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1.
Clin Exp Pharmacol Physiol ; 36(5-6): 469-77, 2009 May.
Article in English | MEDLINE | ID: mdl-19673928

ABSTRACT

1. The main objective of the present study was to compare the bioavailability/bioequivalence of a new prolonged-release (PR) formulation of torasemide with an immediate-release (IR) formulation. In addition, we assessed the pharmacokinetics of both formulations, as well as the urine pharmacodynamics. 2. Two doses (5 and 10 mg) of PR torasemide were compared with the same doses of IR torasemide in a single-blind, single-dose, two-treatment, two-period, cross-over, sequence-randomized clinical trial in 20 healthy volunteers (two groups; n = 10 in each group). Torasemide plasma concentrations were measured by high-pressure liquid chromatography-electrospray ionization mass spectrometry. Torasemide urine concentrations, the diuretic effect of torasemide, urine electrolytes and urine density were also determined. 3. Plasma bioequivalence parameters, based on logged values, were as follows: (i) in the 5 mg group, the area under the plasma drug concentration-time curve from t = 0 to last measurable drug concentration at time t (AUC(0-t)) tablet ratio was 1.03 (90% confidence interval (CI) 0.91-1.17) and C(max) was 0.82 (90% CI: 0.68-0.98); and (ii) in the 10 mg group, the AUC(0-t) was 1.07 (90% CI 0.99-1.14) and C(max) was 0.68 (90% CI 0.60-0.78). The PR formulation showed a significantly prolonged t(max) compared with the IR formulation. The amount of torasemide recovered in the urine 24 h after administration was higher with the PR formulation for both doses. The natriuretic rate versus torasemide excretion rate for the PR and IR formulations were successfully regressed to a sigmoid E(max) model. Pharmacodynamic urine evaluations were similar with both formulations, although urine volume and urine electrolyte excretion were lower for the PR formulation in the first hour after administration. However, the PR formulation showed higher natriuretic efficiency. No significant adverse events were reported. 4. In conclusion, both formulations of torasemide showed similar systemic exposure (AUC). However, the PR formulation had a lower rate of absorption (lower C(max) and prolonged t(max)). The PR formulation had urinary excretion rates that were associated with a higher natriuretic efficiency and more constant diuresis.


Subject(s)
Sulfonamides/administration & dosage , Sulfonamides/pharmacokinetics , Administration, Oral , Adult , Biological Availability , Cross-Over Studies , Delayed-Action Preparations , Diuretics/administration & dosage , Diuretics/blood , Diuretics/pharmacokinetics , Diuretics/urine , Dose-Response Relationship, Drug , Humans , Male , Single-Blind Method , Sulfonamides/blood , Sulfonamides/urine , Therapeutic Equivalency , Torsemide , Young Adult
2.
Int J Clin Pharmacol Ther ; 47(12): 726-32, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19954711

ABSTRACT

UNLABELLED: Low-molecular-weight heparins (LMWHs) are antithrombotic drugs that differ on biochemical and pharmacological properties. OBJECTIVE: This study was conducted to compare the pharmacodynamic time-course of two LMWHs, bemiparin and enoxaparin, at high prophylactic doses. METHODS: This was an open, randomized, single-blind, cross-over study to compare the pharmacodynamic time-course, safety and tolerability of two LMWHs, bemiparin 3500 IU and enoxaparin 4000 IU at subcutaneous single doses in 12 healthy male volunteers. Anti-Xa activity (main biomarker of heparin activity), anti-IIa activity, total and free tissue factor pathway inhibitor (TFPI), activated partial thromboplastin time (APTT), thrombin time (TT) and thromboplastin-thrombomodulin mediated time (Tp-TmT) were investigated. RESULTS: Bemiparin 3500 IU achieved more anti-Xa activity than enoxaparin 4000 IU, measured by the area under the curve (geometric mean AUC0t) (bemiparin 3.69 vs. enoxaparin 3.33 IU h/ml; p < 0.001). Maximum anti-Xa activity was reached at 3 hours and there were anti-Xa measurable levels up to 16 h after subcutaneous administration. Anti-Xa activity half-life was 5.44 hours for bemiparin and 4.71 hours for enoxaparin. Anti-IIa activity was above the limit of quantification (0.05 IU/ml) in only 2 volunteers after bemiparin and in 8 after enoxaparin. The "in-vivo" anti-Xa:IIa ratios were: bemiparin 37.9 (95% CI: 28.0 - 55.3, n = 2) and enoxaparin 16.3 (95% CI: 12.2 - 23.4, n = 8). Enoxaparin induced a higher release of total TFPI, but not on free TFPI, and a longer prolongation of APTT and TT (Emax) than bemiparin, with no differences between groups on Tp-TmT. Adverse events (one in each group) were mild and transient. CONCLUSION: Bemiparin 3500 IU showed more anti-Xa activity and higher anti-Xa: anti-IIa relationship than enoxaparin 4000 IU in healthy volunteers. Both treatments were well tolerated.


