Prophylactic tolperisone for post-exercise muscle soreness causes reduced isometric force--a double-blind randomized crossover control study

Effects of CYP2C19 genetic polymorphism on the pharmacokinetics of tolperisone in healthy subjects

Tolperisone hydrochloride is a centrally-acting muscle relaxant used for relieving spasticities of neurological origin and muscle spasms associated with painful locomotor diseases. It is metabolized to the inactive metabolite mainly by CYP2D6 and, to a lesser extent, by CYP2C19 and CYP1A2. In our previous study, the pharmacokinetics of tolperisone was significantly affected by the genetic polymorphism of CYP2D6, but the wide interindividual variation of tolperisone pharmacokinetics was not explained by genetic polymorphism of CYP2D6 alone. Thus, we studied the effects of CYP2C19 genetic polymorphism on tolperisone pharmacokinetics. Eighty-one subjects with different CYP2C19 genotypes received a single oral dose of 150 mg tolperisone with 240 mL of water, and blood samples were collected up to 12 h after dosing. The plasma concentration of tolperisone was measured by a liquid chromatography-tandem mass spectrometry system. The CYP2C19PM group had significantly higher C_max and lower CL/F values than the CYP2C19EM and CYP2C19IM groups. The AUC_inf of the CYP2C19PM group was 2.86-fold and 3.00-fold higher than the CYP2C19EM and CYP2C19IM groups, respectively. In conclusion, the genetic polymorphism of CYP2C19 significantly affected tolperisone pharmacokinetics.

The comparative study of clinical efficacy and safety of baclofen vs tolperisone in spasticity caused by spinal cord injury

In the present study we compared the clinical efficacy and safety of baclofen vs tolperisone in spasticity caused by spinal cord injury. A total of 150 patients were enrolled in the present study and were divided into two groups with 75 patients in each group, receiving baclofen or tolperisone, respectively. We used Modified Ashworth Scale, Medical research council scale, Barthel Index, and Coefficient of efficacy to measure clinical efficacy. After 6-week treatment, both groups demonstrated significant improvement in muscle tone, muscle strength and functional outcome (Group I, 1.55 ± 0.053, 2.79 ± 0.032, 59.31 ± 1.32; Group II, 1.57 ± 0.053, 3.04 ± 0.032, 73 ± 1.32 respectively). There was no significant difference regarding improvement in muscle tone and muscle strength between the two groups (Group I, 1.055 ± 0.053 vs Group II, 1.57 ± 0.053; Group I, 2.79 ± 0.032 vs Group II, 3.04 ± 0.032, p > 0.05). However, the improvement in functional outcomes was greater in group II as compared to that in group I (Group I, 59.31 ± 1.32 vs Group II, 73 ± 1.32, p < 0.05). In addition, overall efficacy coefficient was greater for group II as compared to group I (Group I, 3.6 vs Group II, 2.3, p < 0.05). Group I had more side effects compared to Group II. Compared to baclofen, tolperisone offers greater improvement in activities of daily living compared to baclofen.

Comparative study of therapeutic response to baclofen vs tolperisone in spasticity

BACKGROUND

Spasticity from the upper motor neuron syndrome can result from a variety of conditions affecting the cortex or spinal cord. Some of the more common conditions associated with spasticity include spinal cord injury, cerebral palsy, and post-stroke syndrome. In this study we compared the efficacy and safety of baclofen vs tolperisone in spasticity. One hundred fifty patients with cerebral palsy or post stroke or spinal cord injury associated spasticity were enrolled in present study. Group I comprised of Seventy-five patients receiving baclofen and group II comprised of 75 patients receiving tolperisone. For efficacy measurement 4 evaluation methods were used, 1) Modified Ashworth Scale for muscle tone, 2) Medical research council scale for muscle strength and 3) Barthel Index for functional outcome 4) Coefficient of efficacy. In efficacy evaluation, both groups showed significant improvement in muscle tone, muscle strength and functional outcome at week 6 (Group I, 1.55±0.053, 2.79+0.032, 59.31±1.32; Group II, 1.57±0.053, 3.04±0.032, 73±1.32 respectively). In between the group analysis, there was no significant difference in muscle tone improvement in both the groups after 6 weeks (Group I, 1.055±0.053 vs Group II, 1.57±0.053, p>0.05). Group II showed non-significant but greater improvement in muscle strength (Week 6; Group I, 2.79±0.032 vs Group II, 3.04±0.032, p>0.07). Improvement in functional outcomes was greater in group II as compared to group I (Group I, 59.31±1.32 vs Group II, 73±1.32, p<0.05). Overall efficacy coefficient was greater for group II (3.6) as compared to group I (2.3). Baclofen showed more side effects compared to tolperisone in, asthenia being the most frequent. Tolperisone offers greater improvement in activities of daily living compared to baclofen. Tolperisone is more tolerable drug as compared to baclofen.

Basic aspects of the pharmacodynamics of tolperisone, a widely applicable centrally acting muscle relaxant

Tolperisone (2-methyl-1-(4-methylphenyl)-3-piperidin-1-ylpropan-1-one hydro-chloride) was introduced in the clinical practice more than forty years ago and is still evaluated as a widely applicable compound in pathologically elevated skeletal muscle tone (spasticity) and related pains of different origin. In the present review, basic pharmacodynamic effects measured on whole animals, analyses of its actions on cell and tissue preparations and molecular mechanism of action on sodium and calcium channels are summarized as recently significantly new data were reported.

Clinical pharmacology of analgesics assessed with human experimental pain models: bridging basic and clinical research

The medical impact of pain is such that much effort is being applied to develop novel analgesic drugs directed towards new targets and to investigate the analgesic efficacy of known drugs. Ongoing research requires cost-saving tools to translate basic science knowledge into clinically effective analgesic compounds. In this review we have re-examined the prediction of clinical analgesia by human experimental pain models as a basis for model selection in phase I studies. The overall prediction of analgesic efficacy or failure of a drug correlated well between experimental and clinical settings. However, correct model selection requires more detailed information about which model predicts a particular clinical pain condition. We hypothesized that if an analgesic drug was effective in an experimental pain model and also a specific clinical pain condition, then that model might be predictive for that particular condition and should be selected for development as an analgesic for that condition. The validity of the prediction increases with an increase in the numbers of analgesic drug classes for which this agreement was shown. From available evidence, only five clinical pain conditions were correctly predicted by seven different pain models for at least three different drugs. Most of these models combine a sensitization method. The analysis also identified several models with low impact with respect to their clinical translation. Thus, the presently identified agreements and non-agreements between analgesic effects on experimental and on clinical pain may serve as a solid basis to identify complex sets of human pain models that bridge basic science with clinical pain research.

Clinical comparative study: efficacy and tolerability of tolperisone and thiocolchicoside in acute low back pain and spinal muscle spasticity

Study Design

We performed a multicentric, randomized, comparative clinical trial. Eligible patients were randomly assigned to receive 150 mg of Tolperisone thrice daily or 8 mg of Thiocolchicoside twice daily for 7 days.

Purpose

To assess the efficacy and tolerability of Tolperisone in comparison with Thiocolchicoside in the treatment of acute low back pain with spasm of spinal muscles.

Overview of Literature

No head on clinical trial of Tolperisone with Thiocolchicoside is available and so this study is done.

Methods

The assessment of muscle spasm was made by measuring the finger-to-floor distance (FFD), articular excursion in degrees on performing Lasegue's maneuver and modified Schober's test. Assessment of pain on movement and spontaneous pain (pain at rest) of the lumbar spine was made with the help of visual analogue scale score.

Results

The improvement in articular excursion on Lasegue's maneuver was significantly greater on day 3 (p = 0.017) and day 7 (p = 0.0001) with Tolperisone as compared to Thiocolchicoside. The reduction in FFD score was greater on day 7 (p = 0.0001) with Tolperisone. However there was no significant difference in improvement in Schober's test score on day 3 (p = 0.664) and day 7 (p = 0.192). The improvement in pain score at rest and on movement was significantly greater with Tolperisone (^p = 0.0001).

