Other people you know may have recovered from their depression more easily: A few months of therapy or antidepressants, and they were back to normal. But it hasn't been like that for you, no matter what you've tried.
There's no one reason for treatment-resistant depression. For most people, it's probably a mix of different factors. Some of them are beyond your control, such as the genes you were born with. Some things you can control.
Keep working with your doctor to find the right combination of treatments that will help you feel better.
Medication Problems
Not staying on a medicine long enough.Antidepressants can take as long as 6 to 8 weeks before they fully take effect. Unfortunately, many people -- and sometimes even doctors -- give up on a drug too early, before it's had a chance to help.
Skipping doses. You'll never know if a drug is working unless you take it exactly as prescribed.
Unpleasant side effects. Many people who have side effects stop taking their antidepressants. That isn't a good idea. Instead, talk to your doctor. You might be able to get rid of or ease the side effects, or switch to a different drug or combo of drugs. Also, keep in mind that many side effects tend to decrease over time.
Drug interactions. Some other medications don't mix well with antidepressants. When taken at the same time, neither one may work normally. In some cases, interactions could be dangerous.
The wrong medicine or the wrong dose. Antidepressant drugs work differently in different people. Unfortunately, there's no way to predict how well a depression medicine will work without trying it. So finding the right medicine, at the right dose, takes some degree of trial and error -- and occasionally, some time. Many people give up before they find the right one.
Your DNA
Researchers have begun to look at genes that may be linked with harder-to-treat forms of depression in some people. But genetic tests can't, as yet, pinpoint which medicines are the most effective for a given person.
Your Health
Some medical conditions -- like heart disease, cancer, or thyroid problems -- can contribute to depression. Other conditions, like anorexia, can too. It's important that you get appropriate treatment for any other health issues as well as your depression.
Substance abuse often goes hand-in-hand with depression. It can trigger it or make it worse, and it can interfere with the effects of antidepressant medicines. If you have a substance abuse problem, you need to get help.
The Wrong Diagnosis
It's unfortunate, but it happens. Some people are simply misdiagnosed. You might actually have another condition, like bipolar disorder, an anxiety disorder, or a substance-induced mood disorder, and not treatment-resistant depression.
That's why it's so important to work with an expert. You might want to ask your doctor if they're consulted with anyone else. Or take your medical records to another doctor and get a second opinion.