How long does the pain normally last for people suffering from tennis elbow/tendonitis?

Usually months: Pain typically lasts several months to some degree, and depends upon severity as well as activity requirements of the patient. Rest is an essential component of treatment, and the more active someone is, the more stubborn this condition tends to be. Surgery is not typically offered until someone has had 6 months of active conservative treatment.

Varies: Some people respond to treatment in a few days to a few weeks, others months. Some do well with therapy, stretching, icing, activity reduction. Others need a cortisone injection, others require surgery.