in healthy young volunteers

1. Zolpidem (ZPD, 10 mg) was directly compared with triazolam (TRZ, 0.25 mg), a benzodiazepine hypnotic of a short action comparable to ZPD. The compounds were given to healthy young subjects for three nights, in a crossover design. 2. Polysomnographic data of three 150-min sections of the nights as well as the whole nights were analyzed, to clearly detect the proper effects of the very short acting hypnotics, which might be missed in the analysis of whole night. 3. Time courses were significantly different between the two compounds in the ratios (%) of stage wake (SW), stage 2 (S2), slow wave sleep (SWS) and stage REM (SR). 4. Compared to the baseline, SWS was increased by ZPD on the first night, not by TRZ. The separate analysis of the three 150-min sections revealed an increase of SWS during the first 150-min of the ZPD night, suggesting a proper action of ZPD to augment SWS. An increase of S2 and a decrease of SR were caused by TRZ, not by ZPD. However, the separate analysis indicated that ZPD might reduce SR during the first 150-min, which was cancelled by a subsequent rebound increase in the whole night analysis. 5. During the withdrawal period, TRZ, not ZPD, increased SW and SR with worsening of mood in the morning. ZPD did not affect sleep latency in the morning, while TRZ caused a trend of the reduction.     

Topiramate in migraine prophylaxis: a randomised double-blind versus placebo study

Abstract The objectives of this paper are to evaluate the efficacy and tolerability of topiramate, given at the dose of 100 mg/day, in the prophylactic treatment of migraine. The hypothesis that migraine is the result of a condition of neuronal hyperexcitability and the quest for drugs that are able to limit the number of crises justifies the attempt to utilise the new antiepileptic drugs in the prophylaxis of this pathology, which is so important due to its high prevalence and due to the high disability it causes. The study was randomised double-blind versus placebo, lasting 16 weeks, and was preceded by a run-in period of 4 weeks. One hundred and fifteen patients were randomly allocated to treatment with topiramate (TPM) or placebo: 35 patients completed the study in the TPM group and 37 patients in the placebo group. At the end of the double-blind phase of study, in the TPM group, we recorded a significant reduction in the frequency of migraine crises (from 5.26 at baseline to 2.60 in the last 4 weeks), a significant reduction in the quantity of symptomatic drugs taken as compared to the placebo control group (from 6.17±1.80 SD to 2.57±0.80) and a significant downward trend in the number of days of disability over the 16-week period of therapy. In the TPM group, side effects were transient and well tolerated. TPM has thus proven its efficacy and tolerability in the prophylaxis of migraine.     

Randomized double-blind parallel-group study comparing cognitive effects of a low-dose lamotrigine with valproate and placebo in healthy volunteers

PURPOSE: This study aimed at investigating the cognitive and mood effects of lamotrigine (LTG) versus valproate (VPA) and placebo (PBO). METHODS: By studying the effects in healthy volunteers, it is possible to separate the genuine effects of LTG from the cognitive improvements, caused by better seizure control. The study used a pretest-posttest comparison of 50 mg LTG, 900 mg VPA, or PBO in a double-blind single-dummy parallel-group design with 30 healthy volunteers. Study duration was 12 days (with a last control on day 13). Outcome measures included cognitive tests (FePsy neuropsychological test battery), mood scales (ASL; mood-rating scale), and a scale for subjective complaints (ABNAS Neurotoxicity scale). Total sleep time was controlled with actigraphic recordings. The results were analyzed by comparing the change over time (pretest with posttest) for the three treatments with Student's t tests. RESULTS: COGNITIVE TESTS: significant differences between the treatments were found for measurements of cognitive activation (i.e., three of the four simple reaction-time measurements showed statistically significant differences in change between PBO and LTG in favor of LTG (p=0.03; 0.03; 0.04); two of four tests showed statistically significant differences in change between LTG and VPA, both in favor of LTG (p=0.03; 0.05). SUBJECTIVE COMPLAINTS: the ABNAS-neurotoxicity scale reveals a significant reduction of drug-related cognitive complaints for the subjects taking LTG, relative to VPA (p=0.02). MOOD RATING: significant changes were found on the scale assessing "tiredness," showing increased tiredness/sedation for VPA relative to PBO (p=0.02) and on the "timid scale" for LTG reporting "being more at ease" compared with both PBO and VPA (p=0.02; 0.02). The general direction of change for the mood scales was toward "activation" for LTG (five of six scales improved), whereas for VPA, the reverse effect was found (four of six scales showed a change in the direction of "tiredness/sedation"). CONCLUSIONS: Short-term treatment in normal volunteers with a low dose of LTG resulted in improved cognitive activation on simple reaction-time measurements, a more positive subjective report about the impact of drug treatment relative to VPA, and mood changes concurring with the activating effect demonstrated by the cognitive tests.     

