Medically reviewed by Susan Vachon, PA-C on January 10, 2022
If you’ve been feeling sad, down, and unmotivated for several weeks or longer, it’s possible you’re suffering from depression. Use this guide to learn more about depression, including signs and symptoms, how to get diagnosed, and possible treatments.
Depression is not a simple disease. Rather, it’s a complex illness that can affect the ways you think, feel, and act. Researchers are still working to understand all the mechanisms of depression, but they do have a solid base of knowledge already.
What is depression?
Depression, also known as major depressive disorder or clinical depression, is a mood disorder that makes you feel sad and disinterested in the world around you. Unlike typical sadness, which may come and go, depression lasts for at least two weeks (and often persists much longer) and includes a whole host of additional symptoms.
Scientists think that depression happens when there’s an imbalance of neurotransmitters in the brain. Neurotransmitters are chemicals that help to deliver messages between neurons. Neurons are also messengers, but in a different way. They’re responsible for sending signals to the rest of the brain and the nervous system, helping to control your thoughts and movements.
It’s a complicated system, so even a small imbalance in neurotransmitter levels can throw things off when neurons communicate with the brain and body. In depression, the brain may have too much or too little of three main neurotransmitters:
- Dopamine, which is responsible for rewarding you for positive behaviors as well as controlling movement.
- Norepinephrine, which is responsible for your attention levels, wakefulness, and stress and anxiety levels.
- Serotonin, which is responsible for your ability to sleep, feel hungry, and mood and pain levels.
When these neurotransmitters are unbalanced, it leads to changes in certain parts of the brain, including the amygdala, thalamus, and hippocampus. These areas of the brain are responsible for emotions, sensory information, and emotional memories, respectively, so this is what leads to many of the symptoms of depression.
How common is depression?
Depression is more common than you may realize. The World Health Organization estimates that 5% of adults suffer from depression globally, for a total of about 280 million people.
In the United States, about 6.7% of adults suffer from depression. That’s one in every 15 people, so there’s a good chance someone you know is struggling with this disorder.
What are the types of depression?
Major depressive disorder is the type of depression we generally think about when we use the word “depression.” However, there are many other types of depression out there with specific symptoms and causes. Some of them include:
- Persistent depressive disorder – When your depression lasts for more than two years.
- Bipolar disorder – Also known as manic depression, this disorder is characterized by people experiencing periods of extreme high energy and mania, followed by extreme depressive and low moods.
- Seasonal affective disorder (SAD) – With SAD, people typically become depressed in late fall and early winter, but their mood changes subside in the spring and summer.
- Premenstrual dysphoric disorder (PMDD) – About a week before a woman is on her period, she may experience PMDD, which is a more severe form of the more common premenstrual disorder (PMS).
- Postpartum depression – This happens in pregnant women after giving birth to their child.
- Psychotic depression – In addition to having severe depressive symptoms, people with this condition also have delusions or hallucinations.
General signs and symptoms
Just feeling sad doesn’t mean you have depression. There’s a lot more that goes into it than that. Let’s take a look at the signs and symptoms of depression.
What causes depression?
Unfortunately, doctors aren’t always sure what causes depression in a majority of cases. That said, the causes of depression can usually be attributed to one of four things:
- Having another serious medical condition. Having another medical condition, like cancer or heart disease, can be a factor in the development of depression. In fact, research shows that these may be the cause of 10% to 15% of depression cases in the United States.
- Having a family member with depression. While scientists haven’t narrowed down a gene linked to depression, they have noticed that depression tends to run in families. If a person has a parent or sibling with depression, they are two to three times more likely to develop depression than someone with no family history of depression.
- Chronic stress or trauma. In many cases, suffering through a traumatic event or having too much stress can trigger depression.
- Hormonal imbalances. Hormonal imbalances can play a big role in depression, especially in new mothers and people going through menopause. If you have an imbalance in your thyroid hormones, this can also lead to depressive symptoms.
What are the symptoms of depression?
The symptoms of depression can range from mild to severe. While you may not have all of these symptoms, you’ll likely have at least a few if you are suffering from depression:
- Feeling sad, empty, or hopeless
- Getting angry, frustrated, or irritable over the smallest of things
- No longer having interest in your favorite hobbies or activities
- Problems with sleep, including sleeping too much or too little
- Having low energy levels or feeling tired all the time
- Not feeling hungry (and losing weight) or feeling hungrier (and gaining weight)
- Feeling anxious, agitated, or restless
- Both moving and thinking slower than usual
- Feeling worthless or guilty about your past
- Placing blame on yourself for past failures
- Problems thinking and concentrating, as well as remembering things
- Having trouble making decisions
- Thinking suicidal or self-harm thoughts
- Having other physical problems without an explanation, like headaches or back pain
Keep in mind, just experiencing these symptoms once in a while does not mean you have depression. With depression, you’ll feel this way most of the time for an extended period.
Only a medical professional can definitively diagnose you with depression. That’s why, if you’re suffering from some of the above symptoms, your best bet is to speak with a doctor or other medical professional.
How is depression syndrome diagnosed?
Your doctor will use a few different tools to diagnose you with depression. First, they’ll probably ask you about the symptoms you’ve been experiencing. This may take the form of a psychiatric evaluation, where you fill out a questionnaire about your feelings, thoughts, behaviors, and other symptoms.