Subject(s)
Anticoagulants/pharmacology , Blood Coagulation Factors/drug effects , Enoxaparin/pharmacology , Heparin, Low-Molecular-Weight/pharmacology , Adolescent , Adult , Anticoagulants/adverse effects , Anticoagulants/pharmacokinetics , Blood Coagulation Tests , Cross-Over Studies , Enoxaparin/adverse effects , Enoxaparin/pharmacokinetics , Heparin, Low-Molecular-Weight/adverse effects , Heparin, Low-Molecular-Weight/pharmacokinetics , Humans , Male , Time Factors
3.
Neuropsychobiology ; 55(3-4): 203-12, 2007.
Article in English | MEDLINE | ID: mdl-17878744

ABSTRACT

BACKGROUND/AIMS: Benzodiazepines (BZDs) are the most effective of the psychotropic drugs in the treatment of anxiety disorders. Tolerance has been reported for the majority of BZDs after chronic administration. However, little attention has been paid to the possibility that tolerance might be present after the intermittent oral administration of BZDs. The objectives of the present study were to assess tolerance development after the administration of two intermittent single oral doses of alprazolam given 15 days apart in healthy volunteers, and to compare the results obtained using measures from different domains: neurophysiological, psychomotor and subjective. METHODS: Twenty-four healthy volunteers received 2 mg of alprazolam orally on two experimental days, 15 days apart. Plasma concentrations and pharmacodynamics (PD) were assessed before drug intake and at different times in the following 24 h. PD was assessed through EEG (relative alpha and relative beta-1 activities), cancellation task (total and correct number of responses) and visual analogue scales (activity and drowsiness). RESULTS: No differences were observed in the PKs of alprazolam between occasions. A proteresis was present in both administrations for impairments of psychomotor performance and relative beta-1 activity, whereas it was present only after the second administration for subjective assessments and relative alpha activity. The proteresis on the second occasion was higher than on the first one. CONCLUSIONS: The administration of two single oral doses of alprazolam, 2 weeks apart in healthy volunteers, yielded the same PKs on both occasions, but significant changes were observed in the PD profile. Acute tolerance was observed after the second administration. Two patterns of acute tolerance development were obtained: (1) impairments of psychomotor performance and relative beta-1 activity, and (2) subjective assessments and relative alpha activity.


Subject(s)
Alprazolam/administration & dosage , Drug Tolerance/physiology , Electroencephalography/drug effects , Hypnotics and Sedatives/administration & dosage , Psychomotor Performance/drug effects , Adolescent , Adult , Alprazolam/blood , Alprazolam/pharmacokinetics , Area Under Curve , Drug Administration Routes , Evaluation Studies as Topic , Female , Humans , Hypnotics and Sedatives/blood , Hypnotics and Sedatives/pharmacokinetics , Male , Neuropsychological Tests , Pain Measurement/methods , Single-Blind Method , Time Factors
4.
Biol Psychol ; 72(3): 251-6, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16406216

ABSTRACT

Inconsistencies among affective startle reflex modulation studies may be due to differences in the startle potentiation produced by the specific content of the images used, to individual differences in sensitivity to negative stimuli, or to the interaction of both factors. To explore this interaction, 52 undergraduates obtaining extreme scores on a self-report measure of the Behavioral Inhibition System (BIS) participated in an affective startle reflex modulation paradigm. A significant interaction between BIS group (high versus low) and image content emerged from the MANOVA. Comparing startle magnitude between fear and pleasant images, low BIS participants did not seem to show startle potentiation, whereas high BIS participants did. Both groups displayed potentiated startle during blood-disgust images. The present results suggest the importance of considering personality variables and their interaction with image content in the affective startle modulation paradigm.


Subject(s)
Affect , Behavior Therapy/methods , Blood , Fear , Inhibition, Psychological , Phobic Disorders/psychology , Phobic Disorders/therapy , Reflex, Startle , Adult , Female , Humans , Male , Phobic Disorders/diagnosis , Photic Stimulation , Reinforcement, Psychology
5.
Methods Find Exp Clin Pharmacol ; 27(4): 227-34, 2005 May.
Article in English | MEDLINE | ID: mdl-16082423

ABSTRACT

Eberconazole is a topical imidazole derivative, which has shown high potency against dermatophytes and yeasts (several species of Candida, Malassezia) in vitro and in experimental models. Clinical trials have found that the compound has a high degree of efficacy against dermatophytes and good tolerability. Evaluation of its a) topical and general tolerability, b) eventual development of sensitisation, c) local availability, and d) degree of systemic absorption. Two clinical trials with 28 healthy young volunteers of both sexes were performed. In Study I, placebo or eberconazole cream (2%) were applied at increasing doses: day 1 (0.5 g), days 2-3 (1 g), days 4-5 (2 g), days 6-7 (4 g), days 8-9 (8 g), and days 10-11 (12 g). On day 1, each application area was washed with ethanol-soaked gauzes at different times to assess availability of the active compound. In Study II, eberconazole cream (1%) was applied on day 1 and again at least one week later. After the first application, blood and urine samples were obtained at different times to assess systemic absorption. The only change observed was slight redness in a few volunteers after both active and placebo applications. This remitted spontaneously without intervention and we were able to continue with the administration of repeated increasing-doses. A few participants described side effects; these were all of mild intensity, and occurred in areas where placebo or eberconazole were applied, mainly within the first hour postapplication. The most frequent effect after the first application was coldness, and after repeated increasing-doses there was itching. No signs or symptoms of skin reactivity were observed following reexposure to the product. No clinically relevant changes were observed in vital signs (systolic and diastolic blood pressure, heart rate, body temperature), ECG, or analytical parameters (clinical haematology and biochemistry). The quantity of compound collected through washing gauzes decreased progressively over time. Plasma and urine concentrations of eberconazole were below the quantification limit of the analytical method (5 ng/ml) at all times. Eberconazole cream is a topical antimycotic drug that has good local and general tolerability. It has acceptable topical availability, no detectable systemic drug levels, and does not appear to cause skin sensitivity.


