Medications for cervical dystonia are used to treat muscle spasms in the neck. They work by blocking nerve signals to the muscles, which helps to reduce muscle contractions and spasms. Medication examples include onabotulinumtoxinA (Botox), abobotulinumtoxinA (Dysport), and incobotulinumtoxinA (Xeomin), are typically given as injections.