Activity and acceptability of indalpine in a double-blind study versus placebo

In this double-bind randomized study involving 35 depressed female inpatients, Indalpine proved significantly superior to placebo on all the criteria used: Hamilton scales for depression and anxiety, clinician's vectorial ratings. Its rapid onset of action was further confirmed by the rapid appearance of significance relative to placebo: as early as the third day of treatment, that is, during the optimum placebo effect period. The results are all more valuable if one considers the magnitude of the placebo effect obtained with daily infusions of isotonic sodium chloride-dextros solution, the possible adjunction of a benzodiazepine and the availability of placebo tablets as an adjunct to the infusions upon request. Acceptabilité was found to be good, especially at the cardiovascular and cholinergic levels.     

Vitamin B6 versus mianserin and placebo in acute neuroleptic-induced akathisia: a randomized, double-blind, controlled study

Treatment strategies against acute neuroleptic-induced akathisia (NIA) include anticholinergic (antimuscarinic) agents, dopamine agonists, GABAergic agents, beta-blockers, benzodiazepines, and serotonin antagonists. However, many patients who have acute akathisia fail to respond. In previous studies, mianserin and vitamin B6 were found to be effective in the treatment of acute akathisia. The purpose of this study was to compare the efficacy of B(6), mianserin and placebo in the treatment of acute NIA. Sixty schizophrenia and schizoaffective inpatients who have NIA were randomly divided to receive vitamin B(6) 1,200 mg/d, mianserin 15 mg/d, or placebo for 5 days, in a double-blind design. The Barnes Akathisia Rating Scale, Brief Psychiatric Rating Scale, and Clinical Global Impression were used to assess the severity of NIA and psychotic symptoms. The assessment was made at baseline and daily for the duration of the study. Compared with the placebo group, the vitamin B(6)-treated and mianserin-treated patients showed a significant improvement in the subjective (P < 0.0001), subjective distress (P < 0.0001), and global (P < 0.0001) subscales. The objective subscale did not show significant positive results (P = 0.056), but there was a trend toward symptom amelioration in both groups. A reduction of at least 2 points on the Barnes Akathisia Rating Scale global subscale was noted in the vitamin B(6) group (13/23, 56%) as well as in the mianserin groups (13/20, 65%), and in only one patient in the placebo group (1/17, 6%; P < 0.0005). Our results indicate that high doses of B(6) and a low dose of mianserin may be a useful addition to current treatments of NIA. The efficacy of vitamin B(6) and mianserin suggests that the pathophysiology of acute NIA is heterogeneous with the various subtypes of acute NIA responding differently to the various pharmacological approaches.     

