Your concern is very admirable. Many people whose driving is impaired by pain, alcohol, depression, or dementia are unable to even ask this important question.
There are some studies that point to an increased risk of car accident for people who have chronic low back pain. Similar studies are needed to assess the effect of pain on people from other conditions such as chronic headache, neck pain, or nerve conditions.
Scientists who study driving behavior say that chronic pain may have similar effects on memory and attention as alcohol. A group of adults with chronic pain studied in the Netherlands had the same driving impairments as someone with an 0.80 percent blood alcohol level. An alcohol level this high is linked with three times the number of car accidents.
Chronic pain patients have a worse driving performance compared to normal, healthy adults. Older adults (65 years old and older) in pain seem to have a higher accident rate, too. Women in this group have the highest rate of motor vehicle accidents.
The statistics may not be enough to tell you to get off the road but your own concern is enough to follow-up with some testing. Talk to your doctor or the highway patrol about their recommendations.
D. S. Veldhuijzen, et al. Effect of Chronic Nonmalignant Pain on Highway Driving Performance. In Pain. May 2006. Vol. 122. No. 1-2. Pp. 28-35.'