Eperisone

Eperisone (formulated as the eperisone hydrochloride salt) is an antispasmodic drug. Eperisone (formulated as the eperisone hydrochloride salt) is an antispasmodic drug. Eperisone acts by relaxing both skeletal muscles and vascular smooth muscles, and demonstrates a variety of effects such as reduction of myotonia, improvement of circulation, and suppression of the pain reflex. The drug inhibits the vicious circle of myotonia by decreasing pain, ischaemia, and hypertonia in skeletal muscles, thus alleviating stiffness and spasticity, and facilitating muscle movement Eperisone also improves dizziness and tinnitus associated with cerebrovascular disorders or cervical spondylosis. Eperisone has a relatively low incidence of sedation when compared with other antispasmodic drugs; this simplifies the clinical application of the drug and makes it an attractive choice for patients who require antispasmodic therapy without a reduction in alertness. Eperisone also facilitates voluntary movement of the upper and lower extremities without reducing muscle power; it is therefore useful during the initial stage of rehabilitation and as a supporting drug during subsequent rehabilitative therapy. Eperisone hydrochloride is available as the brand name preparations Myonal and Epry as 50 mg sugar-coated tablets, or as 10% granules for oral administration. An experimental form of the drug, as a transdermal patch system, has shown promising results in laboratory tests on rodents; however, this product is not currently available for human use. In adults, the usual dose of eperisone is 50–150 mg per day, in divided doses, after meals. However, the dosage is adjusted by the prescribing clinician depending on factors such as severity of symptoms, patient age and response. Eperisone has not been established as definitely safe for paediatric use, therefore its use in paediatrics cannot be recommended without further study. If elderly patients are treated with eperisone, a reduced dose is recommended, and the patient should be closely monitored for signs of psychological hypofunction during treatment.