Subject(s)
Antifungal Agents/pharmacology , Antifungal Agents/pharmacokinetics , Cycloheptanes/pharmacology , Cycloheptanes/pharmacokinetics , Imidazoles/pharmacology , Imidazoles/pharmacokinetics , Administration, Topical , Adult , Antifungal Agents/adverse effects , Biological Availability , Cycloheptanes/adverse effects , Drug Hypersensitivity/etiology , Female , Humans , Imidazoles/adverse effects , Male , Skin Absorption
6.
Neuroscience ; 103(3): 581-92, 2001.
Article in English | MEDLINE | ID: mdl-11274780

ABSTRACT

Analyses of scalp-recorded sleep spindles have demonstrated topographically distinct slow and fast spindle waves. In the present paper, the electrical activity in the brain corresponding to different types of sleep spindles was estimated by means of low-resolution electromagnetic tomography. In its new implementation, this method is based on realistic head geometry and solution space is restricted to the cortical gray matter and hippocampus. In multichannel all-night electroencephalographic recordings, 10-20 artifact-free 1.25-s epochs with frontally, parietally and approximately equally distributed spindles were marked visually in 10 normal healthy subjects aged 20-35years. As a control condition, artifact-free non-spindle epochs 1-3s before or after the corresponding spindle episodes were marked. Low-resolution electromagnetic tomography demonstrated, independent of the scalp distribution, a distributed spindle source in the prefrontal cortex (Brodmann areas 9 and 10), oscillating with a frequency below 13Hz, and in the precuneus (Brodmann area 7), oscillating with a frequency above 13Hz. In extremely rare cases only the prefrontal or the parietal source was active. Brodmann areas 9 and 10 have principal connections to the dorsomedial thalamic nucleus; Brodmann area 7 is connected to the lateroposterior, laterodorsal and rostral intralaminar centrolateral thalamic nuclei. Thus, the localized cortical brain regions are directly connected with adjacent parts of the dorsal thalamus, where sleep spindles are generated. The results demonstrated simultaneously active cortical spindle sources which differed in frequency by approximately 2Hz and were located in brain regions known to be critically involved in the processing of sensory input, which is in line with the assumed functional role of sleep spindles.


Subject(s)
Frontal Lobe/physiology , Magnetoencephalography , Parietal Lobe/physiology , Sleep/physiology , Adult , Electroencephalography , Female , Humans , Male , Time Factors
7.
Clin Pharmacokinet ; 40(4): 245-62, 2001.
Article in English | MEDLINE | ID: mdl-11368291

ABSTRACT

Dexketoprofen trometamol is a water-soluble salt of the dextrorotatory enantiomer of the nonsteroidal anti-inflammatory drug (NSAID) ketoprofen. Racemic ketoprofen is used as an analgesic and an anti-inflammatory agent, and is one of the most potent in vitro inhibitors of prostaglandin synthesis. This effect is due to the (S)-(+)-enantiomer (dexketoprofen), while the (R)-(-)-enantiomer is devoid of such activity. The racemic ketoprofen exhibits little stereoselectivity in its pharmacokinetics. Relative bioavailability of oral dexketoprofen (12.5 and 25mg, respectively) is similar to that of oral racemic ketoprofen (25 and 50mg, respectively), as measured in all cases by the area under the concentration-time curve values for (S)-(+)-ketoprofen. Dexketoprofen trometamol, given as a tablet, is rapidly absorbed, with a time to maximum plasma concentration (tmax) of between 0.25 and 0.75 hours, whereas the tmax for the (S)-(+)-enantiomer after the racemic drug, administered as tablets or capsules prepared with the free acid, is between 0.5 and 3 hours. The drug does not accumulate significantly when administered as 25mg of free acid 3 times daily. The profile of absorption is changed when dexketoprofen is ingested with food, reducing both the rate of absorption (tmax) and the maximal plasma concentration. Dexketoprofen is strongly bound to plasma proteins, particularly albumin. The disposition of ketoprofen in synovial fluid does not appear to be stereoselective. Dexketoprofen trometamol is not involved in the accumulation of xenobiotics in fat tissues. It is eliminated following extensive biotransformation to inactive glucuroconjugated metabolites. No (R)-(-)-ketoprofen is found in the urine after administration of dexketoprofen, confirming the absence of bioinversion of the (S)-(+)-enantiomer in humans. Conjugates are excreted in urine, and virtually no drug is eliminated unchanged. The analgesic efficacy of the oral pure (S)-(+)-enantiomer is roughly similar to that observed after double dosages of the racemic compound. At doses above 7mg, dexketoprofen was significantly superior to placebo in patients with moderate to severe pain. A dose-response relationship between 12.5 and 25mg could be seen in the time-effects curves, the superiority of the 25mg dose being more a result of an extended duration of action than of an increase in peak analgesic effect. A plateau in the analgesic activity of dexketoprofen trometamol at the 25mg dose is suggested. The time to onset of pain relief appeared to be shorter in patients treated with dexketoprofen trometamol. The drug was well tolerated.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Ketoprofen/pharmacokinetics , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Biotransformation , Humans , Ketoprofen/therapeutic use , Stereoisomerism
8.
Psychopharmacology (Berl) ; 157(4): 358-67, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11605094