The symptoms we listed above are actually from the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), which is the go-to book of knowledge for mental health professionals. According to this manual, if you have five or more of those symptoms during a two-week period (with one being either depressed mood or loss of interest), you very likely have major depressive disorder.
Your doctor will also take into account any major life changes that have happened to you recently, like the loss of a loved one or major financial challenges. In many cases, depressive symptoms are normal after these types of events, so they don’t necessarily mean you have depression.
After confirming your symptoms, your doctor will then perform a few additional tests to see if there are any obvious causes for your depression. For example, a physical exam can help them see if you have another health issue that could be contributing to your depression. And lab tests can check your blood to see if your thyroid hormones are normal.
The risk factors for depression vary, as it can strike anyone at any time in their life. That said, it is more common in people in their teens, 20s, and 30s — though many older adults suffer as well. Women are also slightly more likely to have depression, but this could be because women are more likely to seek treatment for their symptoms.
With that said, there are some things that make it more likely you’ll experience depression. These risk factors include:
- Having low self-esteem, being overly self-critical, or being too dependent on others
- Experiencing a traumatic event, like the loss of a loved one, assault, or even relationship troubles
- Being a member of the LGBTQA+ community and not having a good support system
- Having any other mental health disorder, including PTSD, eating disorders, or anxiety disorders
- Having a long-term medical issue like heart disease, cancer, or strokes
- Taking some medications that have depression as a side effect, like high blood pressure medications or sleeping pills
- Using alcohol or drugs
- Having a family history of depression
Treatment and Therapies
Getting depression treatment can greatly improve your quality of life and help you feel happier and more stable. At this time, doctors rely on three main treatments for depression: medications, psychotherapies, and alternative therapies.
There are a number of medications your doctor might prescribe you depending on your symptoms. These typically work by altering the production of neurotransmitters in your brain. However, because there’s no single neurotransmitter typically responsible for depression, you may have to go through some trial and error to find the medication and dosage that’s appropriate for you.
- Selective serotonin reuptake inhibitors (SSRIs). This is the drug many doctors start with. It helps to increase levels of serotonin in your brain by blocking your neurons from reabsorbing it. This keeps more serotonin in the brain, hopefully helping neurons communicate with each other better. Common SSRIs include citalopram, escitalopram, fluoxetine, paroxetine, and sertraline.
- Serotonin-norepinephrine reuptake inhibitors (SNRIs). Like SSRIs, SNRIs block the reabsorption of serotonin, but they go a step further by also blocking reabsorption of norepinephrine. Some common ones include desvenlafaxine, duloxetine levomilnacipran, and venlafaxine.
- Tricyclic antidepressants. These days, these medications aren’t used as much because they have a lot of side effects. While they block the reabsorption of serotonin and norepinephrine, they also have effects on other neurotransmitters, leading to a lot of uncomfortable side effects. Common medications include nortriptyline, amitriptyline, doxepin, protriptyline, and trimipramine. However, sometimes they are needed and a medical professional is necessary to provide the safety monitoring and collaboration necessary to properly dispense this class of medications.
Luckily, many people find that psychotherapy is a great way to control their depression symptoms. Therapy can come in a lot of different forms. You may see a therapist one-on-one (individual therapy) or with others who have the same problems as you (group therapy). If you’re dealing with relationship issues, you may even have couples or family therapy. Types of psychotherapy you might try include:
- Psychodynamic therapy, which helps you resolve unconscious internal conflicts you’ve had throughout your life.
- Interpersonal therapy, which helps you work through your communication skills and increase your self-esteem.
- Cognitive behavioral therapy, which helps you establish new ways of thinking so you can change your behaviors.
There are a few additional, though less scientifically studied, ways of treating depression. These include:
- Acupuncture, which is a traditional Chinese medicine that is meant to redirect energy flow throughout the body.
- Hypnotherapy, which puts you in a trance to help you change the way you perceive the world and store your memories.
- Biofeedback, which monitors your breathing, heart rate, muscle activity, and more and makes recommendations on how to create physiologic changes.
While medication and therapy are two very effective ways of treating depression, there are additional things you can practice to help yourself start feeling better.
Changing the way you live your life can offer much-needed relief from your depressive symptoms. In particular, changing your diet can have big effects. Eating a Mediterranean diet has been shown to decrease depressive symptoms, as has eating more vegetables and legumes on a regular basis.
Exercise is also key in feeling better. Studies have shown that aerobic exercise, resistance exercise, and mixed exercise can all help with depression. When you exercise three to four times a week for 10 or more weeks, you can improve your depression symptoms.
Avoid alcohol and substance use
Because alcohol and substances can make depressive symptoms worse, it’s best to cut them out of your routine. Staying sober helps you take control of your mood and keeps you more stable as you work on healing your mind.
Learn how to set limits
Sometimes, you may have people in your life that trigger your symptoms. That’s why it’s important to know how to set limits. If you know someone is hurting your progress, even unintentionally, place limits on how often you interact with them. Give yourself permission and time to focus on yourself, and always stay self-aware of your progress.
This blog provides information about telemedicine, health and related subjects. The blog content and any linked materials herein are not intended to be, and should not be construed as a substitute for, medical or healthcare advice, diagnosis or treatment. Any reader or person with a medical concern should consult with an appropriately-licensed physician or other healthcare provider. This blog is provided purely for informational purposes.