I've been treated for depression with prescription drugs and counseling for about 16 years. I have been on so many medications and combinations of medications that it's hard to remember them all. But it seems that none of them have been any help, so I am refusing to take any more meds. Are there people with depression who just don't respond to medication? Could I be one of them? If that is indeed the case, is there anything else I can do to deal with the day-to-day fight?

— Sophie, Idaho

Unfortunately, 20 to 30 percent of people who receive several courses of therapy with the currently available antidepressant medications do not get adequate relief from their depression.

Although the term treatment-resistant depression is used to describe this phenomenon, this type of depression is not really a single condition, and there are a lot of reasons antidepressants may not work, including undetected medical conditions (such as thyroid disease) or an unrecognized psychiatric condition (such as substance abuse or post-traumatic stress disorder). Sometimes it’s simply a matter of finding the right medication.

Although you seem to be firm in your resolve not to take other antidepressants, it’s not clear to me to what extent you and your doctor have explored other factors that might get in the way of an antidepressant response for you. If you haven't had such a discussion, you should have a careful evaluation, which might also include a consultation with a new doctor who can provide a second opinion.

With respect to other things that you can do, people who exercise regularly, receive the extra social support that comes with spending time with people who care about them, and are able to reduce life stress by getting practical help to solve nagging problems are less likely to get stuck in depressive episodes. Because you also mention counseling among the treatments that have not helped, you might also consider a change in the type of counseling you seek, or try going online to check out some of the Web sites that offer self-help programs in positive psychology or cognitive behavior therapy.