ABSTRACT

RATIONALE: The "fear-potentiated startle" paradigm has been extensively used in animal studies, and more recently in human experimental psychopharmacology to evaluate the effects of anxiogenic and anxiety-relieving drugs. Previous human studies have shown that both the baseline and the fear-potentiated responses can be inhibited by anxiety-relieving drugs, suggesting drug activity on two different emotional states, the former reflecting a resting condition and the latter more akin to pathological anxiety. OBJECTIVES: To examine to which extent the reductions induced by a benzodiazepine on the basic and the fear-potentiated startle responses are of equal intensity, and whether or not the drug shows a predominant, i.e., selective, effect on either. METHODS: The effects of three increasing doses of the benzodiazepine alprazolam (0.25, 0.5, and 1.0 mg) were assessed on the human baseline and fear-potentiated startle responses. Twelve healthy volunteers attended the laboratory on four experimental days and received either alprazolam or placebo according to a double-blind crossover balanced design. Startle recordings were undertaken 2 h after drug intake. Fear potentiation was implemented by means of an electric-shock-anticipation experimental procedure. Additionally, subjective self-reports of sedation and anxiety and psychomotor performance were obtained at 2 and 3 h, respectively, after drug administration. RESULTS: Alprazolam dose-dependently impaired psychomotor performance and produced increases in subjective anxiolytic activity and sedation, although the latter did not reach statistical significance. Additionally, the drug reduced the magnitude of the startle response both in the absence and in the presence of a threat-related cue, although a differentially greater inhibitory effect was seen on the fear-potentiated response as the dose increased. CONCLUSIONS: Alprazolam showed a greater inhibitory effect on the fear-potentiated startle than on the baseline reflex, suggesting a more selective action of the drug on those structures mediating potentiation of the behavioral response by anxiety.


Subject(s)
Alprazolam/pharmacology , Anti-Anxiety Agents/pharmacology , Fear/psychology , Reflex, Startle/drug effects , Acoustic Stimulation , Adult , Alprazolam/blood , Anti-Anxiety Agents/blood , Blinking/drug effects , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Male , Psychomotor Performance/drug effects , Reaction Time/drug effects
9.
Psychopharmacology (Berl) ; 143(3): 280-5, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10353431

ABSTRACT

In the present study, we assessed the effects of the potent benzodiazepine alprazolam on the human acoustic startle response in healthy volunteers. Eight undergraduate students received single oral doses of placebo and alprazolam 2 mg on 2 separate days, according to a double-blind balanced crossover design. Electromyographic activity of the orbicularis oculi muscle was recorded 5, 7 and 11 h after drug administration. At each recording time, subjects received 21 acoustic stimuli (1 KHz, 116 dB, 50 ms duration) separated by variable intervals (8-30 s, mean 16.5 s). Consistent with previous results obtained for diazepam in humans, alprazolam significantly reduced the amplitude of the startle reflex. A patent increase in onset latency was also observed, this being a novel effect not previously described for benzodiazepines in human studies. Both effects were maximum at 5 h after dosing, the startle response experiencing a recovery as the drug disappeared from systemic circulation. These results indicate a potent inhibitory effect of alprazolam on baseline startle at the dose used, with a robust time-dependent recovery of initial values effectively counteracting between-session habituation.


Subject(s)
Alprazolam/pharmacology , Anti-Anxiety Agents/pharmacology , Reflex, Startle/drug effects , Adult , Blinking/drug effects , Cross-Over Studies , Double-Blind Method , Female , Humans , Male , Reflex, Startle/physiology
10.
Psychopharmacology (Berl) ; 154(1): 85-95, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11292011