The treatment of accessory symptoms in narcolepsy: a double-blind cross-over study of a selective serotonin re-uptake inhibitor (femoxetine) versus placebo

A randomized, double-blind cross-over trial was carried out in 10 patients with narcolepsy to evaluate the effect of 600 mg femoxetine versus placebo. In comparison to placebo, femoxetine treatment resulted in a significant decrease in both the number and severity score of cataplectic attacks per day. There were also significantly fewer attacks of sleep paralysis, whilst the effects on nightmare and hypnogenic hallucinations were minor. The frequency of sleep attacks decreased slightly during femoxetine treatment, but the overall estimated sleep time during the day and excessive daytime sleepiness remained un-affected. An ambulatory sleep recording for 48 h one week after the start of the femoxetine and placebo period showed that femoxetine treatment resulted in a significant decrease in the total time spent in REM sleep. The side-effects of femoxetine were restricted to transient nausea in 2 patients. It is concluded that femoxetine or other selective serotonin reuptake inhibitors may be a useful alternative for narcoleptic patients who experience troublesome side-effects with tricyclic antidepressants.     

Psychological effects of (S)-ketamine and N,N-dimethyltryptamine (DMT): a double-blind, cross-over study in healthy volunteers

INTRODUCTION: Pharmacological challenges with hallucinogens are used as models for psychosis in experimental research. The state induced by glutamate antagonists such as phencyclidine (PCP) is often considered as a more appropriate model of psychosis than the state induced by serotonergic hallucinogens such as lysergic acid diethylamide (LSD), psilocybin and N,N-dimethyltryptamine (DMT). However, so far, the psychological profiles of the two types of hallucinogenic drugs have never been studied directly in an experimental within-subject design. METHODS: Fifteen healthy volunteers were included in a double-blind, cross-over study with two doses of the serotonin 5-HT2A agonist DMT and the glutamate N-methyl-D-aspartate (NMDA) antagonist (S)-ketamine. RESULTS: Data are reported for nine subjects who completed both experimental days with both doses of the two drugs. The intensity of global psychological effects was similar for DMT and (S)-ketamine. However, phenomena resembling positive symptoms of schizophrenia, particularly positive formal thought disorder and inappropriate affect, were stronger after DMT. Phenomena resembling negative symptoms of schizophrenia, attention deficits, body perception disturbances and catatonia-like motor phenomena were stronger after (S)-ketamine. DISCUSSION: The present study suggests that the NMDA antagonist model of psychosis is not overall superior to the serotonin 5-HT2A agonist model. Rather, the two classes of drugs tend to model different aspects or types of schizophrenia. The NMDA antagonist state may be an appropriate model for psychoses with prominent negative and possibly also catatonic features, while the 5-HT2A agonist state may be a better model for psychoses of the paranoid type.     

Naltrexone and dysphoria: a double-blind placebo controlled trial

Naltrexone hydrochloride reportedly produces frequent dysphoria. This has led to speculation regarding the role of endorphins in the etiology of depression. Thirty-six subjects completed an 8-week trial of naltrexone or placebo with frequent mood assessments. No significant differences on POMS scales were noted for either subject group. One subject was discontinued from the study because of a severe dysphoric reaction. Naltrexone does not appear to significantly alter mood over a 2-month time course in nonaddicted, healthy individuals. Subpopulations of patients under physiological or psychological stress may react to naltrexone with dysphoric symptoms.     

DL-phenylalanine versus imipramine: a double-blind controlled study.

In a double-blind study, DL-phenylalanine (150--200 mg/24 h) or imipramine (150--200 mg/24 h) was administered to 40 depressed patients (20 patients in each group) for 30 days. Diagnoses were established according to the International Classification of Disease (ICD). The AMP system, the Hamilton Depression Scale and the Bf-S self rating questionnaire (von Zerssen et al., 1974) were used to document psychopathological, neurologic, and somatic changes. Twenty-seven patients (14 on imipramine, 13 on phenylalanine) completed the 30-day trial. No statistical difference could be found between these two drug treatment groups (Student's t-test) using the Hamilton Depression Scale and the Bf-S self rating questionnaire. Ratings for anxiety were significantly lower in the imipramine group on days 10 and 20, but not on day 30; in addition, sleep disturbances were more influenced by imipramine on days 1, 5, and 10, but not on days 20 and 30. Separate analysis of psychopathological syndromes as somatic depressive syndrome and retarded depressive syndrome did not show a group difference (0.05 level of significance using a two-way analysis of variance). It is concluded that DL-phenylalanine might have substantial antidepresant properties. However, certain methodological considerations still warrant a careful interpretation.     

