Generic medicines are just as effective as brand medicines. The difference in rates are due to the fact that patent has been purchased and money is not paid for the research process, Zanaflex Generic (Tizanidine) is used to manage muscle spasms. The issues can include pain, muscle tightness, or stiffness. Zanaflex Generic (Tizanidine) belongs to a class of drugs called alpha-2-adrenergic agonists. Since these types of drugs works on the similar way, so they are often used to treat similar conditions like spasm of muscles.