ABSTRACT

RATIONALE: Ayahuasca is a South American psychoactive beverage that contains the naturally occurring psychedelic agent N,N-dimethyltryptamine (DMT). This "tea" has been used for centuries in religious and medicinal contexts in the rain forest areas of South America and is presently gaining the attention of psychedelic users in North America and Europe. OBJECTIVES: In the present study, the psychological effects and tolerability of ayvahuasca were assessed. METHODS: Three increasing doses of encapsulated freeze-dried ayahuasca (0.5, 0.75, and 1.0 mg DMT/kg body weight) were administered to six healthy male volunteers with prior experience in the use of this tea, in a single-blind crossover placebo-controlled clinical trial. RESULTS: Ayahuasca produced significant dose-dependent increases in five of the six subscales of the Hallucinogen Rating Scale, in the LSD, MBG, and A scales of the Addiction Research Center Inventory, and in the "liking", "good effects" and "high" visual analogue scales. Psychological effects were first noted after 30-60 min, peaked between 60-120 min, and were resolved by 240 min. The tea was well tolerated from a cardiovascular point of view, with a trend toward increase for systolic blood pressure. Modified physical sensations and nausea were the most frequently reported somatic-dysphoric effects. The overall experience was regarded as pleasant and satisfactory by five of the six volunteers, while one volunteer experienced an intensely dysphoric reaction with transient disorientation and anxiety at the medium dose and voluntarily withdrew from the study. CONCLUSIONS: Ayahuasca can be described as inducing changes in the perceptual, affective, cognitive, and somatic spheres, with a combination of stimulatory and visual psychoactive effects of longer duration and milder intensity than those previously reported for intravenously administered DMT.


Subject(s)
Hallucinogens/pharmacology , N,N-Dimethyltryptamine/pharmacology , Plants/chemistry , Adult , Hallucinogens/adverse effects , Hemodynamics/drug effects , Humans , Male , N,N-Dimethyltryptamine/adverse effects , Plant Extracts , Single-Blind Method , South America
11.
J Clin Pharmacol ; 38(S1): 33S-40S, 1998 12.
Article in English | MEDLINE | ID: mdl-9882080

ABSTRACT

The pharmacokinetics of dexketoprofen trometamol were evaluated in two studies using healthy volunteers. In the first study, the relative bioavailability of a single oral capsule of dexketoprofen free acid 25 mg or dexketoprofen trometamol 25 mg (given as 37 mg of the trometamol salt) was compared to ketoprofen 50 mg in 18 healthy volunteers. In the second study, the pharmacokinetics and tolerability of oral dexketoprofen trometamol in tablet form were evaluated after either a single 25 mg dose (24 volunteers) or a repeated dose of 25 mg twice daily for 7 days (12 volunteers). The absorption of dexketoprofen from dexketoprofen trometamol capsules was bioequivalent to that of ketoprofen. On the other hand, the extent of absorption of dexketoprofen free acid was significantly lower than that for ketoprofen. Dexketoprofen trometamol showed the most rapid absorption rate, with highest Cmax and shortest t(max) values, whereas dexketoprofen free acid had the slowest absorption rate, and ketoprofen had an intermediate absorption rate. After repeated-dose administration of dexketoprofen trometamol, the pharmacokinetic parameters were similar to those obtained after single doses, indicating that no drug accumulation occurred. Dexketoprofen trometamol was well tolerated, with no clinically relevant adverse events reported.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Ketoprofen/analogs & derivatives , Tromethamine/analogs & derivatives , Absorption , Administration, Oral , Adult , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Biological Availability , Cross-Over Studies , Double-Blind Method , Female , Humans , Ketoprofen/pharmacology , Ketoprofen/toxicity , Male , Sex Factors , Tromethamine/pharmacology , Tromethamine/toxicity
12.
J Clin Pharmacol ; 38(S1): 41S-45S, 1998 12.
Article in English | MEDLINE | ID: mdl-9882081

ABSTRACT

This randomized three-way, crossover pharmacokinetic study was performed to determine whether food or an antacid alters the bioavailability of dexketoprofen trometamol. A total of 24 healthy volunteers received three single 25 mg doses of dexketoprofen trometamol administered either in fasting condition, after an antacid (Maalox), or after a high-fat breakfast. Each volunteer received the three treatments in a randomized order, with a 7-day washout period between treatments. Blood samples were taken at regular intervals up to 24 h after dose. Plasma dexketoprofen concentrotions were determined by HPLC and the main outcome measures were area under curve of concentration vs. time (AUC0-infinity), maximal plasma concentration (Cmax), and time to reach maximal concentration (t(max)). Administration of an antacid 10 min before dexketoprofen trometamol had no clinically relevant effect on any of the pharmacokinetic parameters. Food did not alter the extent of absorption of dexketoprofen trometamol, but t(max) was significantly increased and C(max). significantly decreased compared with the fasting state. In conclusion, we can state that neither antacid nor food has a significant effect on the overall bioavailability of dexketoprofen trometamol.


Subject(s)
Antacids/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Food-Drug Interactions , Ketoprofen/analogs & derivatives , Tromethamine/analogs & derivatives , Adolescent , Adult , Anti-Inflammatory Agents, Non-Steroidal/blood , Biological Availability , Cross-Over Studies , Drug Interactions , Female , Humans , Ketoprofen/pharmacology , Ketoprofen/toxicity , Male , Middle Aged , Tablets , Tromethamine/pharmacology , Tromethamine/toxicity
13.
Drug Alcohol Depend ; 62(3): 215-23, 2001 May 01.
Article in English | MEDLINE | ID: mdl-11295326

