My jaw hurts often... how can i cure it? what medicine i have to take?

Depends: It depends why your jaw hurts.. It it from bruxism, from a broken tooth, from an infection, or from a cavity? Each requires different treatment, not just medicine. That's why you need to call a local dentist for an appointment.

See your dentist!: There can be many causes. You could be clenching or grinding your teeth; your occlusion or bite could be off, it could be an organic problem in the temporo-mandibular joint itself. You could have had trauma to your jaw at some point in your life in the past that you have forgotten about. Sometime heat or cold can help but... You should see your dentist for a thorough exam and diagnosis.