Medications for back pain?

Try other things 1st: Best for back pain is prevention. Once back pain starts, use of proper body mechanics, losing weight, regular exercise, correct posture, ergonomical work site should be adopted. Try heat and/or ice. Maybe massage. Medication does not correct an anatomic spinal problem. If you must take meds, start with nsaids such as Ibuprofen or naproxen. If you need anything stronger, see your doctor.

Different Mechanisms: Back pain can be due to multiple causes and knowing the cause will help your physician choose proper medications. Medications to treat pain are generally categorized as narcotics, anti-inflammatories, membrane stabilizers as well as oral versus topical prepations. For mild new onset back pain due to strain and sprain anti-inflammatories are usually a good start if there are no contraindications.

Best medication: There is no "best" medication. The one that works the best for you is the best.