Muscle relaxers relieve back pain by relaxing and depressing the central nervous system to eliminate pain or the sharp feeling present with severe muscle spasms, explains WebMD. Muscle relaxers work to stabilize muscle tension in the lower back to improve mobility and minimize pain from chronic or acute back problems.
The use of muscle relaxants for back pain is often short-term because the drugs can become addicting, according to WebMD. In addition, muscle relaxers may cause side effects, especially when taken on an empty stomach. Potential side effects include dry mouth, urinary retention, drowsiness or dizziness, and possible dependence or addiction. Older adults, pregnant women and individuals with a history of depression, drug or alcohol addiction should not take muscle relaxants.
Physicians recommend taking muscle relaxers for back pain prior to sleeping in the evening to ensure a restful sleep and to minimize any nausea that can occur from the drug, according to WebMD. People who take a muscle relaxant should not operate machinery or drive while under the influence of the drug because it may cause excess drowsiness or sleepiness.
Alternative treatments for back pain include low doses of antidepressants, exercise and physical therapy, injections of anti-inflammatory medications or in extreme cases back surgery, according to the Mayo Clinic.