Why do people with severe depression often complain about having tremendous pain in many areas of their body, specifically head, stomach, esophagus and chest and what causes constipation if they're still eating, but in smaller amounts?
Pain and depression often are intertwined—and in several different ways. Pain from physical causes such as nerve compression, metastatic cancer, etc., can be extremely stressful and debilitating, and can worsen depression.
On the other hand, depression itself often leads to worsened pain. In the midst of major depression, people are more aware of physical symptoms, and may tend to be preoccupied with physical symptoms that might not normally be of great concern—-such as headaches, backaches or muscle aches.
In other situations, depression and physical pain may be manifestations of the same condition—-in fibromyalgia, there is both inflammation and tenderness of muscles and depressed mood. Some studies suggest that increased activity in pain centers of the brain may lead to both muscle pain and depression in fibromyalgia.
Finally, there are some conditions which seem to increase the risk of each other—-people with migraine headaches are more likely to get depressed, and people with depression are more likely to develop migraine headaches.
Depression can have different manifestations. Some people experience depression through emotional symptoms such as low mood, tearfulness and sadness. Others experience it primarily through cognitive symptoms, such as difficulty concentrating or completing tasks. Still others experience depression mostly through their bodies, with troubling physical symptoms, feeling “sick” or weak, and with worries about their health.
Depression is one of the most common reasons for people visiting their internists, or for missing work, and physical symptoms such as back pain, headaches, muscle aches, etc. are among the most common complaints in those settings.
Interestingly, a number of psychiatric medications are useful for treatment of pain related to depression. Older antidepressants such as amitriptyline have been used for a long time in low doses for their analgesic properties. More recently, serotonin reuptake inhibitors (such as fluoxetine or sertraline) and serotonin-norepinephrine reuptake inhibitors (such as venlafaxine or duloxetine) have been used for their pain-relieving properties, in conditions such as diabetic neuropathy.
Other medicines such as gabapentin, an anticonvulsant, are also useful in treating pain.
To answer the second question (about constipation in depression), this may reflect several issues, including decreased physical activity, decreased water intake, changed diet, and possibly depression-related changes in the activity of the bowel. Successful treatment of depression generally leads to improvement of depression-related pain symptoms.
Finally, when depression and physical pain coexist, it is important not to assume that the pain is “caused by” depression. A medical evaluation is essential in order to evaluate other possible illnesses that could cause these symptoms.