Here are the facts on depression, conditions that have similar symptoms, and how to know the difference.
Depression: The Basics
Depression is a common mental health condition that affects how you feel, think, and act. You may feel sadness and lose interest in activities you normally enjoy. You may have emotional and physical issues that make it hard to function at home and at work.
Symptoms can include:
- Appetite changes
- Feelings of guilt or worthlessness
- Feelings of sadness or a depressed mood
- Loss of interest in activities
- Low energy
- Thoughts of suicide or death
- Trouble sleeping
- Trouble thinking, focusing, or making decisions
- Weight loss or gain
Talk to your doctor if you have these symptoms. If they last 2 weeks or more and limit your ability to function, you may have depression.
Conditions That May Look Like Depression
Here are common mental health and medical conditions that look like depression and how they differ.
Anemia is when you don’t have enough healthy red blood cells to carry oxygen to your organs. You may have symptoms like fatigue and weakness, which are also symptoms of depression. And if you don’t treat anemia, it may lead to complications including depression.
There’s a link between depression and anxiety. Anxiety is sometimes a symptom of depression. Anxiety may also trigger depression. Many people have both depression and anxiety.
They’re different conditions, but they have some overlapping symptoms, like nervousness, irritability, problems sleeping, and a hard time concentrating. Your doctor can tell you if you have anxiety, depression, or both.
Attention deficit hyperactivity disorder (ADHD)
If you have ADHD and you’re depressed, you may move, think, and talk more slowly. The stress of living with ADHD may lead to feelings of depression. This is called situational depression, which means it’s happening because of the ADHD challenges. If you treat your ADHD, your depression symptoms may improve.
When you have bipolar disorder, you alternate between periods of depression and mania, or elevated mood. During a depressed period, you may feel sadness, hopelessness, and loss of interest in activities. But then it will switch to a period of mania, when you feel euphoric, energetic, or irritable. Those are not symptoms of clinical depression.
Chronic fatigue syndrome (CFS)
Fatigue, which is a common symptom of depression, is also the main symptom of chronic fatigue syndrome. CFS may also interfere with your ability to do things you normally do. It could also lead to problems with memory, concentration, and sleep. Your doctor or counselor can help you figure out if your symptoms are related to depression or chronic fatigue syndrome.
This mental health condition is similar to bipolar disorder, but milder. You may have mood swings and changes in energy that resemble bipolar disorder and depression. But cyclothymia has highs and quick mood changes that aren’t common in depression.
It’s not fully understood, but there’s a link between depression and diabetes. It’s possible the stress of living with diabetes causes depression. It’s also possible diabetes leads to other health problems that worsen depression symptoms.
Weakness, fatigue, and weight loss are symptoms of both. If you have diabetes, you may also have increased thirst, blurred vision, numbness in your hands or feet, slow-healing sores, frequent urination, infections, or dry mouth. Those are not symptoms of depression.
Many people who have fibromyalgia, a condition that causes chronic muscle pain and fatigue, also have depression. Chemical imbalances in your brain that cause mood changes also may be linked to fibromyalgia. The constant pain and ongoing fatigue may also lead to depression.
If you have fibromyalgia, you may also have other symptoms that don’t resemble depression, like increased sensitivity to pain, muscle stiffness or spasms, a deep ache or burning pain, and numbness and tingling in your hands, arms, and legs.
Lethargy, a low mood, memory loss, and irritability are common symptoms of depression. They are also signs of hypercalcemia, or high levels of calcium in your blood.
Hypercalcemia is caused by many different things, including diseases, medications, and dehydration. If you have these symptoms, your doctor can order a blood test to see if you have hypercalcemia.
Hypothyroidism is often misdiagnosed as depression. If your thyroid is underactive, it may affect your emotions. You may have symptoms of depression, like fatigue, insomnia, and brain fog. Many people with hypothyroidism are prescribed antidepressants, mood stabilizers, and sedatives, when it’s their thyroid that needs to be treated instead.
Posttraumatic stress disorder (PTSD)
Emotional struggles, sleep problems, concentration issues, irritation, and anger are symptoms of both depression and PTSD. But PTSD happens after you’ve had a traumatic event. Symptoms can start soon after the event or even years later.
If your symptoms seem related to an event, and if you have strong memories, flashbacks, or nightmares about it, it may be PTSD.
Premenstrual dysphoric disorder (PMDD)
With PMDD, you may have symptoms similar to depression, like a depressed mood, irritability, and sadness. It may interfere with your social and work life. But PMDD is tied to your menstrual cycle and may be an extension of premenstrual syndrome, or PMS.
Vitamin D deficiency
Vitamin D helps your body function well. Signs that you aren’t getting enough vitamin D include weakness, pain, fatigue, and mood changes. Even though they’re caused by a vitamin D deficiency, they may be mistaken for depression. Your doctor can give you a blood test to measure your levels of vitamin D to see if that’s causing your symptoms.