Conclusions

Tolperisone is an effective and well tolerated option for treatment of patients with skeletal muscle spasm associated with pain.

NMR analysis, protonation equilibria and decomposition kinetics of tolperisone

The rate constants of spontaneous and hydroxide-catalyzed decomposition and the tautomer-specific protonation constants of tolperisone, a classical muscle relaxant were determined. A solution NMR method without any separation techniques was elaborated to quantitate the progress of decomposition. All the rate and equilibrium constants were determined at four different temperatures and the activation parameters were calculated. The molecular mechanism of decomposition is proposed.

Tolperisone: a typical representative of a class of centrally acting muscle relaxants with less sedative side effects

Tolperisone, a piperidine derivative, is assigned to the group of centrally acting muscle relaxants and has been in clinical use now for decades. The review summarizes the known pharmacokinetics, pharmacodynamics, toxicology and side effects in humans and the clinical use of tolperisone. A future perspective for further exploration of this drug is given.

HPLC determination of tolperisone in human plasma

A simple high performance liquid chromatographic (HPLC) method was developed for the determination of tolperisone in human plasma. Tolperisone and internal standard (chlorphenesin) were isolated from 1 mL of plasma using 8 mL of dichlormethane. The organic phase was collected and evaporated under nitrogen gas. The residue was then reconstituted with 300 mL aliquot of mobile phase and a 100 mL aliquot was injected onto the C18 reverse-phased column. The mobile phase, 45% methanol containing 1% glacial acetic acid and 0.05% 1-hexanesulfonic acid was run at a flow rate of 1 mL/min. The column effluent was monitored using UV detector at 260 nm. The retention times for tolperisone and the internal standard were approximately 7.1 and 8.4 min, respectively. The standard curve was linear with minimal intra-day and inter-day variability. The quantification limit of tolperisone in human plasma was 10 ng/ mL. The proposed method has been applied to the determination of pharmacokinetic profile of tolperisone in Koreans. The Tmax of tolperisone in Koreans (0.94 +/- 0.42 h) was not significantly differ from that reported in Europeans (0.5-1 h), but the mean half-life in Koreans (1.14 +/- 0.27 h) was shorter than that in Europeans (2.56 +/- 0.2 h). The proposed HPLC method is simple, accurate, reproducible and suitable for pharmacokinetic study of tolperisone.

A comparative study of the action of tolperisone on seven different voltage dependent sodium channel isoforms

The specific, acute interaction of tolperisone, an agent used as a muscle relaxant and for the treatment of chronic pain conditions, with the Na(v1.2), Na(v1.3), Na(v1.4), Na(v1.5), Na(v1.6), Na(v1.7), and Na(v1.8) isoforms of voltage dependent sodium channels was investigated and compared to that of lidocaine. Voltage dependent sodium channels were expressed in the Xenopus laevis oocyte expression system and sodium currents were recorded with the two electrode voltage clamp technique. Cumulative dose response relations revealed marked differences in IC(50) values between the two drugs on identical isoforms, as well as between isoforms. A detailed kinetic analysis uncovered that tolperisone as well as lidocaine exhibited their blocking action not only via state dependent association/dissociation with voltage dependent sodium channels, but a considerable fraction of inhibition is tonic, i.e. permanent and basic in nature. Voltage dependent activation was affected to a minor extent only. A shift in steady-state inactivation to more negative potentials could be observed for most drug/isoform combinations. The contribution of this shift to overall block was, however, small at drug concentrations resulting in considerable overall block. Recovery from inactivation was affected notably by both drugs. Lidocaine application led to a pronounced prolongation of the time constant of the fast recovery process for the Na(v1.3), Na(v1.5), and Na(v1.7) isoforms, indicating common structural properties in the local anesthetic receptor site of these three proteins. Interestingly, this characteristic drug action was not observed for tolperisone.