Rotigotine transdermal patch in early Parkinson's disease: a randomized, double-blind, controlled study versus placebo and ropinirole.

Rotigotine is a new, non-ergot dopamine agonist formulated in a transdermal delivery system. The present study was to investigate the efficacy and safety of the rotigotine transdermal patch in the treatment of early Parkinson's disease. Patients (n = 561) were randomized to rotigotine, ropinirole, or placebo. The titration period was up to 13 weeks, and there was a minimum dose-maintenance period of 24 weeks for ropinirole and 33 weeks for rotigotine. The primary endpoint was the proportion of patients with a minimum of 20% decrease in the combined Unified Parkinson's Disease Rating Scale Part II and Part III scores. The responder rate in the rotigotine group was significantly higher than in the placebo group (52% vs. 30%, P < 0.0001). Transdermal rotigotine at doses < or =8 mg/24 h did not show noninferiority to ropinirole at doses < or =24 mg/day. In a post-hoc subgroup analysis, rotigotine < or =8 mg/24 hours had a similar efficacy to ropinirole at doses < or =12 mg/day. The rotigotine transdermal patch was well tolerated. The most common adverse events were application-site reactions, nausea, and somnolence. Application-site reactions were predominantly mild or moderate in intensity. In conclusion, the rotigotine transdermal patch represents an effective and safe option for the treatment of patients with early Parkinson's disease.     

Antidepressant drugs in anergic schizophrenia. A double-blind cross-over study with maprotiline and placebo

Seventeen out of 20 inactive and emotionally withdrawn schizophrenic patients under long-term neuroleptic treatment completed a double-blind cross-over investigation of the possible activating effect of maprotiline, a relatively specific noradrenaline-reuptake inhibitor, compared with that of placebo. Each treatment phase lasted 8 weeks. No significant differences with respect to either the level of activity or schizophrenic symptoms were found between maprotiline (mean dose 138 mg/day) and placebo. Maprotiline provoked a slight psychotic exacerbation in one patient and sedation in another, four patients developed orthostatic hypotension, and two patients had an epileptic seizure. In the light of this and other studies, it must be concluded that antidepressant drugs do not represent any therapeutic advance in the treatment of inactive schizophrenic patients receiving neuroleptics.     

Cerebrovascular reactivity following administration of mirtazapine in healthy probands--a randomized, placebo controlled double-blind clinical study

INTRODUCTION: Cerebrovascular reactivity (CVR) reflects the compensatory dilatory capacity of cerebral arterioles to a dilatory stimulus and is important for maintaining constant cerebral blood flow. A reduced CVR increases the risk of stroke. We recently found that CVR was reduced in patients with depression. This might contribute to the higher risk of stroke that has been found in subjects suffering from depression. The characterization of pathophysiological conditions in the cerebral circulation requires the knowledge of influencing factors on CVR. We therefore investigated the influence that antidepressant administration might have on CVR in humans. METHODS: We investigated CVR in 48 healthy men before and after a 10-day application of either mirtazapine or placebo. CVR was determined by calculating the increase in cerebral blood flow velocity after stimulation with acetazolamide. Blood flow velocities were measured by transcranial Doppler ultrasound. RESULTS: There was no significant group-difference of CVR after the treatment trial compared to baseline. DISCUSSION: Mirtazapine does not seem to have an influence on CVR, or any impact on CVR might have been quickly limited by a cerebral autoregulatory response.     

