Need to find the exact cause and treat accordingly. The treatment depends upon the cause and the stage at which it is diagnosed and is decided upon by the treating doctor.

Muscle spasm has many reasons . Like habit, posture , PIVD, trauma and infection etc. there is insufficient information regarding muscle spasm . Any muscle relaxant like tolperisone, thiocholchicoside, or eperisone etc along with pain killer can do better but you will get best result with Physiotherapy and exercise once pain subsides.

You can take a good muscle relaxant, as well as use gel and hot fomentation