Shingles (herpes zoster) is an acute infection of the nerves that supply sensation to the skin, generally at one or several spinal levels and on one side of the body (right or left). Patients with shingles usually have had chickenpox earlier in life. The herpes virus that causes chickenpox is believed to exist in a dormant state within the spinal nerve roots long after the chickenpox resolves. In people with shingles, this virus reactivates to cause infection along the sensory nerve, leading to nerve pain and usually an outbreak of shingles (tiny blisters on the same side of the body and at the same nerve level). The back pain in patients with shingles of the lumbar area can precede the skin rash by days. Successive crops of tiny blisters can appear for several days and clear with crusty inflammation in one to two weeks. Patients occasionally are left with a more chronic nerve pain (postherpetic neuralgia). Treatment can involve symptomatic relief with lotions, such as calamine, or medications, such as acyclovir (Zovirax), for the infection and pregabalin (Lyrica) or lidocaine (Lidoderm) patches for the pain.
If low back pain gets worse or does not improve after two to three days of home treatment, contact a primary-care physician. The physician can evaluate the patient and perform a neurological exam in the office to determine which nerve root is being irritated, as well as rule out other serious medical conditions. If there are clear signs that the nerve root is being compressed, a physician can prescribe medications to relieve the pain, swelling and irritation; he or she also may recommend limitation of activities. If these treatment options do not provide relief within two weeks, it may be time to consider other diagnostic studies and possibly surgery.