Depression, known as major depressive disorder (MDD), is a common medical illness that negatively impacts the way you think, feel, and act. This may lead to emotional and physical problems that can interfere with your ability to function at home and work.
Dysthymia, known as persistent depressive disorder (PDD), is a chronic form of depression that’s less severe than MDD, but lasts for years. It can significantly impact your:
- family life
- social life
- physical health
- daily activities
PDD is used to describe a person who experiences clinically significant depression over a long period of time. The level of depression is usually not severe enough to meet the criteria for MDD.
Thus, one of the biggest differences between the two conditions is their relationship to time:
- People with MDD have a normal mood baseline when they’re not experiencing depression.
- People with PDD experience depression all the time and don’t remember — or know — what it feels like not to be depressed.
Time is also a consideration in diagnosing the two conditions:
- For a diagnosis of MDD, symptoms must last at least two weeks.
- For a diagnosis of PDD, symptoms must have been present for at least two years.
The symptoms of MDD and PDD are basically the same, sometimes differing in intensity. They include:
- feeling sad, empty, tearful or hopeless
- responding to even small matters with anger or frustration
- losing interest in normal daily activities such as sports, sex, or hobbies
- sleeping too little or too much
- responding to even small tasks with a lack of energy
- losing appetite or increasing food cravings
- losing or gaining weight
- feeling guilty or worthless
- having trouble making decisions, thinking, concentrating and remembering
To oversimplify, the symptoms of PDD might be less intense or debilitating, but they’re continuous and long-lasting.
Treatment for any type of depression is typically customized for the individual. Treatment for MDD and PDD usually includes a combination of psychotherapy and medication.
For either condition, your doctor might recommend antidepressants, such as:
- selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine (Prozac) and sertraline (Zoloft)
- serotonin-norepinephrine reuptake inhibitors (SNRIs), such as desvenlafaxine (Pristiq, Khedezla) and levomilnacipran (Fetzima)
- tricyclic antidepressants (TCAs), such as imipramine (Tofranil)
For therapy, your doctor might recommend:
- cognitive behavioral therapy
- behavioral activation
Even though PDD and MDD are separate conditions, people can have them both at the same time. If you’ve had PDD for a number of years and then have a major depressive episode, this is referred to as double depression.
Whether you’re experiencing PDD, MDD, or another type of depression, these are all real and serious conditions. There is help available. With a proper diagnosis and treatment plan, the majority of people with depression overcome it.
If you recognize the symptoms of depression in your mood, behavior, and outlook, talk about it with your doctor or a psychiatrist.