Intramuscular diclofenac in the acute treatment of migraine: a double-blind placebo controlled study

The aim of this study is to assess, in a double blind fashion, the effect of diclofenac on the pain and associated symptoms in patients with acute migraine. 60 patients with migraine with aura and 60 patients with migraine without aura were assigned at random to receiving intramuscular diclofenac, 75 mg associated to intravenous physiological saline, 10 ml, or physiological saline alone. We used 3 parameters of analgesic evaluation and an analogical scale to asses associated symptoms. We also observed the recurrence and rescue medication percentiles. Patients receiving diclofenac showed a statistically significant improvement of pain 60 minutes after the administration in two of the three parameters(migraine without aura) and in all parameters (migraine with aura). They did not present difference, compared to placebo, on the intensity of associated symptoms. We observed a reduction on the recurrence and rescue medication utilization. Despite being an option to treat migraines attacks in the emergency room settings, diclofenac has a slow onset action and no effects on the associated symptoms.     

Fluoxetine versus placebo: a double-blind study with bulimic inpatients undergoing intensive psychotherapy

In a double-blind trial 40 patients with bulimia nervosa according to DSM III-R criteria were randomly assigned either to a 60 mg fluoxetine group or to a placebo control group. Fluoxetine or placebo was given over a period of 35 days. Parallel to the drug trial, patients participated in an intensive inpatient behavioral psychotherapy program. There were no dropouts at all in the study. Fluoxetine was well tolerated and had only minor adverse effects. In self-ratings and expert ratings concerning attitudes towards eating, eating behavior, and general psychopathology, significant improvements over time were observed in both groups. Using analysis of variance (ANOVA), however, there were no statistically significant "group by time" differences. Results show that the intensive inpatient-care and psychotherapy program was highly effective in changing eating behavior and attitudes as well as general psychopathology. Fluoxetine showed a significant reduction in body weight, especially during the first three weeks of fluoxetine treatment. It was not possible to demonstrate a statistically significant improvement in eating attitudes, eating behavior, and general psychopathology beyond that elicited by intensive inpatient psychotherapy and general inpatient care. These results can possibly be explained by the existence of a "ceiling effect".     

dl-Phenylalanine versus imipramine: A double-blind controlled study

Summary In a double-blind study,dl-phenylalanine (150–200mg/24h) or imipramine (150–200mg/24h) was administered to 40 depressed patients (20 patients in each group) for 30 days.Diagnoses were established according to the International Classification of Diseases (ICD). The AMP system, the Hamilton Depression Scale and the Bf-S self rating questionnaire (von Zerssen et al., 1974) were used to document psychopathological, neurologic, and somatic changes.Twenty-seven patients (14 on imipramine, 13 on phenylalanine) completed the 30-day trial. No statistical difference could be found between these two drug treatment groups (Student'st-test) using the Hamilton Depression Scale and the Bf-S self rating questionnaire. Ratings for anxiety were significantly lower in the imipramine group on days 10 and 20, but not on day 30; in addition, sleep disturbances were more influenced by imipramine on days 1, 5, and 10, but not on days 20 and 30.Separate analysis of psychopathological syndromes as somatic depressive syndrome and retarded depressive syndrome did not show a group difference (0.05 level of significance using a two-way analysis of variance).It is concluded thatdl-phenylalanine might have substantial antidepressant properties. However, certain methodological considerations still warrant a careful interpretation.     

Verapamil in the prophylaxis of episodic cluster headache: a double-blind study versus placebo

The authors performed a double-blind, double-dummy study to compare the efficacy of verapamil with placebo in the prophylaxis of episodic cluster headache. After 5 days' run-in, 15 patients received verapamil (120 mg tid) and 15 received placebo (tid) for 14 days. The authors found a significant reduction in attack frequency and abortive agents consumption in the verapamil group. Side effects were mild. These findings provide objective evidence for the effectiveness of verapamil in episodic cluster headache prophylaxis.