How to treat muscle spasms?
The quickest and simplest way to relieve muscle spasms is to apply warm compression, massage, and stretch out the muscles. Certain bigger neck muscles like the trapezius are easier to stretch then the deeper ones (like rhomboids) that may need a professional physiotherapist.
Medication
Medications like muscle relaxants, NSAIDs will also provide some relief.
When to see a doctor?
Important to note that if these neck spasms are associated with shooting sensations down the arms, it might be a nerve root irritation due to a slipped disc in the neck. In these situations, it's best to see your family doctor.