Hello, and thank you for writing to JustAnswer with your question.
From your description, it sounds possible that he has a disc compressing a nerve or another similar problem in the back. This kind of condition can cause similar symptoms as you are describing in the legs and feet.
Of course stress will increase the tension in the muscles as well, and the cigarettes cause restriction of the capillaries, decreasing circulation to the muscles as well as the extremities. Keeping weight under control is important to prevent excess physical stress and gravity from effecting the back even further.
It is great to hear he is trying to quit smoking, and perhaps this information will help motivate him along a little further with this process.
Besides the stress reduction and continuing to cut back on the smoking, he should have a thorough physical examination and investigative imaging (x-rays, possibly cat scan) of his back.
Hopefully there is nothing so bad as to require surgery. Certain physicians are quicker to do surgery on the back than others, so a second opinion is a good idea, if the first opinion seems excessive. Sometimes injections are tried and can be very helpful. Always, once one is over the acute period of pain, learning and performing stretching and strengthening exercises for the muscles in the back is helpful. These should be recommended by the examining physician or a referred physical therapist.
Non-steroidal anti-inflammatories (NSAIDs) are usually prescribed for this type of problem. They work to decrease inflammation as well as pain. They should be taken with food (the pain medication propoxyphen that he is taking is a combination synthetic opioid and acetaminophen, and does not have anti-inflammatory effects). It is always a good idea to speak with his physician before starting even an over the counter medication if there is any concern.
In the short term he could try a heating pad two to three times per day for aproximately 20 minutes (never go to sleep with a heating pad). This helps to bring in extra circulation and healing to the area. It is also important to drink plenty of water, up to 10 cups per day, as in some cases the hydration can help with the disc spaces, especially if the individual is slightly hydrated.
Plenty of rest is key to recovery, as well as proper alignment when sleeping, sitting, moving and lifting.
This web site explains the importance of stress reduction and contains several types of stress reduction exercises to try. Likely he will need demonstration to help him learn some of these techniques: http://helpguide.org/mental/stress_signs.htm
This is a link to the Mayo Clinic web site regarding back pain. It is a very useful medical website as it discusses causes, diagnosis, treatment, alternative treatments and each subject is labeled and on a separate page, making it easy to go to the area of information you are in most need of: