An overview of treatment resistant depression.
Living with depression is difficult as it is, but treatment resistant depression can leave you feeling desperate and hopeless.
Introduction
If you were diagnosed with major depressive disorder and haven’t seen an improvement in your symptoms with treatment, it’s possible that you have treatment resistant depression. Although it might feel like it sometimes-- you absolutely aren’t alone. It’s estimated that as many as 30% of adults with depression do not respond to antidepressant medication treatment.
What is treatment resistant depression?
While there isn’t a single, universally agreed-upon definition of treatment resistant depression, a patient is generally thought to have it if they haven’t responded to at least two different antidepressant medications-- assuming that both medications were taken at their respective recommended doses and the patient continued taking each medication for a minimum of six weeks.
The biology of depression itself remains somewhat of a mystery to psychiatric researchers.
What causes treatment resistant depression?
The challenge in pinpointing the root cause of treatment resistant depression can generally be blamed on the fact that even in 2019, the biology of depression itself remains somewhat of a mystery to psychiatric researchers. Depression is thought to be influenced by a variety of physiological factors, although researchers have yet to agree on what all of these factors are. There is one thing that researchers tend to agree on though, and it involves the activity of certain neurotransmitters in the brain. Serotonin, norepinephrine, and dopamine are thought to play a critical role in regulating emotion and mood, and an imbalance in these chemicals can lead to chronic depression symptoms. This neurotransmitter theory is what drives the medication-based approach to depression treatment, with the most commonly prescribed antidepressants being SSRIs (selective serotonin reuptake inhibitors). SSRI medications primarily affect levels of serotonin in the brain, but they tend to have little effect on other neurotransmitters. Subsequently, patients that suffer depression symptoms correlated with an imbalance of dopamine and/or norepinephrine find little to no relief from this class of medication. These neurotransmitters can be targeted with other classifications of antidepressant drugs such as MAOIs, tricyclics, and SNRIs-- however, these medications are known to trigger harsh side effects that are less likely to be tolerated by the patient. This may explain why some patients are unable to find success with medication-based treatment.
Solutions
If medication hasn’t worked for you, there is still hope. Transcranial magnetic stimulation is a treatment for major depressive disorder that targets the area of your brain responsible for regulating emotion and mood with stimulation generated from an electromagnetic coil. This stimulation increases the overall activity of neurotransmitters in the brain, including those that aren’t affected by SSRIs. This makes TMS a promising solution for patients with treatment resistant depression. TMS is also an excellent option for individuals that want to avoid the side effects associated with antidepressant medication or are unable to take such medications due to other health issues. TMS is FDA approved, which means that it is covered under Medicare and most major health insurance providers.