ABSTRACT

Reliability and convergent-discriminant validity of a Spanish version of the Hallucinogen Rating Scale (HRS) were assessed in two differentiated populations of hallucinogen users involving the retrospective assessment of drug effects. In Study 1 (immediate assessment), 75 European users of the South American hallucinogenic drink ayahuasca answered the HRS 4 h after drug intake in their habitual setting. In Study 2 (delayed assessment), 56 adult polydrug users answered the HRS and a short form of the Addiction Research Center Inventory (ARCI) recalling the effects they experienced when they last took a hallucinogen, in order to test the convergent-discriminant validity of HRS with the scales of the standard questionnaire used in most studies involving psychoactive drugs. The HRS scales showed increases after both the immediate and delayed retrospective assessment of drug effects. Reliability data indicated that four of the six scales show an acceptable level of internal consistency. Significant but limited correlations were found between the Perception and Somaesthesia scales and the ARCI LSD scale, pointing out the questionnaire's construct validity. Thus, the HRS was sensitive to hallucinogenic drug effects other than those elicited by intravenous N,N-dimethyltryptamine (DMT), for which it was originally designed, and showed reasonable reliability and convergent validity. Results suggest its usefulness in the evaluation of subjective effects elicited by psychoactive drugs with hallucinogenic properties, and constitute a preliminary approach to the effects of ayahuasca in European subjects.


Subject(s)
Hallucinogens , Surveys and Questionnaires , Adolescent , Adult , Female , Humans , Male , Middle Aged , Psychometrics , Retrospective Studies
14.
Psychiatry Res ; 45(2): 79-93, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1488471

ABSTRACT

Mapping of the electroencephalogram (EEG) has been found to be a valuable method in clinical neuropsychopharmacology. It is evident that careful treatment of artifacts is of utmost importance for EEG data processing, as artifacts that contaminate the EEG data can lead to spurious results. The artifact-processing method described in this article splits signal analysis into a preprocessing step, yielding individual electro-oculographic (EOG) regression factors for EOG minimization, and into a processing step, yielding target variables. The combination of avoiding, minimizing, and identifying artifacts, as well as visual checking of face validity, will help remove artifactual effects from the EEG.


Subject(s)
Artifacts , Brain Mapping , Brain/drug effects , Heme/therapeutic use , Memory Disorders/drug therapy , Aged , Electroencephalography , Electrooculography , Equipment Design , Female , Heme/administration & dosage , Humans , Male , Middle Aged , Neuropharmacology
15.
Cochrane Database Syst Rev ; (3): CD003387, 2003.
Article in English | MEDLINE | ID: mdl-12917964

ABSTRACT

BACKGROUND: Transcranial magnetic stimulation (TMS) was introduced as a neurophysiological technique in 1985 when Anthony Barker and his team developed a compact machine that permitted non-invasive stimulation of the cerebral cortex (Barker 1985). Since its introduction, TMS has been used to evaluate the motor system, to study the function of several cerebral regions, and for the pathophysiology of several neuropsychiatric illnesses. In addition, it has been suggested that TMS might have therapeutic potential. Some controlled studies have evaluated the effects of repetitive TMS (rTMS) in patients with obsessive-compulsive disorder (OCD). Greenberg (Greenberg 1997) observed that a single session of right prefrontal cortex stimulation produced a significant decrease in compulsive urges in OCD patients lasting over eight hours. Other studies have reported transitory improvements in mood but there are no observations for changes in anxiety or obsessions. OBJECTIVES: To develop a systematic review on the clinical efficacy and safety of transcranial magnetic stimulation from randomised controlled trials in the treatment of obsessive-compulsive disorder. SEARCH STRATEGY: An electronic search was performed including the Cochrane Collaboration Depression, Anxiety and Neurosis Review Group trials register (last searched June, 2002), the Cochrane Controlled Trials Register (Issue 2, 2002), MEDLINE (1966-2002), EMBASE (1974-2002), PsycLIT (1980-2002), and bibliographies from reviewed articles. SELECTION CRITERIA: Randomised controlled trials assessing the therapeutic efficacy and safety of transcranial magnetic stimulation for obsessive-compulsive disorder. DATA COLLECTION AND ANALYSIS: All reviewers independently extracted the information and verified it by cross-checking. Disagreements were resolved through discussion. MAIN RESULTS: Three trials were included in the review and only two contained data in a suitable form for quantitative analysis. It was not possible to pool any results for a meta-analysis. No difference was seen between rTMS and sham TMS using the Yale-Brown Obsessive-Compulsive Scale or the Hamilton Depression Rating Scale for all time periods analysed. REVIEWER'S CONCLUSIONS: There are currently insufficient data from randomised controlled trials to draw any conclusions about the efficacy of transcranial magnetic stimulation in the treatment of obsessive-compulsive disorder.


