Although depression is a mental illness, it can also cause physical symptoms. Pain, stomach upset, fatigue, and restlessness are just a few potential physical effects of depression. People can have these physical symptoms for a variety of reasons, but they may not realize depression can be among the potential causes.  Physical symptoms of depression can include:

PainStomach issuesWeakened immunitySleep difficultiesFatigueChanges in activity levelsHigh blood pressureAppetite and weight changes

Certain treatments used for depression, such as medication, can also have physical side effects like nausea, weight changes, and sexual dysfunction. If you have physical symptoms of depression, your doctor and mental health care provider can help you better understand and manage them. 

Pain

People with depression may have vague aches and pains that affect their joints, limbs, or back. Some people have “all over” body pain which may be chronic and debilitating. A few explanations have been proposed:

Neurotransmitter dysregulation: One theory is that both can be caused by a dysregulation of neurotransmitters such as serotonin. Some people with depression and pain may feel better if they take an antidepressant that influences the reuptake of serotonin and norepinephrine in the brain. Differences in pain perception: Another theory is that people with depression may feel pain differently. A 2015 study of pain processing found that people diagnosed with major depression had a lower pain threshold and tolerance compared to people who were not depressed.

A 2017 study found that one of the most common forms of pain in adults, lower back pain, could be directly linked to depression. An earlier study found that people with depression are 60% more likely to have back pain than those who aren’t depressed.

Gastrointestinal Symptoms

People with depression may have frequent stomach problems, such as nausea, bloating, diarrhea, or constipation.  One possible explanation for these symptoms involves a neurotransmitter in the brain and gut called serotonin. The brain chemical is linked to depression because it is believed to help regulate mood, but researchers also know that it also plays a role in maintaining digestive function.  Researchers are very interested in the “gut-brain” connection, which they hope could reveal how mental and digestive health influence one another. In addition to serotonin, microbes found in the gut are being explored as potential contributors to everything from mood to immunity—both of which have implications for depression. 

Immunity

Stress can also make a person’s immune system work less optimally, making them more likely to get sick. When someone with a weakened immune system gets sick, it may take longer to get better. Some infections, like the common cold, are generally not serious. However, a weak immune system puts a person at risk of developing complications from an infection or contracting an infection that is harder to treat.  The relationship between immune function and depression is still being researched. Some studies have hypothesized that chronic stress may cause an inflammatory response that can change how mood-regulating chemicals in the brain work.

Sleep Problems

When doctors and mental health professionals are considering a diagnosis of depression, sleep disorders are among the “core” symptoms they look for.  The relationship between depression and sleep goes both ways, as having trouble sleeping for any reason (such as a medical condition like sleep apnea) increases a person’s risk for depression.  Some research has suggested that disturbances in circadian rhythm (which can interrupt sleep) may contribute to depression. Understanding and even learning how to alter the sleep-wake cycle is one avenue researchers are exploring as they search for new ways to treat depression. 

Fatigue

People who are depressed often feel that no matter how much they sleep, they never feel rested. They may have a hard time getting out of bed in the morning or struggle to perform activities of daily living, such as bathing or doing household chores.  Fatigue is not only one of the most common physical effects of depression but tends to be one of the more challenging to treat. Even after starting an antidepressant, fatigue persists in many people with major depression. Depression and fatigue may become part of a cycle where ongoing low energy and decreased motivation worsen depression. Therefore, adequately addressing fatigue is crucial in creating an effective treatment plan for someone diagnosed with depression. 

Psychomotor Symptoms

The term “psychomotor” refers to symptoms that make a person feel as though they are thinking and/or moving at a different pace than usual. For example, some people with depression perceive their thoughts as sluggish and feel like their movements seem heavy. Others experience symptoms at the opposite end of the spectrum. They may say that they “can’t sit still,” or feel fidgety, restless, and agitated. Mentally, they may experience anxious or even intrusive thoughts. For this reason, doctors and mental health professionals need to also consider the possibility that psychomotor changes may be a sign of depression rather than just a part of aging.

High Blood Pressure

People who are depressed may be under stress often or for an extended period. While it’s not the only cause, chronic stress has been known to contribute to high blood pressure (hypertension). Chronic stress, in particular, has been linked to elevated blood pressure. In turn, hypertension increases a person’s risk of cardiovascular disease, which includes heart attacks and strokes.

Appetite and Weight Changes

Depression in and of itself can make someone feel like eating more or less than they typically do. People who are depressed may report they have lost weight without trying or gained weight without being sure of why. 

Emotional Eating

One factor that may contribute to weight gain is “emotional eating” which refers to a person using food to self-medicate feelings of depression. These behaviors can lead to weight gain over time. If someone is overweight or obese, changes in self-image, associated health problems, and weight stigma can also contribute to (or worsen) depression.  For example, a 2019 study proposed a specific link between higher amounts of body fat mass and depression (as the researchers did not find a link between depression and non-fat body mass).

Weight Loss

Depression can also cause someone to lose weight. Factors that may cause weight loss in someone who is depressed include:

Loss of appetiteLow energyLow motivation that affects the desire to prepare mealsBowel symptoms 

People who have eating disorders, such as anorexia nervosa, often also have depression or another mental illness. Weight loss in eating disorders can be extreme and cause various physical symptoms. Several studies have suggested that malnutrition from inadequate food intake may worsen depression, though additional research is needed to support the theory. People who do not get enough eat for other reasons, such as those living in poverty, patients with cancer, and the elderly, are also at risk for depression related to malnutrition.

Medication Side Effects

Both prescription and over-the-counter (OTC) medications can come with side effects. While they are usually mild and get better as the body adjusts to the drug, others may be severe and persistent. Medications used to treat depression may have side effects, many of which are physical. A few examples of common side effects of antidepressants include:

Appetite changes, weight gain/loss Blurred vision Difficulty focusing or concentrating Dizziness Dry mouth Fatigue Insomnia Nausea Sexual dysfunction (trouble maintaining an erection, pain with intercourse, inability to orgasm)

If medication side effects are too difficult to cope with, a person is less likely to continue taking it. For someone who takes medication to manage depression, side effects from antidepressants can be a barrier to treatment. The mental and emotional side effects of antidepressants can be serious and may indicate a medication is not the right treatment for you. If you experience worsening feelings of anxiety and depression and/or thoughts of suicide after starting an antidepressant, seek immediate medical care.

Coping With Physical Symptoms of Depression

When you go to your doctor with a physical complaint, they may not initially ask you about emotional symptoms. However, they won’t be able to accurately diagnose depression without it. Before you can begin to deal with the physical effects of depression, you need an accurate diagnosis. For more mental health resources, see our National Helpline Database. Your doctor also needs this information to help them decide on the most effective way to treat depression, so it’s important you let them know about the emotional, mental, and physical symptoms you are having. 

A Word From Verywell

Depression hurts but mentally and physically. While the physical symptoms of depression often get less attention than the emotional ones, it is essential to pay attention to how you feel. Recognizing that feelings of physical pain, frequent sickness, sleep problems, fatigue, and changes in activity, appetite, and weight might be linked to depression can improve your chances of getting an accurate diagnosis. Treatment for depression often involves medication, psychotherapy, and lifestyle changes. By treating your symptoms, you can begin feeling better and find relief from some of the physical effects of depression.