Double depression is when two specific types of depression overlap. It’s a serious condition that can become life threatening if not treated.

In medical terms, it’s the coexistence of persistent depressive disorder (PDD) and major depressive disorder (MDD).

We explore the similarities and differences between PDD and MDD, and what happens when they occur together.

Double depression is when you have PDD and develop MDD.

These two types of depression have many symptoms in common. In general, MDD is a severe form of depression while PDD is a lower-grade, chronic depression.

The Diagnostic and Statistical Manual of Mental Disorders (DSM) is the handbook that healthcare professionals use to diagnose mental health disorders. The current version, DSM-5, includes criteria for diagnoses of PDD and MDD.

While researchers and others call it double depression, the DSM-5 does not list it as an official diagnosis.

If you have “double depression,” your doctor will diagnose coexisting PDD and MDD, but you can still call it double depression.

Persistent depressive disorder

PDD is a fairly new diagnosis. It used to be called dysthymia or chronic major depression.

This is the criteria for diagnosing PDD:

  • adults: depressed mood for at least 2 years
  • children and teens: depressed or irritated mood for at least 1 year
  • symptoms have not let up for more than 2 months at a time

In addition, you must have at least two of these symptoms:

  • poor appetite or eating too much
  • insomnia or sleeping too much
  • fatigue or low energy
  • low self-esteem
  • poor concentration and decision making
  • sense of hopelessness

Because PDD is a long-term condition, it may not be apparent to you right now that it’s possible to feel any other way. You might even chalk it up to your personality — but it’s not you. It’s not your fault. It’s the disorder, and it is treatable.

Coexisting disorders are common and may include:

Major depressive disorder

MDD is a mood disorder that brings intense, persistent feelings of sadness and a general loss of interest. It has a profound effect on how you feel and behave. It may be difficult, if not impossible, to carry on as usual.

Criteria for diagnosis include at least five of the symptoms listed below, occurring within a 2-week period. One of these must be loss of interest, loss of pleasure, or depressed mood.

  • depressed mood (or irritability in children and teens)
  • diminished interest or loss of pleasure in most things
  • changes in appetite or weight
  • insomnia or oversleeping
  • altered or slowed body movements
  • lack of energy and fatigue
  • sense of worthlessness or guilt
  • slowed thinking, or difficulty concentrating and making decisions
  • recurring thoughts of death or suicide, having a plan for suicide, or attempting suicide

To qualify for a diagnosis of MDD, these symptoms must not be able to be explained by the effects of any substance or another medical condition.

It’s not uncommon for someone who had a major depressive episode to have another within their lifetime.

Major depression is a serious disorder, but it can be treated.

PDD is chronic. It doesn’t usually involve clear-cut episodes of depression. Symptoms of major depression are powerful. When they hit, you’ll likely recognize them as being outside your normal baseline.

If that has happened to you, you’re not alone. Most people with PDD have at least one episode of major depression in their lifetime.

Symptoms of double depression vary from person to person. Your PDD symptoms may increase in intensity, especially depressed mood and feelings of hopelessness. Getting through your normal routine with PDD, already difficult, may become even more of a challenge.

You might also have:

  • severe emptiness, guilt, or worthlessness
  • unexplained physical aches and pains or a general feeling of illness
  • slowed body movements
  • thoughts of self-harm
  • recurring thoughts of death or suicide
  • planning for suicide

These are signs that you should seek immediate treatment.

what to do if you’re having or suspect someone else is having suicidal thoughts or PLANS

If you, or someone you know, is having thoughts of self-harm:

  • contact your doctor right away or go to the emergency room
  • call 911 or the free, confidential 24/7 National Suicide Prevention Lifeline at 1-800-273-8255
  • stay with the person until the crisis resolves

If you have symptoms of depression, see your primary care physician or mental health provider as soon as possible.

Your visit may include a physical examination and lab tests to rule out some medical conditions with similar symptoms. There’s no specific lab test to diagnose PDD, MDD, or double depression.

If you already have a diagnosis of PDD, your doctor may recognize the signs of major depression fairly quickly.

Your primary care doctor may make the diagnosis or refer you to a mental health professional for evaluation. The diagnosis involves answering a series of questions designed to see if you meet diagnostic criteria for PDD, MDD, or both. It’s important to be completely open about all your symptoms.

If you do fit the criteria for both conditions, you have double depression.

Treatment for PDD and MDD are similar. This usually involves medication, psychotherapy, or a combination of the two. It’s not the same for everybody, though. Your doctor must tailor treatment to your specific needs.

Some medications for depression are:

It’s important that you take these medications exactly as prescribed. It also requires a bit of patience. If you don’t feel the effects right away, don’t give up. It can take a few weeks for these drugs to start working.

It can also take some trial and error to find the correct medication and dosage. Your doctor will make adjustments as needed until you start to feel better.

If you think your medication isn’t working or are experiencing unpleasant side effects, it’s important to discuss this with your doctor.

Don’t stop taking the medication abruptly unless advised by your prescribing physician to do so, as it can lead to withdrawal symptoms or worsening depression. Your doctor may prescribe an alternative drug or help you taper off safely.

In addition to drug therapy, you may benefit from psychotherapy. This can include talk therapy and cognitive behavioral therapy (CBT). You can do this one-on-one with your therapist or in a group setting.

In the event that you can’t take care of yourself or are at risk of harming yourself, you may need to stay in a hospital until the danger passes.

When severe depression doesn’t respond to these therapies, others include:

  • Electroconvulsive therapy (ECT): This is a procedure in which electric currents are used to stimulate the brain into having a seizure. It causes changes to brain chemistry that can relieve depression.
  • Transcranial magnetic stimulation (TMS): This involves use of magnetic pulses to stimulate nerve cells in the brain that are associated with mood regulation and depression.

Your doctor may make diet, exercise, and other lifestyle recommendations to complement your treatment.

You might also find some benefit in joining a support group for people living with depression. Ask your doctor for a referral to local resources.

The causes of depression aren’t always clear. Rather than a single cause, it could be a combination of factors such as:

  • brain changes
  • brain chemistry
  • environment
  • genetics
  • hormones

Things that may increase your risk of depression include:

  • low self-esteem
  • traumatic events such as abuse, loss of a loved one, and financial or relationship difficulties
  • family members who have a history of depression, alcohol use disorder, and suicide
  • other mental disorders such as post-traumatic stress disorder (PTSD), anxiety, or eating disorders
  • drugs and alcohol
  • serious chronic illness

Double depression is when someone with persistent depressive disorder develops major depression. Researchers don’t know exactly what causes double depression, but help is available.

Both PDD and MDD can be treated and effectively managed.

Take the first step. See your doctor as soon as possible so you can get on the road to recovery and start enjoying a better quality of life.