6 Conditions That Look Like Major Depressive Disorder

Some health conditions can mimic the symptoms of major depressive disorder. Some medications can also cause similar symptoms as a side effect.

Healthcare providers often screen for these conditions while diagnosing depression, or if treatment for depression isn’t working the way it should, says Aimee Daramus, PsyD, a licensed clinical psychologist and author of “Understanding Bipolar Disorder.”

This article explains what major depressive disorder looks like, and explores other conditions that look like major depressive disorder. It also explores medications and their possible contributions to major depression.

What Is Major Depressive Disorder?

While most people feel sad once in a while, major depressive disorder is different. Also known as depression or clinical depression, it is a mood disorder that can make you feel sad or low for weeks or months at a time.

Depression is caused by multiple factors including an imbalance of certain brain chemicals, known as neurotransmitters, that affect mood.

The symptoms include:

• Persistent feelings of sadness or emptiness
• Feelings of worthlessness or hopelessness
• Feelings of guilt or anxiety
• Feelings of irritability or frustration
• Loss of interest in activities and interests
• Lack of energy and fatigue
• Difficulty with cognitive tasks like paying attention, recalling things, or making decisions
• Sleep changes, such as sleeping a lot or being unable to sleep
• Changes in appetite and weight
• Unexplained aches and pains such as headaches, body aches, cramps, or digestives issues
• Thoughts of death or suicide

Major depressive disorder is typically diagnosed and treated by mental healthcare providers. Treatment may involve therapy, antidepressant medications, or in some cases, neurotherapeutics.

6 Conditions That Look Like Major Depressive Disorder

Below, Dr. Daramus explains how these conditions may resemble major depressive disorder and how they can be identified and treated.

Low Vitamin D Levels

Vitamin D is a nutrient that contributes to the functioning of the immune, nervous, and muscular systems. It also plays an important role in maintaining bone health by helping the body absorb calcium.

Approximately 5% of people in the United States have vitamin D deficiency. Low vitamin D levels may cause symptoms similar to major depressive disorder.

According to Dr. Daramus, the symptoms may include:

• Low mood
• Hopelessness
• Fatigue
• Loss of appetite 
• Changes in weight
• Sleep difficulties
• Bone pain
• Muscle cramps or aches
• Weakness

Hypothyroidism

Hypothyroidism, also known as underactive thyroid, is a health condition caused when the thyroid gland doesn’t produce enough thyroid hormone. This hormone plays an important role in regulating metabolism. Low levels of thyroid hormone can cause your metabolism to slow down.

Hypothyroidism can also significantly affect emotions and cognitions, causing it to resemble depression. According to Dr. Daramus, the symptoms of hypothyroidism include:

• Depression
• Fatigue
• Weight gain
• Forgetfulness
• Brain fog
• Numbness or tingling in the hands
• Constipation
• Slower heart rate
• Muscle soreness or weakness
• Inability to tolerate cold temperatures
• Dry and coarse hair and skin
• Higher cholesterol levels
• Irregular or heavy menstruation or fertility issues 

Hormonal Imbalances

In addition to thyroid hormones, adrenal problems can affect your levels of cortisol, a stress hormone, says Dr. Daramus. Known as adrenal insufficiency, it can occur when the adrenal gland doesn’t produce enough cortisol. Cortisol plays an important role in regulating your blood sugar, blood pressure, and metabolism.

According to Dr. Daramus, the symptoms of adrenal insufficiency can include:

• Depression
• Irritability
• Difficulty thinking and planning
• Chronic fatigue
• Loss of appetite
• Weight gain
• Nausea or vomiting
• Diarrhea or abdominal pain
• Low blood pressure
• Low blood sugar
• Muscle weakness
• Joint pain

Stimulant Withdrawal

Stimulants are substances that cause a burst of energy and alertness. However, strong stimulants carry a risk of depression as part of withdrawal, says Dr. Daramus. Stimulants include cocaine, meth, and caffeine, as well as certain medications like Ritalin and Adderall.

Misdiagnosis of depression and bipolar disorder are common in people who use cocaine, but any addictive stimulant, including prescription medication, can result in brief periods of depression during withdrawal, according to Dr. Daramus.

Symptoms of withdrawal can include:

• Depression
• Irritability
• Agitation or restlessness
• Fatigue
• Slowness
• General discomfort or unease
• Increased appetite
• Nightmares
• Cravings for the substance
• Suicidal thoughts
  

Use of Birth Control Pills

Oral contraceptives, or birth control pills, contain hormones that help prevent pregnancy. However, they can cause some side effects, particularly in the first few months of taking them. The side effects can include:

• Spotting or irregular menstrual bleeding
• Nausea or dizziness
• Breast tenderness
• Blood clots, particularly in people who smoke or are above 35 
• Depression or mood changes

While the research has been conflicted on this, Dr. Daramus says a study of over a million people in Denmark reported that there is a small but real risk of depression from taking birth control pills. "This study confirmed the perceptions of many people who had noticed the onset of depression happening around the time they went on birth control."

The risk of developing depression may be higher in people who have a history of depression.

Use of Heart Medications

The research about the link between medications for heart disease and depression has also been conflicting. Some studies show that they do not cause depression; whereas, other studies and reports from patients suggest that medications like statins, beta-blockers, and calcium-channel blockers can cause depression, says Dr. Daramus.

There are multiple possible explanations for the conflicting data, according to Dr. Daramus. She says one possibility is that certain populations are more prone to this side effect.

Dr. Daramus notes that another possibility is that the medication may not be causing the depression, but that it is an understandable emotional reaction to developing heart problems and needing treatment. "Therefore, the depression might coincide with beginning the medication, making it appear that the medication caused it directly."

Depression in the context of a heart condition can cause symptoms such as:

• Mood and attitude changes
• Fear and uncertainty about the future
• Lack of confidence in one’s abilities
• Guilt over unhealthy habits that may have contributed to heart disease
• Lack of energy
• Difficulty sleeping

A Word From Verywell

The mind and body are deeply intertwined, so mental health conditions like major depressive disorder can cause both physical and emotional symptoms. Similarly, physical health conditions and certain medications can cause emotional symptoms like depression as well.

This can sometimes make it hard to determine the cause of the symptoms you’re experiencing. However, it’s important to correctly identify the condition, so it can be treated. Otherwise, treatment may not be effective and the symptoms may persist.