I'm not a medical profesional, but have extensive experience with lower back pain. Here's what my chiropractor instructs me to do, however, readers would be well advised to consult their own physicians. With that said...

The two most common lower back ailments are strained muscles and sciatica. Depending on severity, either condition can be fairly debilitating. As far as home treatment, both respond fairly well to some simple measures.

My treatment includes ice pack therapy and an OTC anti-inflamatory (aspirin or ibuprofen). For sciatica I get relief by laying on the floor with my legs draped over the edge of a bed, sofa or chair. This helps take pressure off those painful pinched nerves. Heat therapy is not advisable for sciatica because the warmth will only cause the swelling in those damaged nerves to become worse.

Muscle strains can be eased initially with cold therapy at the onset, followed a day or two later with warmth (hot compresses, bath, heating pad). Muscle preparations (BenGay, Flexall, etc.) can also be beneficial, but never use them in conjunction with an external heat source as you can literally cook your flesh!