Subject(s)
Obsessive-Compulsive Disorder/therapy , Physical Stimulation/methods , Transcranial Magnetic Stimulation/therapeutic use , Humans , Randomized Controlled Trials as Topic
16.
Cochrane Database Syst Rev ; (2): CD003493, 2002.
Article in English | MEDLINE | ID: mdl-12076483

ABSTRACT

BACKGROUND: Transcranial magnetic stimulation can either excite or inhibit cortical areas of the brain, depending on whether the speed of the repetitive stimulation is applied at high or low frequencies. It has been used for physiological studies and it has also been proposed as a treatment for depression. OBJECTIVES: To assess the clinical efficacy and safety of transcranial magnetic stimulation for treating depression. SEARCH STRATEGY: An electronic search was performed including the Cochrane Collaboration Depression, Neurosis and Anxiety Review Group trials register (last searched June, 2001), the Cochrane Controlled Trials Register (Issue 2, 2001), MEDLINE (1966-2001), EMBASE (1974-2001), PsycLIT (1980-2001), and bibliographies from reviewed articles. Unpublished data and grey literature were searched through personal communications with researchers. SELECTION CRITERIA: Randomised controlled trials assessing the therapeutic efficacy and safety of transcranial magnetic stimulation for depression. DATA COLLECTION AND ANALYSIS: All reviewers independently extracted the information and verified it by cross-checking. Disagreements were resolved through discussion. Continuous data: When similar studies were grouped, the overall standardised mean difference was calculated under a fixed effect model weighted by the inverse variance method with 95% confidence intervals. (In the presence of statistical heterogeneity, a random effects model was to be used.) MAIN RESULTS: Sixteen trials were included in the review and fourteen contained data in a suitable form for quantitative analysis. Most comparisons did not show differences between rTMS and other interventions. No difference was seen between rTMS and sham TMS using the Beck Depression Inventory or the Hamilton Depression Rating Scale, except for one time period (after two weeks of treatment) for left dorsolateral prefrontal cortex and high frequency; and also for right dorsolateral prefrontal cortex and low frequency, both in favour of rTMS and both using the Hamilton scale. Comparison of rTMS (left dorsolateral prefrontal cortex and high frequency) with electroconvulsive therapy showed no difference except for psychotic patients after two weeks treatment, using the Hamilton scale, which indicated that electroconvulsive therapy was more effective than rTMS. REVIEWER'S CONCLUSIONS: The information in this review suggests that there is no strong evidence for benefit from using transcranial magnetic stimulation to treat depression, although the small sample sizes do not exclude the possibility of benefit.


Subject(s)
Depression/therapy , Transcranial Magnetic Stimulation/therapeutic use , Humans , Physical Stimulation/methods
17.
Int J Clin Pharmacol Ther ; 33(7): 397-400, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7582396

ABSTRACT

The aim of this study was to investigate the gender-related pharmacokinetic differences after a single oral dose of diltiazem (120 mg) in 12 healthy subjects (6 males and 6 females). Kinetic parameters were calculated from serum concentrations obtained by means of a specific HPLC method. The total area under the concentration-time curve (AUC0-infinity) was 917.03 +/- 342.13 ng.h-1/ml for females and 1,192.97 +/- 329.93 ng.h-1/ml for males. Peak serum levels (Cmax) were 181.29 +/- 48.03 ng/ml and 194.29 +/- 93.81 for females and males, respectively. The time to reach maximum concentration (Tmax) was 2.2 +/- 0.8 h for both. The biological elimination t1/2 was 4.58 +/- 2.08 h and 5.59 +/- 2.44 h, showing an elimination rate (kel) of 0.174 +/- 0.062 h-1 and 0.149 +/- 0.075 h-1, and a mean residence time (MRT) of 8.56 +/- 1.94 h and 8.88 +/- 2.78 h for females and males, respectively. Male subjects showed higher values than females, but no significant difference was observed when comparing pharmacokinetic parameters by gender. Diltiazem was well tolerated by all subjects.


Subject(s)
Calcium Channel Blockers/pharmacokinetics , Diltiazem/pharmacokinetics , Adult , Biological Availability , Calcium Channel Blockers/blood , Chromatography, High Pressure Liquid , Diltiazem/blood , Female , Half-Life , Humans , Male , Sex Characteristics
18.
J Pharm Pharmacol ; 56(4): 471-6, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15099442

ABSTRACT

The pharmacokinetics/tolerability of lanreotide Autogel have been evaluated. Healthy volunteers (n = 24) first received immediate-release lanreotide as a single subcutaneous (s.c.) injection. After two days, 40 or 60 mg lanreotide Autogel was injected subcutaneously. Blood was sampled at various intervals for 56 days. Systemic/local adverse events and changes in biological profile/vital signs were recorded. Lanreotide Autogel produced a prolonged-release pharmacokinetic profile: mean area under the serum concentration-time curve from time 0 to infinity (AUC) was 53.73 +/- 8.99 and 79.48 +/- 13.06 ng mL(-1) day for 40 and 60 mg, respectively, mean peak serum concentration (C(max)) was 4.38 +/- 2.91 and 5.71 +/- 3.52 ng mL(-1), respectively, median time to reach C (minimum-maximum) was 0.50 (0.083-18.0) and 0.38 (0.083-9.01) days, respectively, mean apparent elimination half-life was 21.63 +/- 9.42 and 22.01 +/- 9.87 days, respectively, and relative bioavailability was 0.93 +/- 0.12 and 0.82 +/- 0.15, respectively. Thus, lanreotide Autogel exhibited linear pharmacokinetics for the doses studied. Pharmacokinetic profiles were similar in both genders, apart from statistically significant differences in C(max) and C(max)/AUC. The Autogel formulation of lanreotide was well tolerated, with systemic adverse events being mild/moderate. Erythema and a painless subcutaneous induration were the most common local adverse events. Lanreotide Autogel provided a prolonged dosing interval and good tolerability for treating acromegaly and carcinoid syndrome.


Subject(s)
Antineoplastic Agents/pharmacokinetics , Peptides, Cyclic/pharmacokinetics , Somatostatin/pharmacokinetics , Adolescent , Adult , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Area Under Curve , Delayed-Action Preparations , Female , Half-Life , Humans , Injections, Subcutaneous , Male , Metabolic Clearance Rate , Peptides, Cyclic/administration & dosage , Peptides, Cyclic/adverse effects , Somatostatin/administration & dosage , Somatostatin/adverse effects , Somatostatin/analogs & derivatives
19.
Int J Clin Pharmacol Res ; 9(3): 183-95, 1989.
Article in English | MEDLINE | ID: mdl-2568348

ABSTRACT

Modafinil (CRL 40476) is a recently developed central alpha adrenergic agonist with vigilance-promoting properties. In a double-blind, placebo-controlled sleep laboratory study, its single-dose effects on objectively and subjectively evaluated sleep, morning awakening, and early morning behaviour were investigated and compared with amphetamine. Ten young healthy volunteers of both sexes spent 12 nights in the sleep laboratory: one adaptation night, one baseline night, five drug nights (100 mg and 200 mg modafinil; 10 mg and 20 mg d-amphetamine; placebo) and five subsequent washout nights. The drugs were administered in one week intervals according to a Latin square design. Somnopolygraphic investigations were performed between 22h30 and 06h00. Subjects received the drug orally half an hour before bedtime. A self-rating scale for sleep and awakening quality and early morning behavior was completed subsequent to the morning toilet. Thereafter, noopsychic and thymopsychic variables were evaluated utilizing a psychometric test-battery. Statistical analyses of objective sleep variables demonstrated that modafinil causes no significant changes as compared to a placebo. Sleep initiation remained unchanged after all of the drugs, while sleep maintenance was impaired dose-dependently after d-amphetamine. Thus, total sleep time and sleep efficiency decreased significantly after 20 mg d-amphetamine as compared to the placebo and modafinil. In regard to sleep architecture a reduction of sleep stage 2 and rapid eye movement-sleep occurred under d-amphetamine while modafinil did not exhibit such an effect. Subjective sleep quality was significantly better after modafinil than after the reference compound. Subjective awakening quality and well-being in the morning did not show any significant findings. Furthermore, no differences were observed between the placebo and the other drugs concerning objective awakening quality (evaluated by psychometric tests). Critical flicker frequency increased significantly after 20 mg d-amphetamine as compared to the placebo. Pulse rate and evening and morning blood pressure remained unchanged. These data stress the necessity to differentiate between "vigility-increasing" properties of amphetamine and "vigilance-promoting" properties of modafinil.


Subject(s)
Behavior/drug effects , Benzhydryl Compounds/pharmacology , Central Nervous System Stimulants/pharmacology , Dextroamphetamine/pharmacology , Sleep/drug effects , Adult , Double-Blind Method , Electroencephalography , Electromyography , Electrooculography , Female , Flicker Fusion/drug effects , Humans , Male , Modafinil , Sleep Stages/drug effects
20.
Methods Find Exp Clin Pharmacol ; 24 Suppl D: 129-37, 2002.
Article in English | MEDLINE | ID: mdl-12575480

ABSTRACT

Pharmacokinetic/pharmacodynamic modeling, together with electroencephalography (EEG), have been successfully applied to obtain in vivo pharmacological information of different drugs acting on the central nervous system (CNS) in humans and of the systems with which the drugs interact. Almost all types of variables used to assess the activity of drugs in the human CNS have already been applied in pharmacokinetic/pharmacodynamic research. However, compared with more traditional approaches to quantify the pharmacodynamics of neuropsychotropic drugs, the EEG method has the advantage of being objective, sensitive, continuous and reproducible. The present review focuses mostly on benzodiazepine pharmacology. A selection of some basic aspects that can be covered using pharmaco-EEG and pharmacokinetic/pharmacodynamic modeling from in vivo studies performed in humans in pharmacological research will be introduced: i) determination of the pharmacological characteristics of a compound; ii) comparison of potencies among drugs; iii) comparison of efficacy among drugs; iv) tolerance development; v) metabolite role; vi) enantiomers; vii) drug-drug interactions; viii) circadian rhythms; ix) factors affecting the observed effect; and x) the gain of physiopathological information about the systems with which drugs interact. Looking at the quantity and quality of the results obtained for the benzodiazepines, pharmacokinetic/pharmacodynamic modeling using EEG measures appears to be an ideal tool, and is potentially useful for other drugs acting on the CNS.


Subject(s)
Benzodiazepines/pharmacokinetics , Electroencephalography/drug effects , Models, Biological , Benzodiazepines/pharmacology , Central Nervous System/drug effects , Central Nervous System/physiology , Circadian Rhythm/drug effects , Circadian Rhythm/physiology , Drug Tolerance/physiology , Electroencephalography/methods , Humans
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